Comprehensive Physiology Wiley Online Library

Neurophysiology of Breathing in Mammals

Full Article on Wiley Online Library



Abstract

The sections in this article are:

1 Respiratory Homeostasis and Control of Respiratory Movements
1.1 Effectors of Ventilation
1.2 Respiratory Muscles and Their Innervation
1.3 Summary
2 Central Location of Respiratory Controller
2.1 Historical Background
2.2 Summary
2.3 Modern View
2.4 Brain Stem Anatomy
2.5 Classification of Respiratory Neurons
2.6 Connections Between Respiratory Neurons
2.7 Location and Mechanisms for Generation of Respiratory Patterns
2.8 Production of Respiratory Pattern
2.9 Central Pattern Generation and Respiration
2.10 Hypothesis for Role of Dorsal and Ventral Respiratory Groups in Generating Respiratory Pattern
3 Sensors
3.1 Time Course of Responses to Respiratory Afferent Stimulation
3.2 Integrated Responses to Changes in Carbon Dioxide
3.3 Integrated Responses to Changes in Oxygen
3.4 Summary
4 Mechanoreceptors
4.1 Pulmonary Stretch Receptors
4.2 Summary
5 Exercise—An Example of an Integrated Response
5.1 Critique
6 State Dependence
7 Conclusion
Figure 1. Figure 1.

Schematic drawing for neural control of ventilation. Output of brain respiratory controller activates spinal and cranial motoneurons innervating thoracoabdominal and laryngeal‐pharyngeal muscles. Thoracoabdominal muscles control configuration of rib cage and diaphragm, which via mechanical coupling of lung (broken line) results in ventilation. Ease with which air enters and leaves the lungs is determined by airway caliber, partly controlled by laryngeal‐pharyngeal muscles, and via autonomic innervation of airway smooth muscle. Ventilation, along with nonventilatory factors, determines blood and brain fluid levels of O2, CO2, and pH. Levels of these regulated variables are transduced into a pattern of afferent activity at peripheral and intracranial chemoreceptors. These signals feed into respiratory controller, which makes appropriate adjustments in its output to motoneurons, thereby controlling ventilation and regulating , pH, and related variables. Respiratory controller makes adjustments in movements based on signals from mechanoreceptors in respiratory muscles and in lung and airways. , partial pressure of O2 in arterial blood.

Figure 2. Figure 2.

Neurophysiological investigation of central respiratory pattern generation seeks to explain timing and pattern of respiratory motor nerve outflow (e.g., traces 2–6) in terms of membrane, synaptic, and network properties of neurons with respiratory‐modulated discharge patterns [top trace, extracellular activity of an inspiratory‐modulated neuron in dorsal respiratory group (DRG)] and signals provided by respiratory‐related afferents, such as pulmonary mechanoreceptors. Traces from anesthetized, vagotomized adult cat. R, right; L, left; Phr, phrenic nerve; IC, intercostal nerve; T3, T7, T10: 3rd, 7th, and 10th thoracic root.

Figure 3. Figure 3.

Ramón y Cajal's model for respiratory control. Arrows indicate direction of nerve impulses. Respiratory neurons in solitary tract process information from vagal pulmonary afferents (K) [cell bodies in nodose ganglion (J)] and some blood factor present in local capillaries (A). Descending control signals go to spinal motoneurons (D) innervating intercostal muscles (F) or diaphragm (E, G).

From Ramón y Cajal
Figure 4. Figure 4.

A: ventral view; location in cat brain stem of ventral medullary regions possibly involved in central chemoreception. B‐E: dorsal view; dorsal (DRG), ventral (VRG), and pontine (PRG) respiratory groups, major clusters of respiratory related neurons. A, cranial nerves as indicated; C1, first cervical spinal root. Ventral surface is highly vascularized and only major blood vessels are indicated. Three areas are indicated where cooling, stimulation, and/or coagulation lead to reproducible alterations in respiratory outflow (see INTRACRANIAL CARBON DIOXIDE RECEPTION …, p. 492). B: cerebellum removed (normal position indicated by dotted lines, cerebellar peduncles indicated by flat surface just medial to V, VII, and VIII nerve roots). Populations of neurons are major concentrations of extracellularly recordable respiratory‐modulated neurons. Ventrolateral column, in regions of nucleus ambiguus and nucleus retroambigualis from C1 to retrofacial nucleus, is referred to as VRG. Population of predominantly expiratory neurons is most caudal (caudal VRG). Population of predominantly inspiratory neurons is between obex and retrofacial nucleus (rostral VRG). Another population of expiratory neurons is most rostral, just medial to retrofacial nucleus; this is referred to as the Bötzinger Complex (BötC). Dorsomedial population, spanning ∼2.0 mm rostral from obex, is in region of ventrolateral nucleus of solitary tract; it is referred to as DRG and contains predominantly inspiratory neurons. In dorsolateral rostral pons, in region of parabrachial nuclei and Kölliker‐Fuse nucleus, is another concentration of neurons seen most clearly in vagotomized preparations. It consists of a lateral inspiratory population and a medial expiratory population bridged by a phase‐spanning inspiratory‐expiratory (IE) population. This region is the PRG. C‐E: transverse sections of brain stem at levels indicated in B (see ref. for detailed anatomical descriptions). Location and extent of populations are only approximate and can vary in different preparations. A, nucleus ambiguus; AP, area postrema; BC, brachium conjunctivum; BP, brachium pontis; DMV, dorsal motor nucleus of vagus; KF, Kölliker‐Fuse nucleus; mV, motor trigeminal nucleus; NPBL, nucleus parabrachialis lateralis; NPBM, nucleus parabrachialis medialis; S, solitary tract; SV, spinal trigeminal nucleus; VH, ventral horn.

Figure 5. Figure 5.

Cycle‐triggered histograms of impulse discharge patterns of respiratory‐modulated brain stem neurons in decerebrate, barbiturate‐, or chloralose‐urethan‐anesthetized cats. Ordinate marker, 50 impulses/s. Onsets and offsets of discharge are smeared due to temporal dispersion of individual cycle lengths. Onsets and offsets of discharges of many I and E neurons overlap each other.

Figure 6. Figure 6.

Effect of multiple microlesions in VRG and DRG on integrated phrenic (Phr) nerve discharge in vagotomized anesthetized cat. Traces are clustered in pairs and each pair represents integrated phrenic nerve activity before and after lesion in area specified. A: left phrenic nerve discharge; B: right phrenic nerve discharge; C: locations of lesions, reconstructed from histological sections. Lesions were not made in rostral portions of left VRG because no respiratory‐modulated activity was found at sites indicated by Xs. Microlesions were made by passing current between 2 microelectrodes positioned ∼1 mm apart in same population. All lesions were completed in <10 h. Note that predominant effect of these lesions is to reduce amplitude of Phr nerve activity, with only modest effect on timing.

From Speck and Feldman
Figure 7. Figure 7.

Inspiratory cycle‐triggered histograms of phrenic nerve activity representing control cycles with no stimulation (thin line) and cycles with spinal cord stimulation at the C2 level, with optimal placement for stimulating descending axons of inspiratory premotor neurons (400‐ms train, 50 Hz, 100 μA; thick line) at 2 different delays. Stimulation elicits very short latency excitation due to orthodromic excitation followed by brief period of reduced activity. Transient depression of phrenic nerve activity has no lasting influence on subsequent evolution of phrenic discharge. Bins are 20 ms.

From Feldman et al.
Figure 8. Figure 8.

Generation of rhythmic movements can be considered to result from interaction among 4 components. Many different rhythmic patterns of motoneuronal activity, as indicated in neurograms at bottom, underlie resulting coordinated movement.

From Feldman and Grillner
Figure 9. Figure 9.

Examples of experimental perturbations that have marked effects on pattern of augmenting phrenic activity with modest change in timing. A: alteration of end‐expiratory percent CO2 in vagotomized and paralyzed cats; B: successive microlesions of DRG and VRG in vagotomized cat (see Fig. ).

Figure 10. Figure 10.

Two different schematic models for respiratory pattern generation. A: threshold model showing reciprocal relationship between amplitude of outflow and phase timing. B: timer model where amplitude of outflow and timing are separately determined; ⊝, possible pacemaker involvement in function generation.

From Feldman
Figure 11. Figure 11.

Cross‐correlation histogram and neuron → contralateral phrenic nerve correlations of an inspiratory augmenting neuron (I↗) and an inspiratory decrementing neuron (I), which were recorded simultaneously from separate microelectrodes in the VRG. A: cross‐correlogram of these 2 neurons exhibits a peak straddling zero lag. Underlying interaction responsible for this peak may be either mutual excitation or shared common input that may be excitatory or inhibitory. Means and SDs for indicated ranges of lag are shown on right. B: cross correlations between each of 2 neurons and contralateral phrenic and ipsilateral recurrent laryngeal nerve activities. Nerve activities were full‐wave rectified before processing. Mean and SD for each correlation is shown on left. Note peaks in neuron‐phrenic nerve correlations that suggest a projection from these neurons to phrenic motoneurons but not to recurrent laryngeal motoneurons. Recordings were obtained in paralyzed, nonvagotomized cat ventilated with cycle‐triggered pump. Bins are 0.2 ms.

From Feldman and Speck
Figure 12. Figure 12.

Reciprocal inhibition demonstrated by intracellular recording of membrane potentials and current injection (A, B) or Cl injection (C). A: phrenic motoneuron (top trace) and whole phrenic nerve (bottom trace) activities before (A1) and after (A2) hyperpolarizing current injection. B: internal intercostal motoneuron (top trace) and diaphragmatic EMG (bottom trace) before (B1) and after (B2) hyperpolarizing current injection. C: DRG inspiratory neuron (MPRB) and phrenic motoneuronal activity (PN) before and during Cl injection. EMG, electromyogram.

A from Berger ; B from Sears ; C from Richter et al.
Figure 13. Figure 13.

Effects on respiratory motor activity of stimulus trains (ST) delivered to vagus or superior laryngeal nerve. All traces are average of 21 respiratory cycles. Top trace represents control phrenic nerve activity. In middle trace, vagus nerve stimulation begins 100 ms after inspiratory onset and continues until inspiratory termination. In bottom trace, superior laryngeal nerve stimulation begins 100 ms after inspiratory onset and continues for 100 ms.

From Iscoe, Feldman, and Cohen
Figure 14. Figure 14.

Magnitude of perturbations necessary to produce inspiratory → expiratory phase transitions declines with time during inspiration. In all curves, ordinates represent magnitude of lung inflation (A‐C) or stimulating voltage (D, E); abscissas represent inspiratory duration [TI]. A: in spontaneously breathing anesthetized cats rebreathing from a small balloon, inspiratory duration decreases as CO2 necessarily increases. B: in paralyzed anesthetized or decerebrate cats, lung volume [produced by artificial inflation at higher (▴) or lower (▪) pressures] necessary to terminate inspiration is higher for shorter inspirations. C: after lesioning in PRG (▪), volume threshold for inspiratory phase termination greatly increases but still shows a time‐dependent decline (▴, prelesion control). D: in anesthetized cats, increased voltages of PRG stimulation are needed for earlier termination of inspiration. The voltage threshold is less when lungs are inflated (•) than when lungs are deflated (•). E: in decerebrate cats, higher current stimulation of intercostal nerve afferents is needed to terminate inspiration earlier. Increasing CO2 raises the threshold.

A from Clark and Euler ; B and C from Feldman and Gautier ; D from Euler and Trippenbach ; E from Speck and Webber
Figure 15. Figure 15.

Effects on peak integrated phrenic nerve activity of cooling the intermediate area of the ventral medulla. A: ventral surface temperatures at different levels; B: levels at different ventral surface temperatures. Data in A and B from vagotomized cat on constant artificial ventilation.

From Cherniack et al.
Figure 16. Figure 16.

A: mean values of carotid body‐chemoreceptor discharge in response to changes in at 3 levels of CO2. B: ventilatory response to hypoxia in 2 human subjects, 1 with low response (•), 1 with high response (•). Ventilation is plotted against alveolar . This is traditional hyperbolic response curve

A from Vidruk and Dempsey ; B from Rebuck and Slutsky
Figure 17. Figure 17.

Changes in tidal volume or peak phrenic activity with carotid sinus nerve stimuli given at various times during inspiration. Composite results of all cats studied, arranged in bins for each 5% of inspiration. All stimuli were 0.5 s in duration at 20–25 Hz. To normalize data obtained in different cats, the change from mean of unstimulated breaths has been used.

From Eldridge
Figure 18. Figure 18.

A‐C: effects of changes in pulmonary afferent and PRG activity on integrated phrenic nerve activity in 3 anesthetized paralyzed cats ventilated with a cycle‐triggered pump. Bars indicate inflation (A1, A2, B, C1 and C2) or vagal electrical stimulation (A3). A1: intact cat, no inflation during 4th and 9th cycle; A2: after bivagotomy; and A3: stimulation of afferent vagi. Stimulation lasted for duration of inspiration and was stopped for 4th and 9th cycles. Time scale: 1 s/small division. B: cat after bilateral lesions of PRG. When pump was stopped, there was apneustic inspiration that ceased spontaneously. C1: cat after bilateral lesions of PRG. Apneusis stopped only after inflation that commenced 10 s after onset of inspiration. Note that inspiratory cutoff produced by inflation was gradual. C2: inflation with smaller flow than C1. Note partial inhibition produced by 2 inflations during apneustic inspiration. Time scale: 1 s/small division.

From Feldman and Gautier
Figure 19. Figure 19.

Cycle‐triggered histograms of phrenic and recurrent laryngeal discharge in anesthetized paralyzed cat. Heavy lines indicate average discharge from 11 cycles with no lung inflation; light lines indicate cycles with lung inflation coincident with phrenic discharge. Note that lung inflation has no effect on evolution of phrenic discharge pattern but markedly inhibits laryngeal discharge.

From Feldman and Speck
Figure 20. Figure 20.

Types of inspiratory neuronal responses in impulse activity to withholding inflation in paralyzed anesthetized cats. Light lines, control; inflation delivered during inspiration. Heavy lines, test; inflation not delivered during inspiration. Each set of traces consists of cycle‐triggered histograms (50‐ms bins) of phrenic motoneuronal activity and neuronal impulse activity in equal numbers of control and test cycles. Number of cycles averaged: A, D, E, 20; B, 17; and C, 14. Types of neuronal responses: A, inflation (0), no change in slope of neuronal histogram; B, inflation (+), excited by inflation; C, inflation (0) recruited, no change of discharge (which stays at zero level) during time corresponding to control inspiratory duration, recruitment of firing during lengthened part of inspiration; D, inflation (−), inhibited by inflation; E, inflation (−) tonic, respiratory modulation inhibited by inflation, tonic discharge level.

From Cohen and Feldman
Figure 21. Figure 21.

Properties of hypothetical inhibitory process, ϕ, controlling expiratory duration, Te, as modified by stimulus inputs that shorten (left) or lengthen (right) duration of E. Phi is a function that decays exponentially (time constant = 1.5 s) from its maximum value of 1.0 at start of expiration. Control Te is 3.0 s; threshold for I onset (ϕTHR) is arbitrarily set at 0.135. Left top, vertical arrows represent pulse inputs that cause reduction in ϕ by 0.25, followed by a rebound increase of 0.125; left bottom, shortening of expiration produced by inputs at different times; right top, vertical arrows and lines represent pulse inputs that cause increase in ϕ of 0.250; right bottom, lengthening of Te produced by inputs at different times. Tec, control Te; Test, stimulus cycle Te.

From Cohen and Feldman
Figure 22. Figure 22.

Ventilatory response (Va) and arterial acid‐base status during steady‐state rhythmic exercise in healthy young adults. Abscissa indicates exercise intensity as a function of CO2 production (). Insert shows time course of ventilatory response.

From Dempsey et al.
Figure 23. Figure 23.

Polygraph traces of phrenic responses and responses of an I(−) tonic neuron located in PRG, preventing inflation in a paralyzed decerebrate cat for 1 test cycle. Phr, integrated phrenic discharge; unit spikes, standard pulses derived from neuronal impulses. Inflation was applied during inspiration except during 3rd cycle when inflation was withheld (see also Fig. E).

From Feldman et al.


Figure 1.

Schematic drawing for neural control of ventilation. Output of brain respiratory controller activates spinal and cranial motoneurons innervating thoracoabdominal and laryngeal‐pharyngeal muscles. Thoracoabdominal muscles control configuration of rib cage and diaphragm, which via mechanical coupling of lung (broken line) results in ventilation. Ease with which air enters and leaves the lungs is determined by airway caliber, partly controlled by laryngeal‐pharyngeal muscles, and via autonomic innervation of airway smooth muscle. Ventilation, along with nonventilatory factors, determines blood and brain fluid levels of O2, CO2, and pH. Levels of these regulated variables are transduced into a pattern of afferent activity at peripheral and intracranial chemoreceptors. These signals feed into respiratory controller, which makes appropriate adjustments in its output to motoneurons, thereby controlling ventilation and regulating , pH, and related variables. Respiratory controller makes adjustments in movements based on signals from mechanoreceptors in respiratory muscles and in lung and airways. , partial pressure of O2 in arterial blood.



Figure 2.

Neurophysiological investigation of central respiratory pattern generation seeks to explain timing and pattern of respiratory motor nerve outflow (e.g., traces 2–6) in terms of membrane, synaptic, and network properties of neurons with respiratory‐modulated discharge patterns [top trace, extracellular activity of an inspiratory‐modulated neuron in dorsal respiratory group (DRG)] and signals provided by respiratory‐related afferents, such as pulmonary mechanoreceptors. Traces from anesthetized, vagotomized adult cat. R, right; L, left; Phr, phrenic nerve; IC, intercostal nerve; T3, T7, T10: 3rd, 7th, and 10th thoracic root.



Figure 3.

Ramón y Cajal's model for respiratory control. Arrows indicate direction of nerve impulses. Respiratory neurons in solitary tract process information from vagal pulmonary afferents (K) [cell bodies in nodose ganglion (J)] and some blood factor present in local capillaries (A). Descending control signals go to spinal motoneurons (D) innervating intercostal muscles (F) or diaphragm (E, G).

From Ramón y Cajal


Figure 4.

A: ventral view; location in cat brain stem of ventral medullary regions possibly involved in central chemoreception. B‐E: dorsal view; dorsal (DRG), ventral (VRG), and pontine (PRG) respiratory groups, major clusters of respiratory related neurons. A, cranial nerves as indicated; C1, first cervical spinal root. Ventral surface is highly vascularized and only major blood vessels are indicated. Three areas are indicated where cooling, stimulation, and/or coagulation lead to reproducible alterations in respiratory outflow (see INTRACRANIAL CARBON DIOXIDE RECEPTION …, p. 492). B: cerebellum removed (normal position indicated by dotted lines, cerebellar peduncles indicated by flat surface just medial to V, VII, and VIII nerve roots). Populations of neurons are major concentrations of extracellularly recordable respiratory‐modulated neurons. Ventrolateral column, in regions of nucleus ambiguus and nucleus retroambigualis from C1 to retrofacial nucleus, is referred to as VRG. Population of predominantly expiratory neurons is most caudal (caudal VRG). Population of predominantly inspiratory neurons is between obex and retrofacial nucleus (rostral VRG). Another population of expiratory neurons is most rostral, just medial to retrofacial nucleus; this is referred to as the Bötzinger Complex (BötC). Dorsomedial population, spanning ∼2.0 mm rostral from obex, is in region of ventrolateral nucleus of solitary tract; it is referred to as DRG and contains predominantly inspiratory neurons. In dorsolateral rostral pons, in region of parabrachial nuclei and Kölliker‐Fuse nucleus, is another concentration of neurons seen most clearly in vagotomized preparations. It consists of a lateral inspiratory population and a medial expiratory population bridged by a phase‐spanning inspiratory‐expiratory (IE) population. This region is the PRG. C‐E: transverse sections of brain stem at levels indicated in B (see ref. for detailed anatomical descriptions). Location and extent of populations are only approximate and can vary in different preparations. A, nucleus ambiguus; AP, area postrema; BC, brachium conjunctivum; BP, brachium pontis; DMV, dorsal motor nucleus of vagus; KF, Kölliker‐Fuse nucleus; mV, motor trigeminal nucleus; NPBL, nucleus parabrachialis lateralis; NPBM, nucleus parabrachialis medialis; S, solitary tract; SV, spinal trigeminal nucleus; VH, ventral horn.



Figure 5.

Cycle‐triggered histograms of impulse discharge patterns of respiratory‐modulated brain stem neurons in decerebrate, barbiturate‐, or chloralose‐urethan‐anesthetized cats. Ordinate marker, 50 impulses/s. Onsets and offsets of discharge are smeared due to temporal dispersion of individual cycle lengths. Onsets and offsets of discharges of many I and E neurons overlap each other.



Figure 6.

Effect of multiple microlesions in VRG and DRG on integrated phrenic (Phr) nerve discharge in vagotomized anesthetized cat. Traces are clustered in pairs and each pair represents integrated phrenic nerve activity before and after lesion in area specified. A: left phrenic nerve discharge; B: right phrenic nerve discharge; C: locations of lesions, reconstructed from histological sections. Lesions were not made in rostral portions of left VRG because no respiratory‐modulated activity was found at sites indicated by Xs. Microlesions were made by passing current between 2 microelectrodes positioned ∼1 mm apart in same population. All lesions were completed in <10 h. Note that predominant effect of these lesions is to reduce amplitude of Phr nerve activity, with only modest effect on timing.

From Speck and Feldman


Figure 7.

Inspiratory cycle‐triggered histograms of phrenic nerve activity representing control cycles with no stimulation (thin line) and cycles with spinal cord stimulation at the C2 level, with optimal placement for stimulating descending axons of inspiratory premotor neurons (400‐ms train, 50 Hz, 100 μA; thick line) at 2 different delays. Stimulation elicits very short latency excitation due to orthodromic excitation followed by brief period of reduced activity. Transient depression of phrenic nerve activity has no lasting influence on subsequent evolution of phrenic discharge. Bins are 20 ms.

From Feldman et al.


Figure 8.

Generation of rhythmic movements can be considered to result from interaction among 4 components. Many different rhythmic patterns of motoneuronal activity, as indicated in neurograms at bottom, underlie resulting coordinated movement.

From Feldman and Grillner


Figure 9.

Examples of experimental perturbations that have marked effects on pattern of augmenting phrenic activity with modest change in timing. A: alteration of end‐expiratory percent CO2 in vagotomized and paralyzed cats; B: successive microlesions of DRG and VRG in vagotomized cat (see Fig. ).



Figure 10.

Two different schematic models for respiratory pattern generation. A: threshold model showing reciprocal relationship between amplitude of outflow and phase timing. B: timer model where amplitude of outflow and timing are separately determined; ⊝, possible pacemaker involvement in function generation.

From Feldman


Figure 11.

Cross‐correlation histogram and neuron → contralateral phrenic nerve correlations of an inspiratory augmenting neuron (I↗) and an inspiratory decrementing neuron (I), which were recorded simultaneously from separate microelectrodes in the VRG. A: cross‐correlogram of these 2 neurons exhibits a peak straddling zero lag. Underlying interaction responsible for this peak may be either mutual excitation or shared common input that may be excitatory or inhibitory. Means and SDs for indicated ranges of lag are shown on right. B: cross correlations between each of 2 neurons and contralateral phrenic and ipsilateral recurrent laryngeal nerve activities. Nerve activities were full‐wave rectified before processing. Mean and SD for each correlation is shown on left. Note peaks in neuron‐phrenic nerve correlations that suggest a projection from these neurons to phrenic motoneurons but not to recurrent laryngeal motoneurons. Recordings were obtained in paralyzed, nonvagotomized cat ventilated with cycle‐triggered pump. Bins are 0.2 ms.

From Feldman and Speck


Figure 12.

Reciprocal inhibition demonstrated by intracellular recording of membrane potentials and current injection (A, B) or Cl injection (C). A: phrenic motoneuron (top trace) and whole phrenic nerve (bottom trace) activities before (A1) and after (A2) hyperpolarizing current injection. B: internal intercostal motoneuron (top trace) and diaphragmatic EMG (bottom trace) before (B1) and after (B2) hyperpolarizing current injection. C: DRG inspiratory neuron (MPRB) and phrenic motoneuronal activity (PN) before and during Cl injection. EMG, electromyogram.

A from Berger ; B from Sears ; C from Richter et al.


Figure 13.

Effects on respiratory motor activity of stimulus trains (ST) delivered to vagus or superior laryngeal nerve. All traces are average of 21 respiratory cycles. Top trace represents control phrenic nerve activity. In middle trace, vagus nerve stimulation begins 100 ms after inspiratory onset and continues until inspiratory termination. In bottom trace, superior laryngeal nerve stimulation begins 100 ms after inspiratory onset and continues for 100 ms.

From Iscoe, Feldman, and Cohen


Figure 14.

Magnitude of perturbations necessary to produce inspiratory → expiratory phase transitions declines with time during inspiration. In all curves, ordinates represent magnitude of lung inflation (A‐C) or stimulating voltage (D, E); abscissas represent inspiratory duration [TI]. A: in spontaneously breathing anesthetized cats rebreathing from a small balloon, inspiratory duration decreases as CO2 necessarily increases. B: in paralyzed anesthetized or decerebrate cats, lung volume [produced by artificial inflation at higher (▴) or lower (▪) pressures] necessary to terminate inspiration is higher for shorter inspirations. C: after lesioning in PRG (▪), volume threshold for inspiratory phase termination greatly increases but still shows a time‐dependent decline (▴, prelesion control). D: in anesthetized cats, increased voltages of PRG stimulation are needed for earlier termination of inspiration. The voltage threshold is less when lungs are inflated (•) than when lungs are deflated (•). E: in decerebrate cats, higher current stimulation of intercostal nerve afferents is needed to terminate inspiration earlier. Increasing CO2 raises the threshold.

A from Clark and Euler ; B and C from Feldman and Gautier ; D from Euler and Trippenbach ; E from Speck and Webber


Figure 15.

Effects on peak integrated phrenic nerve activity of cooling the intermediate area of the ventral medulla. A: ventral surface temperatures at different levels; B: levels at different ventral surface temperatures. Data in A and B from vagotomized cat on constant artificial ventilation.

From Cherniack et al.


Figure 16.

A: mean values of carotid body‐chemoreceptor discharge in response to changes in at 3 levels of CO2. B: ventilatory response to hypoxia in 2 human subjects, 1 with low response (•), 1 with high response (•). Ventilation is plotted against alveolar . This is traditional hyperbolic response curve

A from Vidruk and Dempsey ; B from Rebuck and Slutsky


Figure 17.

Changes in tidal volume or peak phrenic activity with carotid sinus nerve stimuli given at various times during inspiration. Composite results of all cats studied, arranged in bins for each 5% of inspiration. All stimuli were 0.5 s in duration at 20–25 Hz. To normalize data obtained in different cats, the change from mean of unstimulated breaths has been used.

From Eldridge


Figure 18.

A‐C: effects of changes in pulmonary afferent and PRG activity on integrated phrenic nerve activity in 3 anesthetized paralyzed cats ventilated with a cycle‐triggered pump. Bars indicate inflation (A1, A2, B, C1 and C2) or vagal electrical stimulation (A3). A1: intact cat, no inflation during 4th and 9th cycle; A2: after bivagotomy; and A3: stimulation of afferent vagi. Stimulation lasted for duration of inspiration and was stopped for 4th and 9th cycles. Time scale: 1 s/small division. B: cat after bilateral lesions of PRG. When pump was stopped, there was apneustic inspiration that ceased spontaneously. C1: cat after bilateral lesions of PRG. Apneusis stopped only after inflation that commenced 10 s after onset of inspiration. Note that inspiratory cutoff produced by inflation was gradual. C2: inflation with smaller flow than C1. Note partial inhibition produced by 2 inflations during apneustic inspiration. Time scale: 1 s/small division.

From Feldman and Gautier


Figure 19.

Cycle‐triggered histograms of phrenic and recurrent laryngeal discharge in anesthetized paralyzed cat. Heavy lines indicate average discharge from 11 cycles with no lung inflation; light lines indicate cycles with lung inflation coincident with phrenic discharge. Note that lung inflation has no effect on evolution of phrenic discharge pattern but markedly inhibits laryngeal discharge.

From Feldman and Speck


Figure 20.

Types of inspiratory neuronal responses in impulse activity to withholding inflation in paralyzed anesthetized cats. Light lines, control; inflation delivered during inspiration. Heavy lines, test; inflation not delivered during inspiration. Each set of traces consists of cycle‐triggered histograms (50‐ms bins) of phrenic motoneuronal activity and neuronal impulse activity in equal numbers of control and test cycles. Number of cycles averaged: A, D, E, 20; B, 17; and C, 14. Types of neuronal responses: A, inflation (0), no change in slope of neuronal histogram; B, inflation (+), excited by inflation; C, inflation (0) recruited, no change of discharge (which stays at zero level) during time corresponding to control inspiratory duration, recruitment of firing during lengthened part of inspiration; D, inflation (−), inhibited by inflation; E, inflation (−) tonic, respiratory modulation inhibited by inflation, tonic discharge level.

From Cohen and Feldman


Figure 21.

Properties of hypothetical inhibitory process, ϕ, controlling expiratory duration, Te, as modified by stimulus inputs that shorten (left) or lengthen (right) duration of E. Phi is a function that decays exponentially (time constant = 1.5 s) from its maximum value of 1.0 at start of expiration. Control Te is 3.0 s; threshold for I onset (ϕTHR) is arbitrarily set at 0.135. Left top, vertical arrows represent pulse inputs that cause reduction in ϕ by 0.25, followed by a rebound increase of 0.125; left bottom, shortening of expiration produced by inputs at different times; right top, vertical arrows and lines represent pulse inputs that cause increase in ϕ of 0.250; right bottom, lengthening of Te produced by inputs at different times. Tec, control Te; Test, stimulus cycle Te.

From Cohen and Feldman


Figure 22.

Ventilatory response (Va) and arterial acid‐base status during steady‐state rhythmic exercise in healthy young adults. Abscissa indicates exercise intensity as a function of CO2 production (). Insert shows time course of ventilatory response.

From Dempsey et al.


Figure 23.

Polygraph traces of phrenic responses and responses of an I(−) tonic neuron located in PRG, preventing inflation in a paralyzed decerebrate cat for 1 test cycle. Phr, integrated phrenic discharge; unit spikes, standard pulses derived from neuronal impulses. Inflation was applied during inspiration except during 3rd cycle when inflation was withheld (see also Fig. E).

From Feldman et al.
References
 1. Achard, O., and V. M. Bucher. Courants d'action bulbaires à rythme respiratoire. Helv. Physiol. Pharmacol. Acta 12: 265–283, 1954.
 2. Acker, H., and R. G. O'Regan. The effects of stimulation of autonomic nerves on carotid body blood flow in the cat. J. Physiol. London 315: 99–110, 1981.
 3. Adrian, E. D. Afferent impulses in the vagus and their effect on respiration. J. Physiol. London 79: 332–358, 1933.
 4. Adrian, E. D., and F. J. J. Buytendijk. Potential changes in the isolated brainstem of goldfish. J. Physiol. London 71: 121–135, 1931.
 5. Ahmad, H. R., and H. H. Loeschcke. Transient and steady state responses of pulmonary ventilation to the medullarly extracellular pH after approximately rectangular changes in alveolar PCO2. Pfluegers Arch. 395: 285–292, 1982.
 6. Ahmad, H. R., and H. H. Loeschcke. Fast bicarbonatechloride exchange between brain cells and brain extracellular fluid in respiratory acidosis. Pfluegers Arch. 395: 293–299, 1982.
 7. Ahmad, H. R., and H. H. Loeschcke. Fast bicarbonatechloride exchange between plasma and brain extracellular fluid at maintained PCO2. Pfluegers Arch. 395: 300–305, 1982.
 8. Allen, W. F. Experimental anatomical studies on the visceral bulbospinal pathway in the cat and the guinea pig. J. Comp. Neurol. 42: 393–456, 1926.
 9. Amendt, K., J. Czachurski, K. Dembowsky, and, H. Seller. Bulbospinal projections to the intermediolateral cell column, a neuroanatomical study. J. Auton. Nerv. Syst. 1: 103–117, 1979.
 10. Aminoff, M. J., and T. A. Sears. Spinal integration of segmental, cortical and breathing inputs to thoracic respiratory motoneurones. J. Physiol. London 215: 557–575, 1971.
 11. Andersen, P., and T. A. Sears. Medullary activation of intercostal fusimotor and alpha motoneurones. J. Physiol. London 209: 739–755, 1970.
 12. Andrezik, J. A., V. Chan‐Palay, and S. L. Palay. The nucleus paragigantocellularis lateralis in the rat. Conformation and cytology. Anat. Embryol. 161: 355–371, 1981.
 13. Andrezik, J. A., V. Chan‐Palay, and S. L. Palay. The nucleus paragigantocellularis lateralis in the rat. Demonstration of afferents by retrograde transport of horseradish peroxidase. Anat. Embryol. 161: 373–390, 1981.
 14. Anthonisen, N. R., and R. M. Cherniack. Ventilatory control in lung disease. In: Lung Biology in Health and Disease. Regulation of Breathing, edited by T. F. Hornbein. New York: Dekker, 1981, vol. 17, pt. 2, p. 965–987.
 15. Aoki, M., S. Mori, K. Kawahara, H. Watanabe, and N. Ebata. Generation of spontaneous respiratory rhythm in high spinal cats. Brain Res. 202: 51–63, 1980.
 16. Asanuma, H. Microstimulation technique. In: Electrophysiological Techniques, edited by D. R. Humphrey. Bethesda, MD: Soc. Neurosci., 1979, p. 67–77.
 17. Asmussen, E. Control of ventilation in exercise. Exercise Sport Sci. Rev. 11: 24–54, 1983.
 18. Asmussen, E., and M. Nielsen. Pulmonary ventilation and effect of oxygen breathing in heavy exercise. Acta Physiol. Scand. 43: 365–378, 1958.
 19. Astrand, P.‐O., and, K. Rodahl. Textbook of Work Physiology. New York: McGraw‐Hill, 1977.
 20. Averill, D. B., W. E. Cameron, and A. J. Berger. Monosynaptic connections of pulmonary stretch receptors with P cells. Soc. Neurosci. Abstr. 8: 558 1982.
 21. Averill, D. B., W. E. Cameron, and A. J. Berger. Monosynaptic excitation of dorsal medullary respiratory neurons by slowly adapting pulmonary stretch receptors. J. Neurophysiol. 52: 771–785, 1984.
 22. Backman, S. B., D. Ballantyne, S. W. Mifflin, C. Anders, D. Jordan, M. Spyer, and D. W. Richter. Evidence for a monosynaptic connection between slowly adapting pulmonary stretch receptor afferents and inspiratory beta neurones. Pfluegers Arch. 402: 129–136, 1984.
 23. Bainton, C. R., and P. A. Kirkwood. The effect of carbon dioxide on the tonic and the rhythmic discharges of expiratory bulbospinal neurones. J. Physiol. London 296: 291–314, 1979.
 24. Bainton, C. R., P. A. Kirkwood, and T. A. Sears. On the transmission of the stimulating effects of carbon dioxide to the muscles of respiration. J. Physiol. London 280: 249–272, 1978.
 25. Baker, J. P.Jr., and J. E. Remmers. Temporal correlation of graded reversible inspiratory inhibition with discharge patterns of late inspiratory neurons located in the dorsal respiratory group in cats. Brain Res. 200: 331–340, 1980.
 26. Baker, J. P., Jr., and J. E. Remmers. Response of medullary respiratory neurons to rostral pontine stimulation. Respir. Physiol. 50: 197–208, 1982.
 27. Baker, J. P., Jr., J. E. Remmers, and M. K. Younes. Graded inspiratory inhibition: specific effects of flow rate. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 46: 669–674, 1979.
 28. Baker, T. L., A. Netick, and W. C. Dement. Sleep‐related apneic and apneustic breathing following pneumotaxic lesion and vagotomy. Respir. Physiol. 46: 271–294, 1981.
 29. Ballantyne, D., S. Donoghue, D. Jordan, M. Meesmann, D. W. Richter, and K. M. Spyer. Respiratory influences on vagal afferent endings in the medulla: a study on baroreceptor and lung stretch neurones. J. Physiol. London 312: 28P–29P, 1980.
 30. Ballantyne, D., and D. W. Richter. The functional differences between post‐inspiratory and expiratory neurones. Pfluegers Arch. 394: R56, 1982.
 31. Ballantyne, D., and D. W. Richter. Post‐synaptic inhibition of bulbar inspiratory neurones in the cat. J. Physiol. London 348: 67–87, 1984.
 32. Band, D. M., I. R. Cameron, and S. J. G. Semple. Oscillations in arterial pH with breathing in the cat. J. Appl. Physiol. 26: 261–267, 1969.
 33. Band, D. M., C. B. Wolff, J. Ward, G. M. Cochrane, and, J. Prior. Respiratory oscillations in arterial carbon dioxide tension as a control signal in exercise. Nature London 283: 84–85, 1980.
 34. Barillot, J. C., and, M. Dussardier. Modalités de décharge des motoneurones laryngés inspiratoires dans diverses conditions expérimentales. J. Physiol. Paris 66: 593–629, 1973.
 35. Barillot, J. C., and, M. Dussardier. Activité des motoneurones laryngés expiratoires. J. Physiol. Paris 72: 311–343, 1976.
 36. Bartlett, D., Jr. Effects of vagal afferents on laryngeal responses to hypocapnia and hypoxia. Respir. Physiol. 42: 189–198, 1980.
 37. Bartlett, D.Jr., S. L. Knuth, and K. V. Knuth. Effects of pulmonary stretch receptor blockade on laryngeal responses to hypercapnia and hypoxia. Respir. Physiol. 45: 67–77, 1981.
 38. Bartlett, D.Jr., J. E. Remmers, and, H. Gautier. Laryngeal regulation of respiratory airflow. Respir. Physiol. 18: 194–204, 1973.
 39. Bartoli, A., B. A. Cross, A. Guz, A. Huszczuk, and, R. Jefferies. The effect of varying tidal volume on the associated phrenic motoneurone output: studies of vagal and chemical feedback. Respir. Physiol. 25: 135–155, 1975.
 40. Bassal, M., and A. L. Bianchi. Effets de la stimulation des structures nerveuses centrales sur les activités respiratoires efférentes chez le chat. I. Réponses à la stimulation corticale. J. Physiol. Paris 77: 741–757, 1981.
 41. Bassal, M., and A. L. Bianchi. Effets de la stimulation de structures nerveuses centrales sur les activités respiratoires efférentes chez le chat. II. Réponses à la stimulation souscorticale. J. Physiol. Paris 77: 759–777, 1981.
 42. Bassal, M., and A. L. Bianchi. Inspiratory onset or termination induced by electrical stimulation of the brain. Respir. Physiol. 50: 23–40, 1982.
 43. Bassal, M., A. L. Bianchi, and, M. Dussardier. Effets de la stimulation des structures nerveuses centrales sur l'activité des neurones respiratoires chez le chat. J. Physiol. Paris 77: 779–795, 1981.
 44. Batsel, H. L. Localization of bulbar respiratory center by microelectrode sounding. Exp. Neurol. 9: 410–426, 1964.
 45. Batsel, H. L. Some functional properties of bulbar respiratory units. Exp. Neurol. 11: 341–366, 1965.
 46. Baumgarten, R. von, and E. Kanzow. The interaction of two types of inspiratory neurons in the region of the tractus solitarius of the cat. Arch. Ital. Biol. 96: 361–373, 1958.
 47. Baumgarten, R. von, and S. Nakayama. Spontane und reizbedingte Anderungen der antidromen Erregbarkeit von bulbären respiratorischen Nervenzellen der Katze. Pfluegers Arch. 281: 245–258, 1964.
 48. Bennett, F. M., R. D. Tallman, Jr., and F. S. Grodins. Effects of small changes in PaO2 on the ventilatory response to CO2 infusion. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 55: 1426–1432, 1983.
 49. Berger, A. J. Dorsal respiratory group neurons in the medulla of cat: spinal projections, responses to lung inflation and superior laryngeal nerve stimulation. Brain Res. 135: 231–254, 1977.
 50. Berger, A. J. Phrenic motoneurons in the cat: subpopulations and nature of respiratory drive potentials. J. Neurophysiol. 42: 76–90, 1979.
 51. Berger, A. J. The distribution of the cat's carotid sinus nerve afferent and efferent cell bodies using the horseradish peroxidase technique. Brain Res. 190: 309–320, 1980.
 52. Berger, A. J. Properties of medullary respiratory neurons. Federation Proc. 40: 2378–2383, 1981.
 53. Berger, A. J., and D. B. Averill. Projection of single pulmonary stretch receptors to solitary tract region. J. Neurophysiol. 49: 819–830, 1983.
 54. Berger, A. J., D. B. Averill, and W. E. Cameron. Morphology of inspiratory neurons located in the ventrolateral nucleus of the tractus solitarius of the cat. J. Comp. Neurol. 224: 60–70, 1984.
 55. Berger, A. J., and K. A. Cooney. Ventilatory effects of kainic acid injection of the ventrolateral solitary nucleus. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 52: 131–140, 1982.
 56. Berger, A. J., J. G. Davies, and T. A. Sears. Time signatures of peripheral and central chemoreceptor drives to feline respiratory motoneurones. J. Physiol. London 334: 41P, 1983.
 57. Berger, A. J., D. A. Herbert, and R. A. Mitchell. Properties of apneusis produced by reversible cold block of the rostral pons. Respir. Physiol. 33: 323–337, 1978.
 58. Berger, A. J., and R. A. Mitchell. Evoked phrenic nerve responses to electrical stimulation of the ventral medulla in anesthetized cats (Abstract). Physiologist 17: 180 1974.
 59. Berger, A. J., and R. A. Mitchell. Lateralized phrenic nerve responses to stimulating respiratory afferents in the cat. Am. J. Physiol. 230: 1314–1320, 1976.
 60. Berger, A. J., R. A. Mitchell, and J. W. Severinghaus. Regulation of respiration. N. Engl. J. Med. 297: 92–97, 1977.
 61. Berger, A. J., R. A. Mitchell, and J. W. Severinghaus. Regulation of respiration. N. Engl. J. Med. 297: 138–143, 1977.
 62. Berger, A. J., R. A. Mitchell, and J. W. Severinghaus. Regulation of respiration. N. Engl. J. Med. 297: 194–201, 1977.
 63. Berman, A. L. The Brain Stem of the Cat. Madison: Univ. of Wisconsin Press, 1968.
 64. Berndt, J., W. Berger, and C. O. Trouth. Respiratory and circulatory effects of 100 meq/l potassium or 2 percent procaine in the cerebrospinal fluid of cats. Pfluegers Arch. 321: 346–363, 1970.
 65. Berssenbrugge, A., J. A. Dempsey, C. Iber, J. Skatrud, and, P. Wilson. Mechanism of hypoxia‐induced periodic breathing during sleep in humans. J. Physiol. London 343: 507–526, 1983.
 66. Bertrand, F., and, A. Hugelin. Respiratory synchronizing function of nucleus parabrachialis medialis: pneumotaxic mechanisms. J. Neurophysiol. 34: 189–207, 1971.
 67. Bertrand, F., A. Hugelin, and J. F. Vibert. Quantitative study of anatomical distribution of respiration related neurons in the pons. Exp. Brain. Res. 16: 383–399, 1973.
 68. Bertrand, F., A. Hugelin, and J. F. Vibert. A stereological model of pneumotaxic oscillator based on spatial and temporal distributions of neuronal bursts. J. Neurophysiol. 37: 91–107, 1974.
 69. Bianchi, A. L. Localisation et étude des neurones respiratoires bulbaires. Mise en jeu antidromique par stimulation spinale ou vagale. J. Physiol. Paris 63: 5–40, 1971.
 70. Bianchi, A. L. Modalitiés de décharge et propriétés anatomofonctionnelles des neurones respiratories bulbaires. J. Physiol. Paris 64: 555–587, 1974.
 71. Bianchi, A. L., and J. C. Barillot. Activity of medullary respiratory neurones during reflexes from the lungs in cats. Respir. Physiol. 25: 335–352, 1975.
 72. Bianchi, A. L., and J. C. Barillot. Effects of anesthesia on activity patterns of respiratory neurones. Adv. Exp. Med. Biol. 99: 17–22, 1978.
 73. Bianchi, A. L., and J. C. Barillot. Respiratory neurons in the region of the retrofacial nucleus: pontile, medullary, spinal and vagal projections. Neurosci. Lett. 31: 277–282, 1982.
 74. Bianchi, A. L., and, M. Denavit‐Saubié. Neurogenesis of Central Respiratory Rhythm: Electrophysiological, Pharmacological and Clinical Aspects, Lancaster, UK: MTP Press, 1985.
 75. Bianchi, A. L., and W. M. St. John. Pontile axonal projections of medullary respiratory neurons. Respir. Physiol. 45: 167–183, 1981.
 76. Bianchi, A. L., and W. M. St. John. Medullary axonal projections of respiratory neurons of pontile pneumotaxic center. Respir. Physiol. 48: 357–373, 1982.
 77. Binet, L., M. V. Strumza, and J. M. Strumza‐Poutonnet. Sur la “respiration” experimentalle medullaire. J. Physiol. Paris 45: 41–43, 1953.
 78. Biscoe, T. J., and, P. Willshaw. Stimulus‐response relationships of the peripheral arterial chemoreceptors. In: Lung Biology in Health and Disease. Regulation of Breathing, edited by T. F. Hornbein. New York: Dekker, 1981, vol. 17, pt. 1, p. 321–346.
 79. Black, A. M., and R. W. Torrance. Chemoreceptor effects in the respiratory cycle. J. Physiol. London 189: 59P–61P, 1967.
 80. Bledsoe, S. W., and T. F. Hornbein. Central chemosensors and the regulation of their chemical environment. In: Lung Biology in Health and Disease. Regulation of Breathing, edited by T. F. Hornbein. New York: Dekker, 1981, vol. 17, pt. 1, p. 347–428.
 81. Bouverot, P. Control of breathing in birds compared with mammals. Physiol. Rev. 58: 604–655, 1978.
 82. Bouverot, P., R. Flandrois, R. Puccinelli, and P. De Jours. Étude du rôle des chémorécepteurs artériels dans la régulation de la respiration pulmonaire chez le chien eveillé. Arch. Int. Pharmacodyn. Ther. 157: 253–271, 1965.
 83. Boyd, T. E., and D. A. Maaske. Vagal inhibition of inspiration, and accompanying changes of respiratory rhythm. J. Neurophysiol. 2: 533–542, 1939.
 84. Bradley, G. W. Control of the breathing pattern. In: Respiratory Physiology II, edited by J. G. Widdicombe. Baltimore, MD: University Park, 1977, vol. 14, p. 185–217. (Int. Rev. Physiol. Ser.)
 85. Bradley, G. W., C. von Euler, I. Marttila, and, B. Roos. Transient and steady state effects of CO2 on mechanisms determining rate and depth of breathing. Acta Physiol. Scand. 92: 341–350, 1974.
 86. Bradley, G. W., C. von Euler, I. Marttila, and, B. Roos. Steady state effects of CO2 and temperature on the relationship between lung volume and inspiratory duration (Hering‐Breuer threshold curve). Acta Physiol. Scand. 92: 351–363, 1974.
 87. Bradley, G. W., C. von Euler, I. Marttila, and, B. Roos. A model of the central and reflex inhibition of inspiration in the cat. Biol. Cybern. 19: 105–116, 1975.
 88. Bramble, D. M., and D. R. Carrier. Running and breathing in mammals. Science 219: 251–256, 1983.
 89. Breckenridge, C. G., and H. E. Hoff. Pontine and medullary regulation of respiration in the cat. Am. J. Physiol. 160: 385–394, 1950.
 90. Breuer, J. Self‐steering of respiration through the nervus vagus [English transl.]. In: Breathing: Hering‐Breuer Centenary Symposium, edited by R. Porter. London: Churchill, 1970, p. 365–394.
 91. Brodie, D. A., and H. L. Borison. Evidence for a medullary inspiratory pacemaker: functional concept of central regulation of respiration. Am. J. Physiol. 188: 347–354, 1957.
 92. Bronk, D. W., and L. K. Ferguson. The nervous control of intercostal respiration. Am. J. Physiol. 110: 700–707, 1935.
 93. Brookhart, J. M. The respiratory effects of localized faradic stimulation of the medulla oblongata. Am. J. Physiol. 129: 709–723, 1940.
 94. Brookhart, J. M. and V. B. Mountcastle (editors). Handbook of Physiology. The Nervous System. Motor Control. Bethesda, MD: Am. Physiol. Soc., 1981, sect. 1, vol. II, pt. 2.
 95. Brown, D. A., and P. R. Adams. Muscarinic suppression of a novel voltage‐sensitive K+ current in a vertebrate neurone. Nature London 283: 673–676, 1980.
 96. Brown, T. G. The intrinsic factors in the act of progression in the mammal. Proc. R. Soc. London Ser. B. 84: 308–319, 1911.
 97. Brown, T. G. On the nature of the fundamental activity of the nervous centres: together with an analysis of the conditioning of rhythmic activity in progression, and a theory of the evolution of function in the nervous system. J. Physiol. London 48: 18–46, 1914.
 98. Bruce, E. N., C. von Euler, J. R. Romaniuk, and S. M. Yamashiro. Bilateral reflex effects on phrenic nerve activity in response to single‐shock vagal stimulation. Acta Physiol. Scand. 116: 351–362, 1982.
 99. Bruce, E. N., C. von Euler, and S. M. Yamashiro. Reflex and central chemoceptive control of the time course of inspiratory activity. In: Central Nervous Control Mechanisms in Breathing, edited by C. von Euler and H. Lagercrantz. New York: Pergamon, 1979, p. 177–216.
 100. Bruce, E. N., and M. D. Goldman. High‐frequency oscillations in human respiratory electromyograms during voluntary breathing. Brain Res. 269: 259–265, 1983.
 101. Bruce, E. N., J. Mitra, and N. S. Cherniack. Central and peripheral chemoreceptor inputs to phrenic and hypoglossal motoneurons. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 53: 1504–1511, 1982.
 102. Bunn, J. C., and, J. Mead. Control of ventilation during speech. J. Appl. Physiol. 31: 870–872, 1971.
 103. Burke, R. O., and V. R. Edgerton. Motor unit properties and selective involvement in movement. In: Exercise and Sport Sciences Review, edited by J. H. Wilmore and J. F. Keogh. New York: Academic, 1975, p. 31–81.
 104. Burns, B. D., and G. C. Salmoiraghi. Repetitive firing of respiratory neurones during their burst activity. J. Neurophysiol. 23: 27–46, 1960.
 105. Byrne, J. H. Identification and initial characterization of a cluster of command and pattern‐generating neurons underlying respiratory pumping in Aplysia californica. J. Neurophysiol. 49: 491–508, 1983.
 106. Byrne, J. H., and, J. Koester. Respiratory pumping: neuronal control of a centrally commanded behavior in Aplysia. Brain Res. 143: 87–105, 1978.
 107. Bystrzycka, E. K. Afferent projections to the dorsal and ventral respiratory nuclei in the medulla oblongata of the cat studied by the horseradish peroxidase technique. Brain Res. 185: 59–66, 1980.
 108. Bystrzycka, E. K., and B. S. Nail. The source of respiratory drive to nasolabialis motoneurones in the rabbit; a HRP study. Brain Res. 266: 183–191, 1983.
 109. Caille, D., J. F. Vibert, F. Bertrand, H. Gromysz, and, A. Hugelin. Pentobarbitone effects on respiration related units; selective depression of bulbo‐pontine reticular neurones. Respir. Physiol. 36: 201–216, 1979.
 110. Caille, D., J. F. Vibert, and, A. Hugelin. Apneusis and apnea after parabrachial or Kölliker‐Fuse N. lesion; influence of wakefulness. Respir. Physiol. 45: 79–95, 1981.
 111. Camerer, H., D. W. Richter, N. Rohrig, and, M. Meesmann. Lung stretch receptor inputs to R beta‐neurones: a model for “respiratory gating.” In: Central Nervous Control Mechanisms in Breathing, edited by C. von Euler and H. Lagercrantz. New York: Pergamon, 1979, p. 261–266.
 112. Cameron, W. E., D. B. Averill, and A. J. Berger. Detailed morphology of cat phrenic motoneurons. In: Central Neural Production of Periodic Respiratory Movements, edited by J. L. Feldman and A. J. Berger. Evanston, IL: Northwestern Univ. Press, 1982, p. 124.
 113. Cameron, W. E., D. B. Averill, and A. J. Berger. Morphology of cat phrenic motoneurons as revealed by intracellular injection of horseradish peroxidase. J. Comp. Neurol. 219: 70–80, 1983.
 114. Carpenter, D. O., J. H. Hubbard, D. R. Humphrey, H. K. Thompson, and W. H. Marshall. Carbon dioxide effects on nerve cell function. In: Carbon Dioxide and pH Regulation of Cellular Functions, edited by G. Nahas and K. E. Schaefer. Heidelberg: Springer‐Verlag, 1974, p. 49–62.
 115. Carregal, E. J. A., B. Williams, and, L. Birzis. Respiratory centers in the dog and squirrel monkey: a comparative study. Respir. Physiol. 3: 333–348, 1967.
 116. Carruthers, B., J. Ponte, and M. J. Purves. Changes in partial pressure of carbon dioxide with time in carotid arterial blood in cats. J. Physiol. London 298: 13–23, 1980.
 117. Caverson, M. M., J. Ciriello, and F. R. Calaresu. Cardiovascular afferent inputs to neurons in the ventrolateral medulla projecting directly to the central autonomic area of the thoracic cord in the cat. Brain Res. 274: 354–358, 1983.
 118. Champagnat, J., M. Denavit‐Saubié, S. Moyanova, and, G. Rondounin. Involvement of amino acids in periodic inhibitions of bulbar respiratory neurons. Brain Res. 237: 351–365, 1982.
 119. Champagnat, J., M. Denavit‐Saubié, and G. R. Siggins. Rhythmic neuronal activities in the nucleus of the tractus solitarius isolated in vitro. Brain Res. 280: 155–159, 1983.
 120. Chapman, R. W., T. V. Santiago, and N. H. Edelman. Effects of graded reduction of brain blood flow on chemical control of breathing. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 47: 1289–1294, 1979.
 121. Cherniack, N. S., and M. D. Altose. Respiratory responses to ventilatory loading. In: Lung Biology in Health and Disease. Regulation of Breathing, edited by T. F. Hornbein. New York: Dekker, 1981, vol. 17, pt. 2, p. 905–964.
 122. Cherniack, N. S., N. H. Edelman, and, S. Lahiri. Hypoxia and hypercapnia as respiratory stimulants and depressants. Respir. Physiol. 11: 113–126, 1970.
 123. Cherniack, N. S., and C. von Euler. Central neural and reflex control of breathing. In: Assessment of Pulmonary Performance, edited by A. P. Fishman. New York: McGraw‐Hill, 1980, p. 69–75.
 124. Cherniack, N. S., C. von Euler, I. Homma, and F. F. Kao. Graded changes in central chemoceptor input by local temperature changes on the ventral surface of medulla. J. Physiol. London 287: 191–211, 1979.
 125. Cherniack, N. S., and A. P. Fishman. Abnormal breathing patterns. Med. Clin. North Am. 59: 1–45, 1975.
 126. Cherniack, N. S. and J. G. Widdicombe (editors). Handbook of Physiology. The Respiratory System. Control of Breathing. Bethesda, MD: Am. Physiol. Soc., 1986, sect. 3, vol. II.
 127. Christensen, E. H., R. Hedman, and, B. Saltin. Intermittent and continuous running. Acta Physiol. Scand. 50: 269–275, 1960.
 128. Christiansen, J., and J. S. Haldane. The influence of distension of the lungs on human respiration. J. Physiol. London 48: 272–277, 1914.
 129. Clark, F. J., and C. von Euler. On the regulation of depth and rate of breathing. J. Physiol. London 222: 267–295, 1972.
 130. Coglianese, C. J., C. N. Peiss, and R. D. Wurster. Rhythmic phrenic nerve activity and respiratory activity in spinal dogs. Respir. Physiol. 29: 247–254, 1977.
 131. Cohen, F. L. Effects of various lesions on crossed and uncrossed descending inspiratory pathways in the cervical spinal cord of the cat. J. Neurosurg. 39: 589–595, 1973.
 132. Cohen, M. I. Respiratory periodicity in the paralyzed, vagotomized cat: hypocapnic polypnea. Am. J. Physiol. 206: 845–854, 1964.
 133. Cohen, M. I. Discharge patterns of brain‐stem respiratory neurons in relation to carbon dioxide tension. J. Neurophysiol. 31: 142–165, 1968.
 134. Cohen, M. I. Discharge patterns of brain‐stem respiratory neurons during Hering‐Breuer reflex evoked by lung inflation. J. Neurophysiol. 32: 356–374, 1969.
 135. Cohen, M. I. Switching of the respiratory phases and evoked phrenic responses produced by rostral pontine electrical stimulation. J. Physiol. London 217: 133–158, 1971.
 136. Cohen, M. I. Synchronization of discharge, spontaneous and evoked, between inspiratory neurons. Acta Neurobiol. Exp. 33: 189–218, 1973.
 137. Cohen, M. I. Phrenic and recurrent laryngeal discharge patterns and the Hering‐Breuer reflex. Am. J. Physiol. 228: 1489–1496, 1975.
 138. Cohen, M. I. Synaptic relations between inspiratory neurons and the Hering‐Breuer reflex. In: Respiratory Centres and Afferent Systems, edited by B. Duron. Paris: INSERM, 1976, p. 19–29.
 139. Cohen, M. I. Neurogenesis of respiratory rhythm in the mammal. Physiol. Rev. 59: 1105–1173, 1979.
 140. Cohen, M. I. Central determinants of respiratory rhythm. Annu. Rev. Physiol. 43: 91–104, 1981.
 141. Cohen, M. I., and D. F. Donnelly. Excitation and inhibition of dorsal medullary inspiratory neurons by superior laryngeal afferent stimulation. Neurosci. Lett. Suppl. 10: S119–S120, 1982.
 142. Cohen, M. I., and J. L. Feldman. Models of respiratory phase‐switching. Federation Proc. 36: 2367–2374, 1977.
 143. Cohen, M. I., and J. L. Feldman. Central mechanisms controlling expiratory duration. Adv. Exp. Med. Biol. 99: 369–382, 1978.
 144. Cohen, M. I., and J. L. Feldman. Discharge properties of dorsal medullary inspiratory neurons: relation to pulmonary afferent and phrenic efferent discharge. J. Neurophysiol. 51: 753–776, 1984.
 145. Cohen, M. I., J. L. Feldman, and, D. Sommer. Caudal medullary expiratory neurone and external intercostal nerve discharge in the cat: effects of lung inflation. J. Physiol. London. 368: 147–178, 1985.
 146. Cohen, M. I., and, A. Hugelin. Suprapontine reticular control of intrinsic respiratory mechanisms. Arch. Ital. Biol. 103: 317–334, 1965.
 147. Cohen, M. I., M. F. Piercey, P. M. Gootman, and, P. Wolotsky. Synaptic connections between medullary inspiratory neurons and phrenic motoneurons as revealed by cross‐correlation. Brain Res. 81: 319–324, 1974.
 148. Cohen, M. I., and S. C. Wang. Respiratory neuronal activity in pons of cat. J. Neurophysiol. 22: 33–50, 1959.
 149. Colebatch, J. G., S. C. Gandevia, and D. I. McCloskey. Reduction in inspiratory activity in response to sternal vibration. Respir. Physiol. 29: 327–338, 1977.
 150. Coote, J. H. Respiratory and circulatory control during sleep. J. Exp. Biol. 100: 223–244, 1982.
 151. Corda, M., G. Eklund, and C. von Euler. External intercostal and phrenic alpha‐motor responses to changes in respiratory load. Acta Physiol. Scand. 63: 391–400, 1965.
 152. Cozine, R. A., and S. H. Ngai. Medullary surface chemoreceptors and regulation of respiration in the cat. J. Appl. Physiol. 22: 117–121, 1967.
 153. Cragg, P., L. Patterson, and M. J. Purves. The pH of brain extracellular fluid in the cat. J. Physiol. London 272: 137–166, 1977.
 154. Critchlow, V., and C. von Euler. Intercostal spindle activity and its gamma‐motor control. J. Physiol. London 168: 820–847, 1963.
 155. Cross, B. A., A. Davey, A. Guz, P. G. Katona, M. MacLean, K. Murphy, S. J. Semple, and, R. Stidwill. The role of spinal cord transmission in the ventilatory response to electrically induced exercise in the anesthetized dog. J. Physiol. London 329: 37–55, 1982.
 156. Cross, B. A., A. Davey, A. Guz, P. G. Katona, M. MacLean, K. Murphy, S. J. Semple, and, R. Stidwill. The pH oscillations in arterial blood during exercise; a potential signal for the ventilatory response in the dog. J. Physiol. London 329: 57–73, 1982.
 157. Cunningham, D. J. C., and W. N. Gardner. A quantitative description of the pattern of breathing during steady state CO2 inhalation in man, with special emphasis on expiration. J. Physiol. London 272: 613–632, 1977.
 158. Cunningham, D. J. C., M. G. Howson, and S. B. Pearson. The respiratory effects in man of altering the time profile of alveolar carbon dioxide and oxygen within each respiratory cycle. J. Physiol. London 234: 1–28, 1973.
 159. Dampney, R. A., A. K. Goodchild, L. G. Robertson, and, W. Montgomery. Role of ventrolateral medulla in vasomoter regulation: a correlative anatomical and physiological study. Brain Res. 249: 223–235, 1982.
 160. D'Angelo, E. Mechanisms controlling inspiration studied by electrical vagal stimulations in rabbits. Respir. Physiol. 38: 185–202, 1979.
 161. Davies, D. G., and C. D. Barnes. Regulation of Ventilation and Gas Exchange. New York: Academic, 1978.
 162. Dawes, G. S., H. E. Fox, B. M. Leduc, G. C. Liggins, and R. T. Richards. Respiratory movements and rapid eye movement sleep in the foetal lamb. J. Physiol. London 220: 119–143, 1972.
 163. Decima, E. E., and C. von Euler. Intercostal and cerebellar influences on efferent phrenic activity in the decerebrate cat. Acta Physiol. Scand. 76: 148–158, 1969.
 164. Decima, E. E., C. von Euler, and, U. Thoden. Intercostal‐to‐phrenic reflexes in the spinal cat. Acta Physiol. Scand. 75: 568–579, 1969.
 165. Dejours, P. Chemoreflexes in breathing. Physiol. Rev. 42: 335–358, 1962.
 166. Dejours, P. Control of respiration in muscular exercise. In: Handbook of Physiology. Respiration, edited by W. O. Fenn and H. Rahn. Washington, DC: Am. Physiol. Soc., 1964, sect. 3, vol. I, p. 631–648.
 167. Dejours, P. Principles of Comparative Respiratory Physiology. Amsterdam: North‐Holland, 1979.
 168. Dejours, P. Hiérarchie des régulations physiologiques: exemple des régulations respiratoires. In: La Transmission Neuro‐musculaire. Les Médiateurs et le “Milieu intérieur”, edited by P. DeJours. Paris: Masson, 1980, p. 275–287.
 169. Dempsey, J. A. Ventilatory control in changing ‘states’—exercise, sleep, and chronic hypoxia. In: Central Neural Production of Periodic Respiratory Movements, edited by J. L. Feldman and A. J. Berger. Evanston, IL: Northwestern Univ. Press, 1982, p. 19–24.
 170. Dempsey, J. A., and H. V. Forster. Mediation of ventilatory adaptations. Physiol. Rev. 62: 262–346, 1982.
 171. Dempsey, J. A., E. H. Vidruk, and S. M. Mastenbrook. Pulmonary control systems in exercise. Federation Proc. 39: 1498–1505, 1980.
 172. Denavit‐Saubié, M., and, J. Champagnat. The effect of some depressing amino acids on bulbar respiratory and non‐respiratory neurons. Brain Res. 97: 356–361, 1975.
 173. Denavit‐Saubié, M., J. Champagnat, and, W. Zieglgänsberger. Effects of opiates and methionine‐enkephalin on pontine and bulbar respiratory neurones of the cat. Brain Res. 155: 55–67, 1978.
 174. Denavit‐Saubié, M., and, D. Riche. Descending input from the pneumotaxic system to the lateral respiratory nucleus of the medulla. An anatomical study with the horseradish peroxidase technique. Neurosci. Lett. 6: 121–126, 1977.
 175. Denavit‐Saubié, M., D. Riche, J. Champagnat, and J. C. Velluti. Functional and morphological consequences of kainic acid microinjections into a pontine respiratory area of the cat. Neurosci. Lett. 5: 1609–1620, 1980.
 176. De Troyer, A., and, J. Rosso. Reflex inhibition of the diaphragm by esophageal afferents. Neurosci. Lett. 30: 43–46, 1982.
 177. De Troyer, A., M. Sampson, S. Sigrist, and P. T. Macklem. Action of costal and crural parts of the diaphragm on the rib cage in dog. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 53: 30–39, 1982.
 178. Dietrich, W. D., O. H. Lowry, and A. D. Loewy. The distribution of glutamate, GABA and aspartate in the nucleus tractus solitarius of the cat. Brain Res. 237: 254–260, 1982.
 179. DiMarco, A. F., C. von Euler, J. R. Romaniuk, and, Y. Yamamoto. Positive feedback facilitation of external intercostal and phrenic inspiratory activity by pulmonary stretch receptors. Acta Physiol. Scand. 113: 375–386, 1981.
 180. DiMarco, A. F., J. R. Romaniuk, C. von Euler, and, Y. Yamamoto. Immediate changes in ventilation and respiratory pattern associated with onset and cessation of locomotion in the rat. J. Physiol. London 343: 1–16, 1983.
 181. Dittler, R., and, S. Garten. Die zeitliche Folge der Aktionsstrome in Phrenicus und Zwerchfell bei der natürlichen Innervation. Z. Biol. 58: 420–450, 1912.
 182. Donoghue, S., R. B. Felder, D. Jordan, and K. M. Spyer. Brain stem projections of carotid baroceptors and chemoreceptors in the cat. J. Physiol. London 327: 48P, 1982.
 183. Donoghue, S., R. B. Felder, D. Jordan, and K. M. Spyer. The central projections of carotid baroreceptors and chemo‐receptors in the cat: a neurophysiological study. J. Physiol. London 347: 397–409, 1984.
 184. Donoghue, S., M. Garcia, D. Jordan, and K. M. Spyer. Identification and brain‐stem projections of aortic baroceptor afferent neurones in nodose ganglia of cats and rabbits. J. Physiol. London 322: 337–352, 1982.
 185. Donoghue, S., M. Garcia, D. Jordan, and K. M. Spyer. The brain‐stem projections of pulmonary stretch afferent neurons in cats and rabbits. J. Physiol. London 322: 352–364, 1982.
 186. Donoghue, S., S. M. Hilton, P. R. Smith, and R. J. Timms. Inputs from the brain stem defense areas to ventral medullary neurones in the cat. J. Physiol. London 319: 116P–117P, 1981.
 187. Duron, B. Activité électrique spontanée des muscles intercostaux et du diaphragme chez l'animal chronique. J. Physiol. Paris 61: 282–283, 1969.
 188. Duron, B. (editor). Respiratory Centres and Afferent Systems. Paris: INSERM, 1976.
 189. Duron, B. Intercostal and diaphragmatic muscle endings and afferents. In: Lung Biology in Health and Disease. Regulation of Breathing, edited by T. F. Hornbein. New York: Dekker, 1981, vol. 17, pt. I, chapt. 7, p. 473–540.
 190. Duron, B., M. C. Jung‐Caillol, and, D. Marlot. Effets des distensions etagées de l'oesophage thoracique sur l'activité spontanée du diaphragme chez le chat et le lapin. C. R. Acad. Sci. Paris Ser. D 281: 1863–1866, 1975.
 191. Duron, B., M. C. Jung–Caillol, and, D. Marlot. Myelinated nerve fiber supply and muscle spindles in the respiratory muscles of cat: quantitative study. Anat. Embryol. 152: 171–192, 1978.
 192. Duron, B., and, D. Marlot. The non‐myelinated fibers of the phrenic and the intercostal nerves in the cat. Z. Mikrosk. Anat. Forsch. 94: 257–268, 1980.
 193. Duron, B., D. Marlot, N. Larnicol, M. C. Jung‐Caillol, and J. M. Macron. Somatotopy in the phrenic motor nucleus of the cat as revealed by retrograde transport of horseradish peroxidase. Neurosci. Lett. 14: 159–163, 1979.
 194. Duron, B., D. Marlot, and J. M. Macron. Segmental motor innervation of the cat diaphragm. Neurosci. Lett. 15: 93–96, 1979.
 195. Eccles, R. M., T. A. Sears, and C. N. Shealy. Intracellular recording from respiratory motoneurons of the thoracic spinal cord of the cat. Nature London 193: 844–846, 1962.
 196. Eklund, G., C. von Euler, and, S. Rutkowski. Spontaneous and reflex activity of intercostal gamma motoneurones. J. Physiol. London 171: 139–163, 1964.
 197. Eldridge, F. L. Relationship between phrenic nerve activity and ventilation. Am. J. Physiol. 221: 535–543, 1971.
 198. Eldridge, F. L. The importance of timing on the respiratory effects of intermittent carotid body stimulation. J. Physiol. London 222: 297–318, 1972.
 199. Eldridge, F. L. Expiratory effects of brief carotid sinus nerve and carotid body stimulations. Respir. Physiol. 26: 295–310, 1976.
 200. Eldridge, F. L., P. Gill‐Kumar, D. E. Millhorn, and T. G. Waldrop. Spinal inhibition of phrenic motoneurones by stimulation of afferents from peripheral muscles. J. Physiol. London 311: 67–79, 1981.
 201. Eldridge, F. L., D. E. Milhorn, and, T. Waldrop. Exercise hyperpnea and locomotion: parallel activation from the hypothalamus. Science 211: 844–846, 1981.
 202. Ellenberger, H. H., J. C. Smith, D. R. McCrimmon, and J. L. Feldman. A projection from a discretely localized cell group near the ventral surface of the rostral medulla to the ventral respiratory group in the cat. Soc. Neurosci. Abstr. 11: 1143 1985.
 203. Errington, M. L., and M. R. Dashwood. Projection to the ventral surface of the cat brainstem demonstrated by horseradish peroxidase. Neurosci. Lett. 12: 153–158, 1979.
 204. Euler, C. von. The role of proprioceptive afferents in the control of respiratory muscles. Acta Neurobiol. Exp. 33: 329–341, 1973.
 205. Euler, C. von. On the central pattern generator for the basic breathing rhythmicity. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 55: 1647–1659, 1983.
 206. Euler, C. von, K. Budzinska, T. Panteleo, Y. Yamamoto, and F. F. Kao. Some organizational features of the respiratory pattern generator and its output as revealed by focal cold block of different medullary structures. In: Neurogenesis of Central Respiratory Rhythm: Electrophysiological, Pharmacological and Clinical Aspects, edited by A. L. Bianchi and M. Denavit‐Saubié. Lancaster, UK: MTP, 1985, p. 45–51.
 207. Euler, C. von, J. N. Hayward, I. Marttila, and R. J. Wyman. Respiratory neurones of the ventrolateral nucleus of the solitary tract of cat: vagal input, spinal connections and morphological identification. Brain Res. 61: 1–22, 1973.
 208. Euler, C. von, J. N. Hayward, I. Marttila, and R. J. Wyman. The spinal connections of the inspiratory neurones of the ventrolateral nucleus of the cat's tractus solitarius. Brain Res. 61: 23–33, 1973.
 209. Euler, C. von, F. Herrero, and, I. Wexler. Control mechanisms determining rate and depth of respiratory movements. Respir. Physiol. 10: 93–108, 1970.
 210. Euler, C. von, and H. Lagercrantz (editors). Central Nervous Control Mechanisms in Breathing. New York: Pergamon, 1979.
 211. Euler, C. von, I. Marttila, J. E. Remmers, and, T. Trippenbach. Effects of lesions in the parabrachial nucleus on the mechanisms for central and reflex termination of inspiration in the cat. Acta Physiol. Scand. 96: 324–337, 1976.
 212. Euler, C. von, and U. Soderberg. Slow potentials in the respiratory centres. J. Physiol. London 118: 555–564, 1952.
 213. Euler, C. von, and T. Trippenbach. Excitability changes of the inspiratory “off‐switch” mechanism tested by electrical stimulation in nucleus parabrachialis in the cat. Acta Physiol. Scand. 97: 175–188, 1976.
 214. Eyzaguirre, C., and J. R. Taylor. Respiratory discharge of some vagal motoneurons. J. Neurophysiol. 26: 61–78, 1963.
 215. Fedorko, L., and E. G. Merrill. Axonal projections from rostral expiratory neurones of the Botzinger complex to medulla and spinal cord in the cat. J. Physiol. London 350: 487–496, 1984.
 216. Fedorko, L., E. G. Merrill, and, J. Lipski. Two descending medullary inspiratory pathways to phrenic motoneurones. Neurosci. Lett. 43: 285–291, 1983.
 217. Feldman, J. L. A network model for control of inspiratory cutoff by the pneumotaxic center with supportive experimental data in cats. Biol. Cybern. 21: 131–138, 1976.
 218. Feldman, J. L. Interactions between brainstem inspiratory neurons. Federation Proc. 40: 2384–2388, 1981.
 219. Feldman, J. L. Background and themes for symposium on central neural production of periodic respiratory movements. In: Central Neural Production of Periodic Respiratory Movements, edited by J. L. Feldman and A. J. Berger. Evanston, IL: Northwestern Univ. Press, 1982, p. 2–4.
 220. Feldman, J. L., and A. J. Berger (editors). Central Neural Production of Periodic Respiratory Movements. Evanston, IL: Northwestern Univ. Press, 1982.
 221. Feldman, J. L., and C. L. Cleland. Possible roles of pacemaker neurons in mammalian respiratory rhythmogenesis. In: Cellular Pacemakers, edited by D. O. Carpenter. New York: Wiley, vol. II., 1982, p. 101–119.
 222. Feldman, J. L., and M. I. Cohen. Relation between expiratory duration and rostral medullary expiratory neuronal discharge. Brain Res. 141: 172–178, 1978.
 223. Feldman, J. L., M. I. Cohen, and, P. Wolotsky. Phasic pulmonary afferent activity drastically alters the respiratory modulation of neurons in the rostral pontine pneumotaxic center. In: Respiratory Centres and Afferent Systems, edited by B. Duron. Paris: INSERM, 1976, p. 95–105.
 224. Feldman, J. L., M. I. Cohen, and, P. Wolotsky. Powerful inhibition of pontine respiratory neurons by pulmonary afferent activity. Brain Res. 104: 341–346, 1976.
 225. Feldman, J. L., and J. D. Cowan. Large‐scale activity in neural nets. II. A model for the brainstem respiratory oscillator. Biol. Cybern. 17: 39–51, 1975.
 226. Feldman, J. L., and, H. Gautier. Interaction of pulmonary afferents and pneumotaxic center in control of respiratory pattern in cats. J. Neurophysiol. 39: 31–44, 1976.
 227. Feldman, J. L., and, S. Grillner. Control of vertebrate respiration and locomotion: a brief account. Physiologist 26: 310–316, 1983.
 228. Feldman, J. L., A. D. Loewy, and D. F. Speck. Projections from the ventral respiratory group to phrenic and intercostal motoneurons in cat: an autoradiographic study. J. Neurosci. 8: 1993–2000, 1985.
 229. Feldman, J. L., D. R. McCrimmon, and D. F. Speck. Effect of synchronous activation of medullary inspiratory bulbospinal neurones on phrenic nerve discharge in cat. J. Physiol. London 347: 241–254, 1984.
 230. Feldman, J. L., D. Sommer, and M. I. Cohen. Short time scale correlations between discharges of medullary respiratory neurons. J. Neurophysiol. 43: 1284–1295, 1980.
 231. Feldman, J. L., and D. F. Speck. Interactions among inspiratory neurons in dorsal and ventral respiratory groups in cat medulla. J. Neurophysiol. 49: 472–490, 1983.
 232. Fetz, E. E., and, B. Gustafsson. Relation between shapes of post‐synaptic potentials and changes in firing probability of cat motoneurones. J. Physiol. London 341: 387–410, 1983.
 233. Fitzgerald, R. S., H. Gautier, and, S. Lahiri. Regulation of respiration during sleep and anesthesia. Adv. Exp. Med. Biol. 99: 1–448, 1978.
 234. Flourens, M. J. P. Recherches expérimentales sur les propriétés et les fonctions du système nerveux dans les animaux vertébrés. Paris: Ballière, 1842.
 235. Flourens, M. J. P. Note sur le point vital de la moelle allongée. C. R. Seances Soc. Biol. 33: 59–62, 1851.
 236. Folgering, H., and, F. Smolders. The steady state response of brainstem respiratory neuron activity to various levels of PaCO2 and PaO2. Pfluegers Arch. 383: 9–17, 1979.
 237. Folgering, H. T., F. D. Smolders, and J. A. Bernards. The role of the fusimotor system with respect to the contribution of the diaphragm and the intercostal muscles to the respiratory tidal volume. Pfluegers Arch. 366: 107–114, 1976.
 238. Fordyce, W. E., F. M. Bennet, S. K. Edelman, and F. S. Grodins. Evidence in man for a fast neural mechanism during the early phase of exercise hyperpnea. Respir. Physiol. 48: 27–43, 1982.
 239. Forster, H. V., and J. A. Dempsey. Ventilatory adaptations. In: Lung Biology in Health and Disease. Regulation of Breathing, edited by T. F. Hornbein. New York: Dekker, 1981, vol. 17, pt. 2, p. 845–904.
 240. Fourtner, C. R. Central control of cockroach walking. In: Neural Control of Locomotion, edited by R. H. Herman, S. Grillner, P. Stein, and D. G. Stuart. New York: Plenum, 1976.
 241. Friesen, W. O., and G. S. Stent. Neural circuits for generating rhythmic movements. Annu. Rev. Biophys. Bioeng. 7: 37–61, 1978.
 242. Frostig, R. D., Z. Frostig, and R. M. Harper. Information trains. The technique and its uses in spike train and network analysis, with examples taken from the nucleus parabrachialis medialis during sleep‐waking states. Brain Res. 322: 67–74, 1984.
 243. Fukuda, Y., and, Y. Honda. pH‐sensitive cells at ventrolateral surface of rat medulla oblongata. Nature London 256: 317–318, 1975.
 244. Fukuda, Y., and, Y. Honda. pH sensitivity of cells located at the ventrolateral surface of the cat medulla oblongata in vitro. Pfluegers Arch. 364: 243–247, 1976.
 245. Fukuda, Y., Y. Honda, M. E. Schläfke, and H. H. Loeschcke. Effect of H+ on the membrane potential of silent cells in the ventral and dorsal surface layers of the rat medulla in vitro. Pfluegers Arch. 376: 229–235, 1978.
 246. Fukuda, Y., and H. H. Loeschcke. Effect of H+ on spontaneous neuronal activity in the surface layer of the rat medulla oblongata in vitro. Pfluegers Arch. 371: 125–134, 1977.
 247. Gacek, R. R., and M. J. Lyon. Fiber components of the recurrent laryngeal nerve in the cat. Ann. Otol. Rhinol. Laryngol. 85: 460–471, 1976.
 248. Gacek, R. R., L. T. Malmgren, and M. J. Lyon. Localization of adductor motor nerve fibers to the larnyx. Ann. Otol. Rhinol. Laryngol. 86: 770–776, 1977.
 249. Galen. Usefulness of the Parts of the Body, edited by M. T. May. Ithaca, NY: Cornell Univ. Press, 1968.
 250. Gardner, W. N. The relation between tidal volume and inspiratory and expiratory times during steady‐state carbon dioxide inhalation in man. J. Physiol. London 272: 591–611, 1977.
 251. Gardner, W. N. The pattern of breathing following step changes of alveolar partial pressures of carbon dioxide and oxygen in man. J. Physiol. London 300: 55–73, 1980.
 252. Gasser, H. S. The analysis of individual waves in the phrenic electroneurogram. Am. J. Physiol. 85: 569–576, 1928.
 253. Gasser, H. S., and H. S. Newcomer. Physiological action currents in the phrenic nerve, an application of the thermionic vacuum tube to nerve physiology. Am. J. Physiol. 57: 1–26, 1921.
 254. Gauthier, P., J. C. Barillot, and, M. Dussardier. Mise en évidence électrophysiologique de bifurcations d'axone dans le nerf récurrent laryngé. J. Physiol. Paris 76: 39–48, 1980.
 255. Gauthier, P., J. C. Barillot, and, M. Dussardier. Mise en évidence d'interactions d'orgine centrale entre motoneurones laryngés. J. Physiol. Paris 76: 647–661, 1980.
 256. Gauthier, P., R. Monteau, and, M. Dussardier. Inspiratory on‐switch evoked by mesencephalic stimulation. Exp. Brain Res. 51: 261–270, 1983.
 257. Gautier, H. Respiratory responses of the anesthetized rabbit to vagotomy and thoracic dorsal rhizotomy. Respir. Physiol. 17: 238–247, 1973.
 258. Gautier, H. Pattern of breathing during hypoxia or hypercapnia of the awake or anesthetized cat. Respir. Physiol. 27: 193–206, 1976.
 259. Gautier, H. Control of the pattern of breathing. Clin. Sci. 58: 343–348, 1980.
 260. Gautier, H., and, F. Bertrand. Respiratory effects of pneumotaxic center lesions and subsequent vagotomy in chronic cats. Respir. Physiol. 23: 71–85, 1975.
 261. Gautier, H., and, M. Bonora. Effects of carotid body denervation on respiratory pattern of awake cats. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 46: 1127–1131, 1979.
 262. Gautier, H., M. Bonora, and J. H. Gaudy. Breuer‐Hering inflation reflex and breathing pattern in anesthetized humans and cats. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 51: 1162–1168, 1981.
 263. Gautier, H., J. E. Remmers, and D. Bartlett Jr.. Control of the duration of expiration. Respir. Physiol. 18: 205–221, 1973.
 264. Geman, S., and, M. Miller. Computer simulation of brainstem respiratory activity. J. Appl. Physiol. 41: 931–938, 1976.
 265. Gesell, R. A. Neurophysiological interpretation of the respiratory act. Ergeb. Physiol. Biol. Chem. Exp. Pharmakol. 43: 477–639, 1940.
 266. Gesell, R., J. Bricker, and, C. Magee. Structural and functional organization of the central mechanism controlling breathing. Am. J. Physiol. 117: 423–452, 1936.
 267. Gill, P. K. The effects of end‐tidal CO2 on the discharge of individual phrenic motoneurones. J. Physiol. London 168: 239–257, 1963.
 268. Gill, P. K., and, M. Kuno. Properties of phrenic motoneurones. J. Physiol. London 168: 258–273, 1963.
 269. Gill, P. K., and, M. Kuno. Excitatory and inhibitory actions on phrenic motoneurones. J. Physiol. London 168: 274–289, 1963.
 270. Glenn, L. L., and W. C. Dement. Membrane potential, synaptic activity, and excitability of hindlimb motoneurons during wakefulness and sleep. J. Neurophysiol. 46: 839–854, 1981.
 271. Glenn, W. W. L., B. Haak, C. Sasaki, and, J. Kirchner. Characteristics and surgical management of respiratory complications accompanying pathologic lesions of the brain stem. Ann. Surg. 191: 655–663, 1980.
 272. Gold, M. R., and A. R. Martin. Intracellular Cl‐accumulation reduces Cl− conductance in inhibitory synaptic channels. Nature London 299: 828–830, 1982.
 273. Goldman, M. D. Functional behavior of the respiratory muscles. In: Central Neural Production of Periodic Respiratory Movements, edited by J. L. Feldman and A. J. Berger. Evanston, IL: Northwestern Univ. Press, 1982, p. 11–14.
 274. Goodman, N. W. Efferent inhibition of arterial chemoreceptors and stimulation of the sinus nerve. In: The Peripheral Arterial Chemoreceptors, edited by M. J. Purves. Cambridge, UK: Cambridge Univ. Press, 1975, p. 241–252.
 275. Gootman, P. M., and M. I. Cohen. Efferent splanchnic activity and systemic arterial pressure. Am. J. Physiol. 219: 897–903, 1970.
 276. Goshgarian, H. G., and J. A. Rafols. The phrenic nucleus of the albino rat: a correlative HRP and Golgi study. J. Comp. Neurol. 201: 441–456, 1981.
 277. Goshgarian, H. G., and J. A. Rafols. The ultrastructure and synaptic architecture of phrenic motoneurons in the spinal cord of the adult cat. J. Neurocytol. 13: 85–109, 1984.
 278. Graham, K., and, J. Duffin. Cross‐correlation of medullary dorsomedial inspiratory neurons in the cat. Exp. Neurol. 75: 627–643, 1982.
 279. Grillner, S. Control of locomotion in bipeds, tetrapods, and fish. In: Handbook of Physiology. The Nervous System. Motor Control, edited by J. M. Brookhart and V. B. Mountcastle. Bethesda, MD: Am. Physiol. Soc., 1981, sect. 1, vol. II, pt. 2, chapt, 26, p. 1179–1236.
 280. Grodins, F. S. Models. In: Lung Biology in Health and Disease. Regulation of Breathing, edited by T. F. Hornbein. New York: Dekker, 1981, vol. 17, pt. 2, p. 1313–1351.
 281. Gromysz, H., and W. A. Karczewski. Respiratory neurons of the ventral respiratory nucleus of the rabbit and their vagal connections. Acta Neurobiol. Exp. 36: 581–592, 1976.
 282. Gromysz, H., and W. A. Karczewski. Generation of respiratory pattern in the rabbit—brainstem transections revisited. Acta Neurobiol. Exp. 40: 985–992, 1980.
 283. Gromysz, H., and W. A. Karczewski. Phrenic motoneurone activity in split‐brainstem cats and monkeys. Respir. Physiol. 50: 51–61, 1982.
 284. Gromysz, H., W. A. Karczewski, E. Naslonska, K. Ruszczyk, and, K. Sroczynska. Effects of reversible elimination of some bulbar structures on the generation of respiratory pattern in rabbits. Acta. Neurobiol. Exp. 40: 507–514, 1980.
 285. Gustafsson, B., and, D. McCrea. Influence of stretch‐evoked synaptic potentials on firing probability of cat spinal motoneurones. J. Physiol. London 347: 431–451, 1984.
 286. Haber, E., K. W. Kohn, S. H. Ngai, D. A. Holaday, and S. C. Wang. Localization of spontaneous respiratory neuronal activities in the medulla oblongata of the cat: a new location of the expiratory center. Am. J. Physiol. 190: 350–355, 1957.
 287. Hackett, P. H., K. H. Maret, J. S. Milledge, R. M. Peters, C. J. Pizzo, J. B. West, and R. M. Winslow. Physiology of man on the summit of Mt. Everest. J. Physiol. London 334: 99P, 1983.
 288. Haddad, G. G., T. L. Lai, and R. B. Mellins. Determination of ventilatory pattern in REM sleep in normal infants. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 53: 52–56, 1982.
 289. Haller, A. V. Elementa Physiologiae Corporis Humani. Lausanne, Switzerland: Sigismiundi d'Arnay, 1761.
 290. Harding, R., P. Johnson, and M. E. McClelland. Respiratory function of the larynx in developing sheep and the influence of sleep state. Respir. Physiol. 40: 165–179, 1980.
 291. Harper, R. M., R. C. Frysinger, R. B. Trelease, and J. D. Marks. State‐dependent alteration of respiratory timing by stimulation of the central nucleus of the amygdala. Brain Res. 306: 1–8, 1984.
 292. Harper, R. M., and G. C. Sieck. Discharge correlations between neurons in the nucleus parabrachialis medialis during sleep‐waking states. Brain Res. 199: 343–358, 1980.
 293. Harper, R. M., and G. C. Sieck. The effect of sleep on brainstem respiratory neurons. In: Central Neural Production of Periodic Respiratory Movements, edited by J. L. Feldman and A. J. Berger. Evanston, IL: Northwestern Univ. Press, 1982, p. 81–82.
 294. Head, H. On the regulation of respiration. J. Physiol. London 10: 1–70, 1889.
 295. Henderson, V. E., and T. A. Sweet. On the respiratory centre. Am. J. Physiol. 91: 94–102, 1929.
 296. Herczynski, R., and, W. Karczewski. Neural control of breathing: a system analysis. Acta Physiol. Pol. 27: 109–130, 1976.
 297. Hering, E. Self‐steering of respiration through the nervus vagus [English transl.]. In: Breathing: Hering‐Breuer Centenary Symposium, edited by R. Porter. London: Churchill, 1970, p. 359–364.
 298. Heymans, C., and J. J. Bouckaert. Sinus carotidiens et réflexes respiratoires. I. C. R. Soc. Biol. 103: 498–500, 1930.
 299. Heymans, C., J. J. Bouckhaert, and, L. Dautrebande. Sinus carotidiens et réflexes de respiratoires. II. Influences respiratoires réflexes de l'acidose, de l'alcalose, de l'anhydride carbonique, de l'ion hydrogène et del l' anoxemie. Arch. Int. Pharmacodyn. 39: 400–447, 1930.
 300. Heymans, C., and, P. Rijlant. Le cournat d'action du nerf du sinus carotidien intact. C. R. Soc. Biol. 113: 69–73, 1933.
 301. Hickey, R. F., and J. W. Severinghaus. Regulation of breathing: drug effects. In: Lung Biology in Health and Disease. Regulation of Breathing, edited by T. F. Hornbein. New York: Dekker, 1981, vol. 17, pt. II, chapt. 21, p. 1251–1312.
 302. Hilaire, G., P. Gauthier, and, R. Monteau. Central drive and recruitment order of phrenic and inspiratory laryngeal motoneurones. Respir. Physiol. 51: 341–359, 1983.
 303. Hilaire, G., M. Khatib, and, R. Monteau. Spontaneous respiratory activity of phrenic and intercostal renshaw cells. Neurosci. Lett. 43: 97–101, 1983.
 304. Hilaire, G., and, R. Monteau. Activité des motoneurones phréniques au cours de la polypnee thermique ou hypocapnique. J. Physiol. Paris 68: 193–203, 1974.
 305. Hilaire, G., and, R. Monteau. Connexions entre les neurones inspiratoire bulbaires et les motoneurones phréniques et intercostaux. J. Physiol. Paris 72: 987–1000, 1976.
 306. Hilaire, G., and, R. Monteau. Facteurs déterminant l'ordre de recrutement des motoneurones phréniques. J. Physiol. Paris 75: 765–781, 1979.
 307. Hilaire, G., R. Monteau, and A. L. Bianchi. A cross‐correlation study of interactions among respiratory neurons of dorsal, ventral and retrofacial groups in cat medulla. Brain Res. 302: 19–31, 1984.
 308. Hilaire, G., J. G. Nicholls, and T. A. Sears. Central and proprioceptive influences on the activity of levator costae motoneurones in the cat. J. Physiol. London 342: 527–548, 1983.
 309. Hildebrandt, J. R. Intracellular activity of medullary respiratory neurons. Exp. Neurol. 45: 298–313, 1974.
 310. Hill, P., E. W. Huges, and J. D. Sinclair. The relationship between respiratory stimulation by the superficial medullary cholinergic mechanism and by inspired carbon dioxide in anaesthetized rats. J. Physiol. London 334: 42P, 1983.
 311. Hilton, S. M. The defense‐arousal system and its relevance for circulatory and respiratory control. J. Exp. Biol. 100: 159–174, 1982.
 312. Hinsey, J. C., K. Hare, and R. A. Phillips. Sensory components of the phrenic nerve of the cat. Proc. Soc. Exp. Biol. Med. 41: 411–414, 1939.
 313. Hoff, H. E., and C. G. Breckenridge. The medullary origin of respiratory periodicity in the dog. Am. J. Physiol. 158: 157–172, 1949.
 314. Hoff, H. E., and C. G. Breckenridge. Levels of integration of respiratory patterns. J. Neurophysiol. 15: 47–56, 1952.
 315. Holstege, G. Anatomical evidence for two brainstem‐spinal pathways especially related to supraspinal control of respiratory functions in the cat. An autoradiographical study. Neurosci. Lett. Supp. 7: S207, 1981.
 316. Holstege, G., H. G. Kuypers, and J. J. Dekker. The organisation of the bulbar fibre connections to the trigeminal, facial and hypoglossal motor nuclei. II. An autoradiographic tracing study in cat. Brain 100: 264–286, 1977.
 317. Hornbein, T. F. Lung Biology in Health and Disease. Regulation of Breathing, New York: Dekker, 1981, vol. 17, pt. 1 and 2.
 318. Hugelin, A. Does the respiratory rhythm originate from a reticular oscillator in the waking state? In: The Reticular Formation Revisited, edited by J. A. Hobson and M. A. B. Brazier. New York: Raven, 1980, p. 261–274.
 319. Hugelin, A., and M. I. Cohen. The reticular activating system and respiratory regulation in the cat. Ann. NY Acad. Sci. 109: 586–603, 1963.
 320. Hukahara, T. Jr.. Functional organization of brain stem respiratory neurons and its afferences. In: Respiratory Centres and Afferent Systems, edited by B. Duron. Paris: INSERM, 1976, p. 41–53.
 321. Hukahara, T., S. Nakayama, and, H. Okada. Action potentials in the normal respiratory centers and its centrifugal pathways in the medulla oblongata and spinal cord. Jpn. J. Physiol. 4: 145–153, 1954.
 322. Huszczuk, A. A respiratory pump controlled by phrenic nerve activity. J. Physiol. London 210: 183P, 1970.
 323. Huszczuk, A., L. Jankowska, I. Kulesza, P. M. Ryba. Studies on reflex control of breathing in pigs and baboons. Acta Neurobiol. Exp. 37: 275–293, 1977.
 324. Iscoe, S. Pulmonary stretch receptor discharge patterns in eupnea, hypercapnia, and hypoxia. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 53: 346–354, 1982.
 325. Iscoe, S., J. Dankoff, R. Mikgicovsky, and, C. Polosa. Recruitment and discharge frequency of phrenic motoneurones during inspiration. Respir. Physiol. 26: 113–128, 1976.
 326. Iscoe, S., J. L. Feldman, and M. I. Cohen. Properties of inspiratory termination by superior laryngeal and vagal stimulation. Respir. Physiol. 36: 353–366, 1979.
 327. Iscoe, S., and, C. Polosa. Synchronization of respiratory frequency by somatic afferent stimulation. J. Appl. Physiol. 40: 138–148, 1976.
 328. Jan, Y. N., L. Y. Jan, and S. W. Kuffler. A peptide as a possible transmitter in sympathetic ganglia of the frog. Proc. Natl. Acad. Sci. USA 76: 1501–1505, 1979.
 329. Jansen, A. H., and, V. Chernick. Development of respiratory control. Physiol. Rev. 63: 437–483, 1983.
 330. Kahn, N., and S. C. Wang. Pontine pneumotaxic center and central respiratory rhythm. Am. J. Physiol. 211: 520–524, 1966.
 331. Kalia, M. Neuroanatomical organization of the respiratory centers. Federation Proc. 36: 2405–2411, 1977.
 332. Kalia, M., J. L. Feldman, and M. I. Cohen. Afferent projections to inspiratory neuronal region of the ventrolateral nucleus of the tractus solitarius in the cat. Brain Res. 171: 135–141, 1979.
 333. Kao, F. F., and L. H. Ray. Respiratory and circulatory responses of anesthetized dogs to induced muscular work. Am. J. Physiol. 179: 249–254, 1954.
 334. Karczewski, W. A. Organization of the brain stem respiratory complex. In: Respiratory Physiology (MTP Int. Rev. Sci.‐Physiol. Ser.: Vol. 2), edited by J. G. Widdicombe. London: Butterworths, 1974, p. 197–219.
 335. Karczewski, W. A., and, H. Gromysz. The “split respiratory centre,” lessons from brainstem transections. In: Advances in Physiological Sciences. Respiration, edited by I. Hutas and L. A. Debreczeni. Budapest: Akad. Kiado, 1981, vol. 10, p. 587–594.
 336. Karczewski, W. A., E. Naslonska, and J. R. Romaniuk. Inspiratory facilitatory and inhibitory vagal influences during apnea in rabbits. Acta Neurobiol. Exp. 40: 575–59, 1980.
 337. Karczewski, W. A., and J. R. Romaniuk. Neural control of breathing and central nervous system plasticity. Acta Physiol. Pol. 31: 1–10, 1980.
 338. Karczewski, W. A., and J. G. Widdicombe. Neural control of breathing. Acta Neurobiol. Exp. 33: 1–432, 1973.
 339. Keder‐Stepanova, I. A. Characteristics of the respiratory neurons of different levels of the central nervous system. In: Models of Structural‐Functional Organization of Certain Biological Systems, edited by I. M. Gelfand. Cambridge, MA: MIT Press, 1971, p. 193–232.
 340. Keder‐Stepanova, I. A., and A. P. Chetayev. Structure of the links of two zones of the respiratory centre of the medulla oblongata. Biofizika 15: 717–722, 1970.
 341. Kellogg, R. H. Historical perspectives. In: Lung Biology in Health and Disease. Regulation of Breathing, edited by T. F. Hornbein. New York: Dekker, 1981, vol. 17, pt. 1, chapt. 1, p. 3–66.
 342. Keswani, N. H. The phrenic nucleus. III. Organization of the phrenic nucleus in the spinal cord of the cat and man. Proc. Staff Meet. Mayo Clin. 30: 566–677, 1955.
 343. King, G. W. Brain stem blood vessels and the organization of the lateral reticular formation in the medulla oblongata of the cat. Brain Res. 191: 253–259, 1980.
 344. King, G. W. Topology of ascending brainstem projections to nucleus parabrachialis in the cat. J. Comp. Neurol. 191: 615–638, 1980.
 345. King, G. W., and C. K. Knox. An electrophysiological study of medullary neurons projecting to nucleus parabrachialis of the cat. Brain Res. 236: 27–33, 1982.
 346. King, G. W., and C. K. Knox. Types and locations of respiratory‐related neurons in lateral tegmental field of cat medulla oblongata. Brain Res. 295: 301–315, 1984.
 347. King, G. W., and C. K. Knox. Types and locations of respiratory‐related neurons in lateral tegmental field of cat medulla oblongata. Brain Res. 295: 301–315, 1984.
 348. Kirkwood, P. A. On the use and interpretation of cross‐correlation measurements in the mammalian central nervous system. J. Neurosci. Meth. 1: 107–132, 1979.
 349. Kirkwood, P. A., N. Nisimaru, and T. A. Sears. Monosynaptic excitation of bulbospinal neurones by chemoreceptor afferents in the carotid sinus nerve. J. Physiol. London 293: 35P–36P, 1979.
 350. Kirkwood, P. A., and T. A. Sears. Proceedings: monosynaptic excitation of thoracic expiratory motoneurones from lateral respiratory neurones in the medulla of the cat. J. Physiol. London 234: 87P–89P, 1973.
 351. Kirkwood, P. A., and T. A. Sears. The synaptic connexions to intercostal motoneurones as revealed by the average common excitation potential. J. Physiol. London 275: 103–134, 1978.
 352. Kirkwood, P. A., and T. A. Sears. Comparison between unitary excitatory post‐synaptic potentials and cross‐correlation histograms for intercostal motoneurones. J. Physiol. London 295: 39P–40P, 1980.
 353. Kirkwood, P. A., and T. A. Sears. Excitatory post‐synaptic potentials from single muscle spindle afferents in external intercostal motoneurones of the cat. J. Physiol. London 322: 287–314, 1982.
 354. Kirkwood, P. A., and T. A. Sears. The effects of single afferent impulses on the probability of firing of external intercostal motoneurones in the cat. J. Physiol. London 322: 315–336, 1982.
 355. Kirkwood, P. A., T. A. Sears, and, D. Stagg. Proceedings: synchronised firing of respiratory motoneurones during spontaneous breathing in the anaesthetised cat. J. Physiol. London 239: 11P–13P, 1974.
 356. Kirkwood, P. A., T. A. Sears, D. Stagg, and R. H. Westgaard. The spatial distribution of synchronisation of intercostal motoneurones in the cat. J. Physiol. London 327: 137–155, 1982.
 357. Kirkwood, P. A., T. A. Sears, D. L. Tuck, and R. H. Westgaard. Variations in the time course of the synchronisation of intercostal motoneurones in the cat. J. Physiol. London 327: 105–135, 1982.
 358. Kirkwood, P. A., T. A. Sears, and R. H. Westgaard. Recurrent inhibition of intercostal motoneurones in the cat. J. Physiol. London 319: 111–130, 1981.
 359. Kling, U., and, G. Szekely. Simulation of rhythmic nervous activities. I. Function of networks with cyclic inhibitions. Kybernetik 5: 89–103, 1968.
 360. Knill, R., and A. C. Bryan. An intercostal‐phrenic inhibitory reflex in human newborn infants. J. Appl. Physiol. 40: 352–356, 1976.
 361. Knox, C. K. Characteristics of inflation and deflation reflexes during expiration in the cat. J. Neurophysiol. 36: 284–295, 1973.
 362. Knox, C. K. Cross‐correlation functions for a neuronal model. Bipohys. J. 14: 567–582, 1974.
 363. Knox, C. K., and G. W. King. Changes in the Breuer‐Hering reflexes following rostral pontine lesion. Respir. Physiol. 28: 189–206, 1976.
 364. Knox, C. K., and R. E. Poppele. Correlation analysis of stimulus‐evoked changes in excitability of spontaneously firing neurons. J. Neurophysiol. 40: 616–625, 1977.
 365. Koepchen, H. P., D. Klussendorf, H. Lazar, and, T. Hukuhara. Conclusions on respiratory rhythmogenesis drawn from lesion and cooling experiments predominantly in the region of ventrolateral nucleus of solitary tract (vlNTS). In: Neurogenesis of Central Respiratory Rhythm: Electrophysiological, Pharmacological and Clinical Aspects, edited by A. L. Bianchi and M. Denavit‐Saubié. Lancaster, UK: MTP Press, 1985, p. 77–80.
 366. Koepchen, H. P., D. Klussendorf, and, U. Phillipp. Mechanisms of central transmission of respiratory reflexes. Acta. Neurobiol. Exp. 33: 287–299, 1973.
 367. Koepchen, H. P., H. Lazar, and, J. Borchert. On the role of the nucleus infrasolitarius in the determination of respiratory periodicity. Proc. Int. Congr. Physiol. Sci., 26th, New Delhi, 1974, vol. 11, p. 81.
 368. Kreidl, A. Ueber die Wechselbeziehungen der centren fur die Kehlkopfathmung. Pfluegers Arch. 74: 181–192, 1899.
 369. Kreuter, F., D. W. Richter, H. Camerer, and, R. Senekowitsch. Morphological and electrical description of medullary respiratory neurons of the cat. Pfluegers Arch., 372: 7–16, 1977.
 370. Krieger, A. J., H. D. Christensen, H. N. Sapru, and S. C. Wang. Changes in ventilatory patterns after ablation of various respiratory feedback mechanisms. J. Appl. Physiol. 33: 431–435, 1972.
 371. Krnjević, K., M. Randić, and B. K. Siesjö. Cortical CO2 tension and neuronal excitability. J. Physiol. London 176: 105–122, 1965.
 372. Kubin, L., and, J. Lipski. Properties of reversible graded inhibition of phrenic nerve activity by pulmonary afferents. Acta Physiol. Pol. 30: 571–579, 1979.
 373. Kuffler, S. W. Slow synaptic responses in autonomic ganglia and the pursuit of peptidergic transmitter. J. Exp. Biol. 89: 257–286, 1980.
 374. Kuzuhara, S., and S. M. Chou. Localization of the phrenic nucleus in the rat: a HRP study. Neurosci. Lett. 16: 119–124, 1980.
 375. Lahiri, S., and R. G. Delaney. Relationship between carotid chemoreceptor activity and ventilation in cat. Respir. Physiol. 24: 267–286, 1975.
 376. Lahiri, S., and, R. Gelfand. Mechanisms of acute ventilatory responses. In: Lung Biology in Health and Disease. Regulation of Breathing, edited by T. Hornbein. New York: Dekker, 1981, vol. 17, pt. 2, chapt. 12, p. 773–843.
 377. Lahiri, S., A. Mokashi, R. G. Delaney, and A. P. Fishman. Arterial PO2 and PCO2 stimulus threshold for carotid chemoreceptors in breathing. Respir. Physiol. 34: 359–375, 1978.
 378. Lamb, T. W. Ventilatory responses to hind limb exercise in anesthetized cats and dogs. Respir. Physiol. 6: 88–104, 1968.
 379. Landau, B. R., K. Akert, and T. S. Roberts. Studies on the innervation of the diaphragm. J. Comp. Neurol. 119: 1–10, 1962.
 380. Langendorff, O. Studien uber die Innervation der Atembewegungen. Arch. Physiol. 3: 518–549, 1880.
 381. Larnicol, N., D. Rose, D. Marlot, and, B. Duron. Spinal localisation of the intercostal motoneurones innervating the upper thoracic spaces. Neurosci. Lett. 31: 13–18, 1982.
 382. Larrabee, M. G., and, R. Hodes. Cyclic change in the respiratory centers, revealed by the effects of afferent impulses. Am. J. Physiol. 155: 147–164, 1948.
 383. Larrabee, M. G., and G. C. Knowlton. Excitation and inhibition of phrenic motoneurones by inflation of the lungs. Am. J. Physiol. 147: 90–99, 1946.
 384. Lawn, A. M. The localization, in the nucleus ambigus of the rabbit, of the cells of origin of motor nerve fibers in the glossopharyngeal nerve and various branches of the vagus nerve by means of retrograde degeneration. J. Comp. Neurol. 127: 293–306, 1966.
 385. Legallois, M. Experiments on the Principle of Life. Philadelphia, PA: M. Thomas, 1813.
 386. Leusen, I. Regulation of cerebrospinal fluid composition with reference to breathing. Physiol. Rev. 52: 1–56, 1972.
 387. Lewis, G., J. Ponte, and M. J. Purves. Fluctuations of Pa, CO2 with the same period as respiration in the cat. J. Physiol. London 298: 1–11, 1980.
 388. Lipscomb, W. T., and L. L. Boyarsky. Neurophysiological investigations of medullary chemosensitive areas of respiration. Respir. Physiol. 16: 362–376, 1972.
 389. Lipski, J. Antidromic activation of neurons as an analytic tool in the study of the central nervous system. J. Neurosci. Meth. 4: 1–32, 1981.
 390. Lipski, J. Brainstem microstimulation and microlesion; some critical remarks. In: Central Neural Production of Periodic Respiratory Movements, edited by J. L. Feldman and A. J. Berger. Evanston, IL: Northwestern Univ. Press, 1982, p. 190–194.
 391. Lipski, J. Is there electrical coupling between phrenic motoneurons in cats?. Neurosci. Lett. 46: 229–234, 1984.
 392. Lipski, J., R. E. W. Fyffe, and, J. Jodowski. Recurrent inhibition in the control of respiratory neurons. In: Neurogenesis of Central Respiratory Rhythm: Electrophysiological, Pharmacological and Clinical Aspects, edited by A. L. Bianchi and M. Denavit‐Saubié. Lancaster, UK: MTP, 1985, p. 198–205.
 393. Lipski, J., and, L. Kubin. Spinal projection of dorsal RB respiratory neurons—a reinvestigation of the problem. In: Central Neural Production of Periodic Respiratory Movements. edited by J. L. Feldman and A. J. Berger. Evanston, IL: Northwestern Univ. Press, 1982, p. 195–196.
 394. Lipski, J., L. Kubin, and, J. Jodkowski. Synaptic action of RP neurons on phrenic motoneurons studied with spike‐triggered averaging. Brain Res. 288: 105–118, 1983.
 395. Lipski, J., R. M. McAllen, and K. M. Spyer. The carotid chemoreceptor input to the respiratory neurones of nucleus of tractus solitarius. J. Physiol. London 269: 797–810, 1977.
 396. Lipski, J., and E. G. Merrill. Electrophysiological demonstration of the projection from expiratory neurones in rostral medulla to contralateral dorsal respiratory group. Brain Res. 197: 521–524, 1980.
 397. Lipski, J., A. Trzebski, and, L. Kubin. Excitability change of dorsal inspiratory neurons during lung inflations as studied by measurement of antidromic invasion latencies. Brain Res. 161: 25–38, 1979.
 398. Loeschcke, H. H. Central chemosensitivity and the reaction theory. J. Physiol. London 332: 1–24, 1982.
 399. Loeschcke, H. H., J. De Lattre, M. E. Schläfke, and C. O. Trouth. Effects on respiration and circulation of electrically stimulating the ventral surface of the medulla oblongata. Respir. Physiol. 10: 184–197, 1970.
 400. Loeschcke, H. H., M. E. Schlaefke, W. R. See, and, A. Herker‐See. Does CO2 act on the respiratory centers? Pfluegers Arch. 381: 249–254, 1979.
 401. Loewy, A. D., and, H. Burton. Nuclei of the solitary tract: efferent projections to the lower brain stem and spinal cord of the cat. J. Comp. Neurol. 181: 421–450, 1978.
 402. Loewy, A. D., J. H. Wallach, and, S. McKeller. Efferent connections of the ventral medulla oblongata in the rat. Brain Res. Rev. 3: 63–80, 1981.
 403. Lorry, M. Les mouvements du cerveau. Mem. Math. Phys. Pres. Acad. Rou. Sci. Div. Sav. Paris 3: 344–377, 1760.
 404. Lumsden, T. Observations on the respiratory centres in the cat. J. Physiol. London 57: 153–160, 1923.
 405. Luschei, E. S., and L. J. Goldberg. Neural mechanisms of mandibular control: mastication and voluntary biting. In: Handbook of Physiology. The Nervous System. Motor Control, edited by V. B. Brooks. Bethesda, MD.: Am. Physiol. Soc., 1982, sect. 1, vol. II, pt. 2, chapt. 27, p. 1237–1274.
 406. Luscher, H. R., K. Greeff, and, C. Hess. Die Rhythmogese der Atmung beschrieben mit Hilfe des Lotka‐Volterra‐Modells: Experimente und Simulation. Biol. Cybern. 26: 81–91, 1977.
 407. Luscher, H. R., E. Henneman, and, J. Mathis. Transmission failure at la synapses on cat spinal motoneurons. Neurosci. Suppl. 7: 135 1982.
 408. Luscher, H. R., P. Ruenzel, and, E. Henneman. How the size of motoneurones determines their susceptibility to discharge. Nature London 282: 859–861, 1979.
 409. Lüscher, H.‐R., P. Ruenzel, and, E. Henneman. Composite EPSPs in motoneurons of different sizes before and during PTP: implications for transmission failure and its relief in Ia projections. J. Neurophysiol. 49: 269–289, 1983.
 410. Lydic, R., and, J. Orem. Respiratory neurons of the pneumotaxic center during sleep and wakefulness. Neurosci. Lett. 15: 187–192, 1979.
 411. Madden, K. P., and J. E. Remmers. Short time scale correlations between spike activity of neighboring respiratory neurons of nucleus tractus solitarius. J. Neurophysiol. 48: 749–760, 1982.
 412. Madison, D. V., and R. A. Nichol. Noradrenaline blocks accomodation of pyramid cell discharge in the hippocampus. Nature London 299: 636–638, 1982.
 413. Malcolm, J. L., I. H. Sarelius, and J. D. Sinclair. The respiratory role of the ventral surface of the medulla studied in the anesthetized rat. J. Physiol. London 307: 503–515, 1980.
 414. Marino, P. L., R. O. Davies, and A. I. Pack. The responses of Ib cells to increases in the rate of lung inflation. Brain Res. 219: 289–305, 1981.
 415. Marino, P. L., and T. W. Lamb. Effects of CO2 and extracellular H+ iontophoresis on single cell activity in the cat brainstem. J. Appl. Physiol. 38: 688–695, 1975.
 416. Marckwald, M. Die Athembewegungen und deren Innervation beim Kaninchen. Z. Biol. 23: 149–283, 1887.
 417. Marckwald, M. Die Bedeutung des Mittelhirns fur die Athmung. Z. Biol. 26: 259–289, 1890.
 418. Marlott, D., and, B. Duron. Postnatal development of vagal control of breathing in the kitten. J. Physiol. Paris 75: 891–900, 1979.
 419. Marsh, J., and P. C. G. Nye. The reflex respiratory effects on cats of breathing through a tube. J. Physiol. London 325: 353–362, 1982.
 420. Maskrey, M., D. Megirian, and S. C. Nicol. Effects of decortication and carotid sinus nerve section on ventilation of the rat. Respir. Physiol. 43: 263–273, 1981.
 421. McCoy, K. S., C. F. Koopmann, Jr., and L. M. Taussig. Sleep‐related breathing disorders. Am. J. Otolaryngol 2: 228–239, 1981.
 422. McCrimmon, D. R., D. F. Speck, and J. L. Feldman. Effect of antidromic activation of bulbospinal respiratory neurons on phrenic neural discharge. Soc. Neurosci. Abstr. 8: 725 1982.
 423. McCrimmon, D. R., D. F. Speck, and J. L. Feldman. Role of the dorsal respiratory group (DRG) in processing vagal and superior laryngeal nerve afferent in cat. Soc. Neurosci. Abstr. 10: 707 1984.
 424. McDonald, D. M. Peripheral chemoreceptors: structure‐function relationships of the carotid body. In: Lung Biology in Health and Disease. Regulation of Breathing, edited by T. F. Hornbein. New York: Dekker, 1981, vol. 17, pt. 1, chapt. 3, p. 105–319.
 425. McKellar, S., and A. D. Loewy. Efferent projections of the A1 catecholamine cell group in the rat: an autoradiographic study. Brain Res. 241: 11–29, 1982.
 426. Mead, J. How the respiratory pump works. In: Central Neural Production of Periodic Respiratory Movements, edited by J. L. Feldman and A. J. Berger. Evanston, IL: Northwestern Univ. Press, 1982, p. 5–7.
 427. Mehler, W. R. Subcortical afferent connections of the amygdala in the monkey. J. Comp. Neurol. 190: 733–762, 1980.
 428. Mendelson, M. Oscillator neurons in crustacean ganglia. Science 171: 1170–1173, 1971.
 429. Merrill, E. G. The lateral respiratory neurones of the medulla: their associations with nucleus ambiguus, nucleus retroambigualis, the spinal accessory nucleus and the spinal cord. Brain Res. 24: 11–28, 1970.
 430. Merrill, E. G. Antidromic activation of lateral respiratory neurones during their silent period. J. Physiol. London 241: 118P–119P, 1974.
 431. Merrill, E. G. Finding a respiratory function for the medullary respiratory neurons. In: Essays on the Nervous System, edited by R. Bellairs and E. G. Gray. Oxford, UK: Oxford Univ. Press, 1974, p. 451–486.
 432. Merrill, E. G. Preliminary studies on nucleus retroambigualis‐nucleus of the solitary tract interactions in cats. J. Physiol. London 244: 54P–55P, 1974.
 433. Merrill, E. G. Absence of correlations between lateral expiratory neurones in cats. J. Physiol. London 276: 33P–34P, 1978.
 434. Merrill, E. G. Where are the real respiratory neurons?. Federation Proc. 40: 2389–2394, 1981.
 435. Merrill, E. G. One source of the expiratory inhibition of phrenic motoneurones in the cat. J. Physiol. London 332: 79 1982.
 436. Merrill, E. G., and, L. Fedorko. Monosynaptic inhibition of phrenic motoneurons: a long descending projection from Botzinger neurons. J. Neurosci. 4: 2350–2353, 1984.
 437. Merrill, E. G., J. Lipski, and, L. Kubin. Origin of the expiratory inhibition of nucleus tractus solitarius inspiratory neurons. Brain Res. 263: 43–50, 1983.
 438. Mifflin, S., D. Ballantyne, S. Backman, and D. W. Richter. Evidence for calcium activated potassium conductance in medullary respiratory neurons. In: Neurogenesis of Central Respiratory Rhythm: Electrophysiological, Pharmacological and Clinial Aspects, edited by A. L. Bianchi and M. Denavit‐Saubié. Lancaster, UK: MTP Press, 1985, p. 179–182.
 439. Milic‐Emili, G., and J. M. Petit. Mechanical efficiency of breathing. J. Appl. Physiol. 15: 359–362, 1960.
 440. Miller, A. D., K. Ezure, and, I. Suzuki. Control of abdominal muscles by brain stem respiratory neurons in the cat. J. Neurophysiol 54: 155–167, 1985.
 441. Miller, A. J. Deglutition. Physiol. Rev. 62: 129–184, 1982.
 442. Miller, S., and P. D. Scott. The spinal locomotor generator. Exp. Brain Res. 30: 387–403, 1977.
 443. Millhorn, D. E., F. L. Eldridge, and J. P. Kiley. Oscillations of medullary extracellular fluid pH caused by breathing. Respir. Physiol. 55: 193–204, 1984.
 444. Millhorn, D. E., F. L. Eldridge, and T. G. Waldrop. Effects of medullary area I(s) cooling on respiratory response to chemoreceptor inputs. Respir. Physiol. 49: 23–29, 1982.
 445. Mitchell, G. S., B. A. Cross, T. Hiramoto, and, P. Scheid. Mechanosensory‐chemosensory interactions in modulation phrenic nerve activity. In: Central Neural Production of Periodic Respiratory Movements, edited by J. L. Feldman and A. J. Berger. Evanston, IL: Northwestern Univ. Press, 1982, p. 111–112.
 446. Mitchell, R. A. Location and function of medullary respiratory neurons. Am. Rev. Respir. Dis. 115: 209–216, 1977.
 447. Mitchell, R. A., and A. J. Berger. Neural regulation of respiration. Am. Rev. Respir. Dis. 111: 206–224, 1975.
 448. Mitchell, R. A., and A. J. Berger. Neural regulation of respiration. In: Lung Biology in Health and Disease. Regulation of Breathing, edited by T. F. Hornbein. New York: Dekker, 1981, vol. 17, pt. 1, chapt. 8, p. 541–620.
 449. Mitchell, R. A., and D. A. Herbert. The effect of carbon dioxide on the membrane potential of medullary respiratory neurons. Brain Res. 75: 345–349, 1974.
 450. Mitchell, R. A., and D. A. Herbert. Synchronized high frequency synaptic potentials in medullary respiratory neurons. Brain Res. 75: 350–355, 1974.
 451. Mitchell, R. A., H. H. Loeschcke, W. H. Massion, and J. W. Severinghaus. Respiratory responses mediated through superficial chemosensitive areas on the medulla. J. Appl. Physiol. 18: 523–533, 1963.
 452. Mizuno, N., S. Nomura, and, Y. Takeuchi. The parabrachial nucleus as an intermediate relay station of the visceral afferent pathways in the cat. In: Integrative Control Functions of the Brain, edited by M. Ito. Amsterdam: Elsevier/North‐Holland, 1980.
 453. Monteau, R., and, G. Hilaire. Modifications d'activité des motoneurones laryngés lors de l'installation de la polypnée thermique. J. Physiol. Paris 68: 331–342, 1974.
 454. Moore, G. P., J. P. Segundo, D. H. Perkel, and, H. Levitan. Statistical signs of synaptic interactions in neurons. Biophys. J. 10: 876–900, 1970.
 455. Murakami, Y., and J. A. Kirchner. Respiratory activity of the external laryngeal muscles: an electromyographic study in the cat. In: Ventilatory and Phonatory Control Systems, edited by B. Wyke. London: Oxford Univ. Press, 1973, p. 430–448.
 456. Nathan, M. A., and D. J. Reis. Chronic labile hypertension produced by lesions of nucleus tractus solitarius in the cat. Circ. Res. 40: 72–81, 1977.
 457. Neil, E., and R. G. O'Regan. The effects of electrical stimulation of the distal end of the cut sinus and aortic nerves on peripheral arterial chemoreceptor activity in the cat. J. Physiol. London 215: 15–32, 1971.
 458. Nelson, J. R. Single unit activity in medullary respiratory centers of cat. J. Neurophysiol. 22: 590–598, 1959.
 459. Nesland, R. S., and, F. Plum. Subtypes of medullary respiratory neurons. Exp. Neurol. 12: 337–348, 1965.
 460. Netick, A., A. S. Foutz, and W. C. Dement. Sleep state effects upon respiration following vagotomy and cord transections in the cat. Soc. Neurosci. Abstr. 3: 407 1977.
 461. Netick, A., and, J. Orem. Erroneous classification of neuronal activity by the respiratory modulation index. Neurosci. Lett. 21: 301–306, 1981.
 462. Newsom Davis, J. N., and, F. Plum. Separation of descending spinal pathways to respiratory motoneurons. Exp. Neurol. 34: 78–94, 1972.
 463. Newsom Davis, J. N., and T. A. Sears. The proprioceptive reflex control of the intercostal muscles during their voluntary activation. J. Physiol. London 209: 711–738, 1970.
 464. Newsom Davis, J. N., and, D. Stagg. Interrelationships of the volume and time components of individual breaths in resting man. J. Physiol. London 245: 481–498, 1975.
 465. Ngai, S. H., and S. C. Wang. Organization of central respiratory mechanisms in the brain stem of the cat: localization by stimulation and destruction. Am. J. Physiol. 190: 343–349, 1957.
 466. Nomura, S., N. Mizuno, K. Itoh, K. Matsuda, T. Sugimoto, and, Y. Nakamura. Localization of parabrachial neurons projecting to the thalamus or the amygdala in the cat using horseradish peroxidase. Exp. Neurol. 64: 375–385, 1979.
 467. Norgren, R. Taste pathways to hypothalamus and amygdala. J. Comp. Neurol. 166: 17–30, 1976.
 468. Norgren, R. Projections from the nucleus of the solitary tract in the rat. Neuroscience 3: 207–218, 1978.
 469. Nye, P. C. G., M. A. Hanson, and R. W. Torrance. The effect on breathing of abruptly stopping carotid body discharge. Respir. Physiol. 46: 309–326, 1981.
 470. Nye, P. C. G., and, J. Marsh. Ventilation and carotid chemoreceptor discharge during venous CO2 loading via the gut. Respir. Physiol. 50: 335–350, 1982.
 471. Oberholzer, R. J. H., and W. O. Tofani. The neural control of respiration. In: Handbook of Physiology. Neurophysiology, edited by H. W. Magoun. Washington, DC: Am. Physiol. Soc., 1960, sect. 1, vol. II, chapt. 43, p. 1111–1129.
 472. O'Regan, R. G. Responses of carotid body chemosensory activity and blood flow to stimulation of sympathetic nerves in the cat. J. Physiol. London 315: 81–98, 1981.
 473. O'Regan, R. G., and, S. Majcherczyk. Role of peripheral chemoreceptors and central chemosensitivity in the regulation of respiration and circulation. J. Exp. Biol. 100: 15 1982.
 474. Orem, J. Medullary respiratory neuron activity: relationship to tonic and phasic REM sleep. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 48: 54–65, 1980.
 475. Orem, J. Neuronal mechanisms of respiration in REM sleep. Sleep 3: 251–267, 1980.
 476. Orem, J., and W. C. Dement. Neurophysiological substrates of the changes in respiration during sleep. In: Advances in Sleep Research, edited by E. D. Weitzman. New York: Halsted, 1975, vol. 2, chapt. 1, p. 1–42.
 477. Orem, J., and, T. Dick. Consistency and signal strength of respiratory neuronal activity. J. Neurophysiol. 50: 1098–1107, 1983.
 478. Orem, J., T. Dick, and, P. Norris. Laryngeal and diphragmatic responses to airway occusion in sleep. Electroencephalogr. Clin. Neurophysiol. 50: 151–164, 1980.
 479. Orem, J., and, R. Lydic. Upper airway function during sleep and wakefulness: experimental studies on normal and anesthetized cats. Sleep 1: 49–68, 1978.
 480. Orem, J., R. Lydic, and, P. Norris. Experimental control of the diaphragm and laryngeal abductor muscles by brain stem arousal systems. Respir. Physiol. 38: 203–221, 1979.
 481. Orem, J., J. Montplaisir, and, W. Dement. Changes in the activity of respiratory neurons during sleep. Brain Res. 82: 309–315, 1974.
 482. Orem, J., and, A. Netick. Characteristics of midbrain respiratory neurons in sleep and wakefulness in the cat. Brain Res. 244: 231–241, 1982.
 483. Orem, J., A. Netick, and W. C. Dement. Breathing during sleep and wakefulness in the cat. Respir. Physiol. 30: 265–289, 1977.
 484. Orem, J., A. Netick, and W. C. Dement. Increased upper airway resistance to breathing during sleep in the cat. Electroencephalogr. Clin. Neurophysiol. 43: 14–22, 1977.
 485. Ottersen, O. P., and, Y. Ben‐Ari. Pontine and mesencephalic afferents to the central nucleus of the amygdala of the rat. Neurosci. Lett. 8: 329–334, 1978.
 486. Pack, A. I. Sensory inputs to the medulla. Annu. Rev. Physiol. 43: 73–90, 1981.
 487. Pack, A. I., R. G. Delaney, and A. P. Fishman. Augmentation of phrenic neural activity by increased rates of lung inflation. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 50: 149–161, 1981.
 488. Pack, A. I., M. Ogilvie, R. G. Delaney, and D. J. Murray‐Smith. Action of positive feedback related to lung inflation in the control of ventilation. Comput. Biomed. Res. 15: 503–518, 1982.
 489. Paintal, A. S. Vagal sensory receptors and their reflex effects. Physiol. Rev. 53: 159–227, 1973.
 490. Pappenheimer, J. R., V. Fencl, S. R. Heisey, and, D. Held. Role of cerebral fluids in control of respiration as studied in unanesthetized goats. Am. J. Physiol. 208: 436–450, 1965.
 491. Parmeggiani, P. L. Integrative aspects of hypothalamic influences on respiratory brain stem mechanisms during wakefulness and sleep. In: Central Nervous Control Mechanisms in Breathing, edited by C. von Euler and H. Lagercrantz. New York: Pergamon, 1979, p. 53–69.
 492. Parmeggiani, P. L., and, C. Rabini. Shivering and panting during sleep. Brain Res. 6: 789–791, 1967.
 493. Parmeggiani, P. L., and, C. Rabini. Sleep and environmental temperature. Arch. Ital. Biol. 108: 369–387, 1970.
 494. Parmeggiani, P. L., and, L. Sabbattini. Electromyographic aspects of postural, respiratory and thermoregulatory mechanisms in sleeping cats. Electroencephalogr. Clin. Neurophysiol. 33: 1–13, 1972.
 495. Parrott, A., J. Ponte, M. J. Purves, and, T. Stephenson. Changes in carbon dioxide and pH in pulmonary post‐capillary blood in cats. J. Physiol. London 296: 23P–24P, 1979.
 496. Pasaro, R., S. Gonzalez‐Baron, and J. M. Delgado‐Garcia. Differential localization of laryngeal motoneurons within the nucleus ambiguus of the cat. Neurosci. Lett. Suppl. 10: S373–S374, 1982.
 497. Pearson, K. G. Nerve cells without action potentials. In: Simpler Networks and Behavior, edited by J. C. Fentress. Sunderland, MA: Sinauer, 1976, p. 99–110.
 498. Perkel, D. H., G. L. Gerstein, and G. P. Moore. Neuronal spike trains and stochastic point processes. II. Simultaneous spike trains. Biophys. J. 7: 419–440, 1967.
 499. Perkel, D. H., and, B. Mulloney. Motor pattern production in reciprocally inhibitory neurons exhibiting postinhibitory rebound. Science 185: 181–183, 1974.
 500. Perkins, J. F., Jr. Historical development of respiratory physiology. In: Handbook of Physiology. Respiration, edited by W. O. Fenn and H. Rahn. Washington, DC: Am. Physiol. Soc., 1964, sect. 3, vol. 1, chapt. 1, p. 1–62.
 501. Petrillo, G. A., and, L. Glass. A theory for phase locking of respiration in cats to a mechanical ventilator. Am. J. Physiol. 246 (Regulatory Integrative Comp. Physiol. 15): R311–R320, 1984.
 502. Petrillo, G. A., L. Glass, and, T. Trippenbach. Phase locking of the respiratory rhythm in cats to a mechanical ventilator. Can. J. Physiol. Pharmacol. 61: 599–607, 1983.
 503. Phillipson, E. A. Control of breathing during sleep. Am. Rev. Respir. Dis. 118: 909–939, 1978.
 504. Phillipson, E. A., G. Bowes, E. R. Townsend, J. Duffin, and J. D. Cooper. Role of metabolic CO2 production in ventilatory response to steady state exercise. J. Clin. Invest. 68: 768–774, 1981.
 505. Phillipson, E. A., J. Duffin, and J. D. Cooper. Critical dependence of respiratory rhythmicity on metabolic CO2 load. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 50: 45–54, 1981.
 506. Phillipson, E. A., P. A. McClean, C. E. Sullivan, and, N. Zamel. Interaction of metabolic and behavioral respiratory control during hypercapnia and speech. Am. Rev. Respir. Dis. 117: 903–909, 1978.
 507. Phillipson, E. A., E. Murphy, and L. F. Kozar. Regulation of respiration in sleeping dogs. J. Appl. Physiol. 40: 688–693, 1976.
 508. Pinsker, H. M., and, J. Ayers. Neuronal oscillators. In: The Clinical Neurosciences. Neurology, edited by W. D. Willis. New York: Churchill Livingstone, 1983, p. 203–265.
 509. Pitts, R. F. The respiratory center and its descending pathways. J. Comp. Neurol. 72: 605–625, 1940.
 510. Pitts, R. F. Organization of the respiratory center. Physiol. Rev. 26: 609–630, 1946.
 511. Pitts, R. F., H. W. Magoun, and S. W. Ranson. Interrelations of the respiratory centers in the cat. Am. J. Physiol. 126: 689–707, 1939.
 512. Pitts, R. F., H. W. Magoun, and S. W. Ranson. The origin of respiratory rhythmicity. Am. J. Physiol. 127: 654–670, 1939.
 513. Plum, F., and R. J. Leigh. Abnormalities of central mechanisms. In: Lung Biology in Health and Disease. Regulation of Breathing, edited by T. F. Hornbein. New York: Dekker, 1981, vol. 17, pt. 2, chapt. 16, p. 989–1067.
 514. Pokorski, M. Neurophysiological studies on central chemosensor in medullary ventrolateral areas. Am. J. Physiol. 230: 1288–1295, 1976.
 515. Ponte, J., and M. J. Purves. Frequency response of carotid body chemoreceptors in the cat to changes of PaCO2, PaO2 and pHa. J. Appl. Physiol. 37: 635–647, 1974.
 516. Porter, W. T. The path of the respiratory impulse from the bulb to the phrenic nuclei. J. Physiol. London 17: 455–485, 1895.
 517. Price, J. L., and D. G. Amaral. An autoradiographic study of the projections of the central nucleus of the monkey amygdala. J. Neurosci. 1: 1242–1259, 1981.
 518. Proctor, D. F. Breathing, Speech and Song. New York: Springer‐Verlag, 1980.
 519. Ramón y Cajal, S. Histologie due système nerveux de l'homme et des vertèbres. Paris: Maloine, 1909.
 520. Ranck, J. B. Jr. Which elements are excited in electrical stimulation of mammalian central nervous system: a review. Brain Res. 98: 417–440, 1975.
 521. Rebuck, A. S., and A. S. Slutsky. A clinical method for assessing the ventilatory response to hypoxia. Am. Rev. Respir. Dis. 109: 345–350, 1974.
 522. Rebuck, A. S., and A. S. Slutsky. Measurement of ventilatory responses to hypercapnia and hypoxia. In: Lung Biology in Health and Disease. Regulation of Breathing, edited by T. F. Hornbein. New York: Dekker, 1981, vol. 17, pt. 2, chapt. 1, p. 745–772.
 523. Remmers, J. E. Inhibition of inspiratory activity by intercostal muscle afferents. Respir. Physiol. 10: 358–383, 1970.
 524. Remmers, J. E. Extra‐segmental reflexes derived from intercostal afferents: phrenic and laryngeal responses. J. Physiol. London 233: 45–62, 1973.
 525. Remmers, J. E. Control of breathing during sleep. In: Lung Biology in Health and Disease. Regulation of Breathing, edited by T. F. Hornbein. New York: Dekker, 1981, vol. 17, pt. 2, chapt. 20, p. 1197–1250.
 526. Remmers, J. E., and D. Bartlett Jr.. Reflex control of expiratory airflow and duration. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 42: 80–87, 1977.
 527. Remmers, J. E., D. Bartlett, Jr, and M. D. Putman. Changes in the respiratory cycle associated with sleep. Respir. Physiol. 28: 227–238, 1976.
 528. Remmers, J. E., W. J. de Groot, E. K. Sauerland, and A. M. Anch. Pathogenesis of upper airway occlusion during sleep. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 44: 931–938, 1978.
 529. Remmers, J. E., and, I. Marttila. Action of intercostal muscle afferents on the respiratory rhythm of anesthetized cats. Respir. Physiol. 24: 31–41, 1975.
 530. Remmers, J. E., and W. G. Tsiaris. Effect of lateral cervical cord lesions on the respiratory rhythm of anesthetized, decerebrate cats after vagotomy. J. Physiol. London 233: 63–74, 1973.
 531. Reynolds, L. B. Jr.. Characteristics of an inspiration‐augmenting reflex in anesthetized cats. J. Appl. Physiol. 17: 683–688, 1962.
 532. Ricardo, J. A., and E. T. Koh. Anatomical evidence of direct projections from the nucleus of the solitary tract to the hypothalamus, amygdala, and other forebrain structures in the rat. Brain Res. 153: 1–26, 1978.
 533. Richardson, C. A., D. A. Herbert, and R. A. Mitchell. Modulation of pulmonary stretch receptors and airway resistance by parasympathetic afferents. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 57: 1842–1849, 1984.
 534. Richardson, C. A., and R. A. Mitchell. Power spectral analysis of inspiratory nerve activity in the decerebrate cat. Brain Res. 233: 317–336, 1982.
 535. Riche, D., M. Denavit‐Saubié, and, J. Champagnat. Pontine afferents to the medullary‐respiratory system: anatomo‐functional correlation. Neurosci. Lett. 13: 151–155, 1979.
 536. Richter, D. W. Generation and maintenance of the respiratory rhythm. J. Exp. Biol. 100: 93–107, 1982.
 537. Richter, D. W., and, D. Ballantyne. A three phase theory about the basic respiratory pattern generator. In: Central Neurone Environment and the Control Systems of Breathing and Circulation, edited by M. E. Schläfke, H. P. Koepchen, and W. R. See. Berlin: Springer‐Verlag, 1983, p. 164–174.
 538. Richter, D. W., H. Camerer, M. Meesmann, and, N. Rohrig. Studies on the synaptic interconnection between bulbar respiratory neurones of cats. Pfluegers Arch. 380: 245–257, 1979.
 539. Richter, D. W., H. Camerer, and, U. Sonnhof. Changes in extracellular potassium during the spontaneous activity of medullary respiratory neurons. Pfluegers Arch. 376: 139–149, 1978.
 540. Richter, D. W., and, F. Heyde. Accommodative reactions of medullary respiratory neurons of the cat. J. Neurophysiol. 38: 1172–1180, 1975.
 541. Richter, D. W., F. Heyde, and, M. Gabriel. Intracellular recordings from different types of medullary respiratory neurons of the cat. J. Neurophysiol. 38: 1162–1171, 1975.
 542. Richter, D. W., K. M. Spyer, and, P. Langhorst. The Role of the Nuclei Tractus Solitarii in the Central Regulation of the Respiratory and Cardiovascular Systems, Heidelberg, West Germany: Univ. of Heidelberg Press, 1980.
 543. Riddle, W., and, M. Younes. A model for the relation between respiratory neural and mechanical outputs. II. Methods. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 51: 979–989, 1981.
 544. Rijlant, P. Localisation of the respiratory centre. J. Physiol. London 90: 43P–45P, 1937.
 545. Rikard‐Bell, G. C., and E. K. Bystrzycka. Localization of phrenic motor nucleus in the cat and rabbit studied with horseradish peroxidase. Brain Res. 194: 479–483, 1980.
 546. Rikard‐Bell, G. C., E. K. Bystrzycka, and B. S. Nail. Brainstem projections to the phrenic nucleus: an HRP study in the cat. Neurosci. Lett. Suppl. 11: S70, 1982.
 547. Riley, D. A., and A. J. Berger. A regional histochemical and electromyographic analysis of the cat respiratory diaphragm. Exp. Neurol. 66: 636–649, 1979.
 548. Rosenbaum, H., and, B. Renshaw. Descending respiratory pathways in the cervical spinal cord. Am. J. Physiol. 157: 468–476, 1949.
 549. Rubio, J. E. A mathematical model of the respiratory center. Bull. Math. Biophys. 29: 719–736, 1967.
 550. Rubio, J. E. A new mathematical model of the respiratory center. Bull. Math. Biophys. 34: 467–481, 1972.
 551. Russell, D. F., and D. K. Hartline. Slow active potentials and bursting motor patterns in pyloric network of the lobster, Panulirus interruptus. J. Neurophysiol. 48: 914–937, 1982.
 552. St. John, W. M. Respiratory tidal volume responses of cats with chronic pneumotaxic center lesions. Respir. Physiol. 16: 92–108, 1972.
 553. St. John, W. M. Central nervous system regulation of ventilation. In: Regulation of Ventilation and Gas Exchange, edited by D. G. Davies and C. D. Barnes. New York: Academic, 1978, p. 1–32.
 554. St. John, W. M. Respiratory neuron responses to hypercapnia and carotid chemoreceptor stimulation. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 51: 816–822, 1981.
 555. St. John, W. M. Independent, bilateral sites for ventilatory neurogenesis. In: Central Neural Production of Periodic Respiratory Movements, edited by J. L. Feldman and A. J. Berger. Evanston, IL: Northwestern Univ. Press, 1982, p. 167–168.
 556. St. John, W. M., and A. L. Bianchi. Comparison of activities of medullary respiratory neurons in eupnea and apneusis. Resp. Physiol. 51: 361–377, 1983.
 557. St. John, W. M., and D. Bartlett Jr.. Comparison of phrenic motoneuron responses to hypercapnea and isocapnic hypoxia. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 46: 1096–1102, 1979.
 558. St. John, W. M., and D. Bartlett Jr.. Comparison of phrenic motoneuron activity during eupnea and gasping. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 50: 994–998, 1981.
 559. St. John, W. M., D. Bartlett, Jr., K. V. Knuth, and J.‐C. Hwang. Brain stem genesis of automatic ventilatory patterns independent of spinal mechanisms. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 51: 204–210, 1981.
 560. St. John, W. M., and, A. Daubenspeck. Regulation of ventilatory responses in vagotomized cats by caudal brainstem sites. Respir. Physiol. 36: 187–199, 1979.
 561. St. John, W. M., R. L. Glasser, and R. A. King. Apneustic breathing after vagotomy in cats with chronic pneumotaxic center lesions. Respir. Physiol. 12: 239–250, 1971.
 562. St. John, W. M., and D. V. Knuth. A characterization of the respiratory pattern of gasping. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 50: 984–993, 1981.
 563. St. John, W. M., and S. C. Wang. Alteration from apneusis to more regular rhythmic respiration in decerebrate cats. Respir. Physiol.: 31: 91–106, 1977.
 564. St. John, W. M., and S. C. Wang. Response of medullary respiratory neurons to hypercapnia and isocapnic hypoxia. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 43: 812–821, 1977.
 565. Salmoiraghi, G. C. Functional organization of brain stem respiratory neurones. Ann. NY Acad. Sci. 109: 571–582, 1963.
 566. Salmoiraghi, G. C., and R. von Baumgarten. Intracellular potentials from respiratory neurons in brain‐stem of cat and mechanism of rhythmic respiration. J. Neurophysiol. 24: 203–218, 1961.
 567. Salmoiraghi, G. C., and B. D. Burns. Localization and patterns of discharge of respiratory neurons in brain‐stem of cat. J. Neurophysiol. 23: 2–13, 1960.
 568. Salmoiraghi, G. C., and B. D. Burns. Notes on mechanism of rythmic respiration. J. Neurophysiol. 23: 14–26, 1960.
 569. Sant'Ambrogio, G. Information arising from the tracheobronchial tree of mammals. Physiol. Rev. 62: 531–569, 1982.
 570. Saper, C. B., and A. D. Loewy. Efferent connections of the parabrachial nucleus in the rat. Brain Res. 197: 291–317, 1980.
 571. Saper, C. B., A. D. Loewy, L. W. Swanson, and W. M. Cowan. Direct hypothalamo‐autonomic connections. Brain Res. 117: 305–312, 1976.
 572. Schlaefke, M. E. Central chemosensitivity: a respiratory drive. Rev. Physiol. Biochem. Pharmacol. 90: 171–244, 1981.
 573. Schlaefke, M. E., J. F. Kille, and H. H. Loeschcke. Elimination of central chemosensitivity by coagulation of a bilateral area on the ventral medullary surface in awake cats. Pfluegers Arch. 378: 231–241, 1979.
 574. Schlaefke, M. E., H. P. Koepchen, and W. R. See. (editors). Central Neurone Environment and the Control Systems of Breathing and Circulation. New York: Springer‐Verlag, 1982.
 575. Schlaefke, M. E., W. R. See, A. Herker‐See, and H. H. Loeschcke. Respiratory response to hypoxia and hypercapnia after elimination of central chemosensitivity. Pfluegers Arch. 381: 241–248, 1979.
 576. Schwanghart, F., R. Schroter, D. Klussendorf, and H. P. Koepchen. The influence of novocaine block of superficial brain stem structures on respiratory and reticular neurons. In: Central Rhythmic and Regulation, edited by W. Umbach and H. P. Koepchen. Stuttgart, West Germany: Hippokrates, 1974, p. 104–110.
 577. Sears, T. A. Activity of fusimotor fibers innervating muscle spindles in the intercostal muscles of the cat. Nature London 197: 1013–1014, 1963.
 578. Sears, T. A. Efferent discharges in alpha and fusimotor fibres of intercostal nerves of the cat. J. Physiol. London 174: 295–315, 1964.
 579. Sears, T. A. Some properties and reflex connexions of respiratory motoneurons of the cat's thoracic spinal cord. J. Physiol. London 175: 386–403, 1964.
 580. Sears, T. A. The slow potentials of thoracic respiratory motoneurones and their relation to breathing. J. Physiol. London 175: 404–442, 1964.
 581. Sears, T. A. The respiratory motoneurone: integration at spinal segmental level. In: Breathlessness, edited by J. B. Howell and E. M. Campbell. Oxford, UK: Blackwell, 1966, p. 33–47.
 582. Sears, T. A. Breathing: a sensori‐motor act. Sci. Basis Med. Annu. Rev. p. 128–147, 1971.
 583. Sears, T. A. Servo control of the intercostal muscles. In: New Developments in EMG and Clinical Neurophysiology, edited by J. E. Desmedt. Basel: Karger, 1973, p. 404–417.
 584. Sears, T. A. Central pathways mediating muscular patterns of activity in respiration. In: Central Production of Periodic Respiratory Movements, edited by J. L. Feldman and A. J. Berger. Evanston, IL: Northwestern Univ. Press, 1982, p. 35–37.
 585. Sears, T. A., A. J. Berger, and E. A. Phillipson. Reciprocal tonic activation of inspiratory and expiratory motoneurones by chemical drives. Nature London 299: 728–730, 1982.
 586. Sears, T. A., and J. N. Davis. The control of respiratory muscles during voluntary breathing. Ann. NY Acad. Sci. 155: 183–190, 1968.
 587. Sears, T.A., and D. Stagg. Short‐term synchronization of intercostal motoneurone activity. J. Physiol. London 263: 357–381, 1976.
 588. See, W. R., M. E. Schlaefke, and H. H. Loeschcke. Role of chemical afferents in the maintenance of rhythmic respiratory movements. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 54: 453–459, 1983.
 589. Segers, L. S., R. Shannon, and R. G. Lindsey. Short time correlations between respiratory neurons in cat brainstem. Soc. Neurosci. Abstr. 8: 559 1982.
 590. Selverston, A. I. Are central pattern generators understandable? Behav. Brain Sci. 3: 535–571, 1980.
 591. Selverston, A. I., and J. P. Miller. Mechanisms underlying pattern generation in lobster stomatogastric ganglion as determined by selective inactivation of identified neurons. I. Pyloric system. J. Neurophysiol. 44: 1102–1121, 1980.
 592. Sessle, B. J., F. Greenwood, J. P. Lund, and G. E. Lucier. Effects of upper respiratory tract stimuli on respiration and single respiratory neurons in the adult cat. Exp. Neurol. 61: 245–259, 1978.
 593. Shannon, R. Respiratory frequency control during external elastic loading and chest compression. Respir. Physiol. 23: 11–22, 1975.
 594. Shannon, R. Effects of thoracic dorsal rhizotomies on the respiratory pattern in anesthetized cats. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 43: 20–26, 1977.
 595. Shannon, R. Involvement of thoracic nerve afferents in the respiratory response to chest compression. Respir. Physiol. 36: 65–76, 1979.
 596. Shannon, R. Intercostal and abdominal muscle afferent influence on medullary dorsal respiratory group neurons. Respir. Physiol. 39: 73–94, 1980.
 597. Shannon, R. Reflexes from respiratory muscles and costovertebral joints. In: Handbook of Physiology. The Respiratory System. Control of Breathing, edited by N. S. Cherniack and J. G. Widdicombe. Bethesda, MD: Am. Physiol. Soc., 1986, sect. 3, vol. II, chapt. 13, p. 431–447.
 598. Shannon, R., and, D. Freeman. Nucleus retroambigualis respiratory neurons: responses to intercostal and abdominal muscle afferents. Respir. Physiol. 45: 357–375, 1981.
 599. Shannon, R., and B. G. Lindsey. Intercostal and abdominal muscle afferent influence on pneumotaxic center respiratory neurons. Respir. Physiol. 52: 85–98, 1983.
 600. Shannon, R., S. Saporta, and B. G. Lindsey. Transmission of proprioceptor afferent information to medullary respiratory areas. Exp. Neurol. 78: 222–225, 1982.
 601. Sherry, J. H., and, D. Megirian. Analysis of the respiratory role of intrinsic laryngeal motoneurons of the cat. Exp. Neurol. 49: 456–465, 1975.
 602. Sherry, J. H., and, D. Megirian. State dependence of upper airway respiratory motoneurons: functions of the cricothyroid and nasolabial muscle of the unanesthetized rat. Electroencephalogr. Clin. Neurophysiol. 43: 218–228, 1977.
 603. Sieck, G. C., M. Fournier, and M. J. Belman. Physiological properties of motor units in the diaphragm. In: Neurogenesis of Central Respiratory Rhythm: Electrophysiological, Pharmacological and Clinical Aspects, edited by A. L. Bianchi and M. Denavit‐Saubié. Lancaster, UK: MTP, 1985, p. 227–229.
 604. Sieck, G. C., and R. M. Harper. Pneumotaxic area neuronal discharge during sleep‐waking states in the cat. Exp. Neurol. 67: 79–102, 1980.
 605. Sieck, G. C., R. B. Trelease, and R. M. Harper. Activity of single diaphragmatic muscle units during sleep‐waking states in the cat. Sleep Res. 10: 40 1981.
 606. Sieck, G. C., R. B. Trelease, and R. M. Harper. Discharge of diaphragm motor units during sleep. Soc. Neurosci. Abstr. 8: 559 1982.
 607. Simmers, A. J., and B. M. H. Bush. Non‐spiking neurones controlling ventilation in crabs. Brain Res. 197: 247–252, 1980.
 608. Simmers, A. J., and B. M. H. Bush. Central nervous mechanisms controlling rhythmic burst generation in the ventilatory motoneurones of Carcinus maenas. J. Comp. Physiol. 150: 1–21, 1983.
 609. Sobotta, J. Atlas of Human Anatomy. Munich, West Germany: Urban & Schwarzenberg, 1974.
 610. Sommer, D., J. L. Feldman, and M. I. Cohen. Responses of caudal medullary expiratory neurons to lung inflation. Federation Proc. 38: 1144 1979.
 611. Speck, D. F., and J. L. Feldman. The effects of micro‐stimulation and microlesions in the ventral and dorsal respiratory groups in medulla of cat. J. Neurosci. 2: 744–757, 1982.
 612. Speck, D. F., and C. L. Webber Jr.. Time course of intercostal afferent termination of inspiration. Respir. Physiol. 43: 133–145, 1981.
 613. Spyer, K. M. Neural organization and control of the baroreceptor reflex. Rev. Physiol. Biochem. Pharmacol. 88: 24–124, 1981.
 614. Stella, G. On the mechanism of production, and the physiological significance of “apneusis.” J. Physiol. London 93: 10–23, 1938.
 615. Sullivan, C. E. Breathing in sleep. Physiology in sleep research. In: Topics in Physiology, edited by J. Orem and C. D. Barnes. New York: Academic, 1980, p. 213–279.
 616. Sullivan, C. E., L. F. Kozar, E. Murphy, and E. A. Phillipson. Primary role of respiratory afferents in sustaining breathing rhythm. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 45: 11–17, 1978.
 617. Suzue, T. Respiratory rhythm generation in the in vitro brain stem‐spinal cord preparation of the neonatal rat. J. Physiol. London 354: 173–183, 1984.
 618. Szentagothai, J. Die Lokalisation der Kehlkopfmuskulatur in den Vaguskerernen. Z. Anat. Entwicklungsgesch. 112: 704–710, 1943.
 619. Taber, E. The cytoarchitecture of the brainstem of the cat. Brain stem nuclei of cat. J. Comp. Neurol. 116: 27–52, 1961.
 620. Takeuchi, Y., J. H. McLean, and D. A. Hopkins. Reciprocal connections between the amygdala and parabrachial nuclei: ultrastructural demonstration by degeneration and axonal transport of horseradish peroxidase in the cat. Brain. Res. 239: 583–588, 1982.
 621. Tang, P. C. Localization of the pneumotaxic center in the cat. Am. J. Physiol. 172: 645–652, 1953.
 622. Tang, P. C. Brain stem control of respiratory depth and rate in the cat. Respir. Physiol. 3: 349–366, 1967.
 623. Taylor, E. K., J. Duffin, B. R. Vachon, and D. H. McCracken. The recruitment times and firing patterns of the medullary respiratory neurones of the cat. Respir. Physiol. 34: 247–266, 1978.
 624. Tenney, S. M., and D. Bartlett Jr.. Some comparative aspects of the control of breathing. In: Lung Biology in Health and Disease. Regulation of Breathing, edited by T. F. Hornbein. New York: Dekker, 1981, vol. 17, pt. 1, chapt. 2, p. 67–102.
 625. Tibes, U. Reflex inputs to the cardiovascular and respiratory centers from dynamically working canine muscles. Circ. Res. 41: 332–341, 1977.
 626. Torvik, A. The spinal projection from the nucleus of the solitary tract. An experimental study in the cat. J. Anat. 91: 314–322, 1957.
 627. Trippenbach, T. Effects of drugs on the respiratory control system in the perinatal period and during postnatal development. Pharmacol. Ther. 20: 307–340, 1983.
 628. Trippenbach, T., G. Kelly, and, D. Marlot. Respiratory effects of stimulation of intercostal muscles and saphenous nerve in kittens. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 54: 1736–1744, 1983.
 629. Trouth, C. O., H. H. Loeschcke, and, J. Berndt. A superficial substrate on the ventral surface of the medulla oblongata influencing respiration. Pfluegers Arch. 339: 135–152, 1973.
 630. Trouth, C. O., H. H. Loeschcke, and, J. Berndt. Histological structures in the chemosensitive regions on the ventral surface of the cat's medulla oblongata. Pfluegers Arch. 339: 171–183, 1973.
 631. Trouth, C. O., M. Odek‐Ogunde, and J. A. Holloway. Morphological observations on superficial medullary CO2‐chemosensitive areas. Brain Res. 246: 35–45, 1982.
 632. Trouth, C. O., J. W. Patrickson, J. A. Holloway, and L. E. Wright. Neurophysiological studies on superficial medullary chemosensitive area for respiration. Brain Res. 246: 47–56, 1982.
 633. Vachon, B. R., and, J. Duffin. Cross‐correlation of medullary respiratory neurons in the cat. Exp. Neurol. 61: 15–30, 1978.
 634. Viala, D., and, E. Freton. Evidence for respiratory and locomotor pattern generators in the rabbit cervico‐thoracic cord and for their interactions. Exp. Brain Res. 49: 247–256, 1983.
 635. Viala, D., C. Vidal, and, E. Freton. Coordinated rhythmic bursting in respiratory and locomotor muscle nerves in the spinal rabbit. Neurosci. Lett. 11: 155–159, 1979.
 636. Vibert, J. F., F. Bertrand, M. Denavit‐Saubié, and, A. Hugelin. Discharge patterns of bulbo‐pontine respiratory unit populations in cat. Brain Res. 114: 211–225, 1976.
 637. Vibert, J. F., F. Bertrand, M. Denavit‐Saubié, and, A. Hugelin. Three dimensional representation of bulbo‐pontine respiratory networks architecture from unit density maps. Brain Res. 114: 227–244, 1976.
 638. Vidruk, E. H., and J. A. Dempsey. Carotid body chemoreceptor activity as recorded from the petrosal ganglion in cats. Brain Res. 181: 455–459, 1980.
 639. Waldron, I. Activity patterns in respiratory muscles and in respiratory neurones of the rostral medulla of the cat. J. Physiol. London 208: 373–383, 1970.
 640. Walker, J. L.Jr., and A. M. Brown. Unified account of variable effects of carbon dioxide on nerve cells. Science 167: 1502–1504, 1970.
 641. Wamsley, J. K., M. S. Lewis, W. S. Young, and M. J. Kuhar. Autoradioraphic localization of muscarinic cholinergic receptors in rat brainstem. J. Neurosci. 1: 176–191, 1981.
 642. Wang, S. C., and S. H. Ngai. General organization of central respiratory mechanisms. In: Handbook of Physiology. Respiration, edited by W. O. Fenn and H. Rahn. Washington, DC: Am. Physiol. Soc, 1964, sect. 3, vol. 1, chapt. 19, p. 487–505.
 643. Wang, S. C., S. H. Ngai, and M. J. Frumin. Organization of central respiratory mechanisms in the brain stem of the cat: genesis of normal respiratory rhythmicity. Am. J. Physiol. 190: 333–342, 1957.
 644. Webber, C. L.Jr., and C. N. Peiss. Structural and functional characteristics of individual phrenic motoneurons. Pfluegers Arch. 364: 113–121, 1976.
 645. Webber, C. L.Jr., and C. N. Peiss. Pentobarbital‐induced apneusis in intact, vagotomized, and pneumotaxic‐lesioned cats. Respir. Physiol. 38: 37–57, 1979.
 646. Webber, C. L.Jr., and, K. Pleschka. Central respiratory drive potentials and membrane potential trajectories in phrenic motoneurons. Brain Res. 211: 179–184, 1981.
 647. Webber, C. L.Jr., R. D. Wurster, and J. M. Chung. Cat phrenic nucleus architecture as revealed by horseradish peroxidase mapping. Exp. Brain Res. 35: 395–406, 1979.
 648. Wertheimer, E. Sur les modifications de la respiration produites par les injection intraveineuses de sonde chez les animaux as moelle cervicale sechonée. C.R. Soc. Biol. 59: 668–669, 1905.
 649. Whipp, B. J. The control of exercise hyperpnea. In: Lung Biology in Health and Disease. Regulation of Breathing, edited by T. F. Hornbein. New York: Dekker, 1981, vol. 17, pt. 2, chapt. 17, p. 1069–1140.
 650. Whipp, B. J., and S. A. Ward. Cardiopulmonary coupling during exercise. J. Exp. Biol. 100: 175–194, 1982.
 651. Widdicombe, J. G. Defence mechanisms of the respiratory system. Int. Rev. Physiol. 14: 291–315, 1977.
 652. Widdicombe, J. G. Nervous receptors in the respiratory tract and lungs. In: Lung Biology in Health and Disease. Regulation of Breathing, edited by T. F. Hornbein. New York: Dekker, 1981, vol. 17, pt. 1, chapt. 6, p. 429–472.
 653. Winfree, A. T. The Geometry of Biological Time. New York: Springer‐Verlag, 1980.
 654. Wyman, R. J. Neural generation of the breathing rhythm. Annu. Rev. Physiol. 39: 417–448, 1977.
 655. Wyss, O. A. M. Die nervose Steuerung der Atmung. Ergeb. Physiol. Biol. Chem. Exp. Pharmakol. 54: 1–479, 1964.
 656. Yamada, K. A., W. P. Norman, P. Hamosh, and R. A. Gillis. Medullary ventral surface GABA receptors affect respiratory and cardiovascular function. Brain Res. 248: 71–78, 1982.
 657. Yamamoto, W. S. Computer simulation of ventilatory control by both neural and humoral CO2 signals. Am. J. Physiol. 238 (Regulatory Integrative Comp. Physiol. 7): R28–R35, 1980.
 658. Yamamoto, W. S., and M. W. Edwards Jr.. Homeostasis of carbon dioxide during intravenous infusion of carbon dioxide. J. Appl. Physiol. 15: 807–818, 1960.
 659. Younes, M., and, J. Polacheck. Temporal changes in effectiveness of a constant inspiratory‐terminating vagal stimulus. J. Appl. Physiol.: Respirat. Environ. Exercise. Physiol. 50: 1183–1192, 1981.
 660. Younes, M. K., and J. E. Remmers. Control of tidal volume and respiratory frequency. In: Lung Biology in Health and Disease. Regulation of Breathing, edited by T. F. Hornbein. New York: Dekker, 1981, vol. 17, pt. 1, chapt. 9, p. 621–674.
 661. Younes, M. K., J. E. Remmers, and, J. Baker. Characteristics of inspiratory inhibition by phasic volume feedback in cats. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 45: 80–86, 1978.
 662. Younes, M., and, W. Riddle. A model for the relation between respiratory neural and mechanical outputs. I. Theory. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 51: 963–978, 1981.
 663. Younes, M., W. Riddle, and, J. Polacheck. A model for the relation between respiratory neural and mechanical outputs. III. Validation. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 51: 990–1001, 1981.
 664. Zuperku, E. J., F. A. Hopp, and J. P. Kampine. Central integration of pulmonary stretch receptor input in the control of expiration. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 52: 1296–1315, 1982.

Contact Editor

Submit a note to the editor about this article by filling in the form below.

* Required Field

How to Cite

Jack L. Feldman. Neurophysiology of Breathing in Mammals. Compr Physiol 2011, Supplement 4: Handbook of Physiology, The Nervous System, Intrinsic Regulatory Systems of the Brain: 463-524. First published in print 1986. doi: 10.1002/cphy.cp010409