Upper Airway Motor Systems

Bartlett, D.

doi:10.1002/cphy.cp030208

Cited by 48 publications

(44 citation statements)

References 118 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The neural mechanism by which deglutition resets the respiratory oscillator is not known. Deglutition can be induced in animals by electrical stimulation of the anterolateral prefrontal cortex (Sumi, 1969) or by stimulation of superior laryngeal nerve (SLN) afferents (Doty & Bosma, 1956;Miller, 1972), which project to the nucleus tractus solitarii (NTS) and reticular formation (Doty, Richmond & Storey, 1956;Sumi, 1969;Car, 1973). There is evidence that corticofugal and SLN inputs converge on the NTS, which appears to serve as the initial integrative site to potentiate other medullary sites (such as the nucleus ambiguus) involved in the generation of deglutition.…”

Section: Discussionmentioning

confidence: 99%

Respiratory phase resetting and airflow changes induced by swallowing in humans.

Paydarfar

Gilbert

Poppel

et al. 1995

The Journal of Physiology

186

163

View full text Add to dashboard Cite

1. Relationships between the timing of respiration and deglutition were studied in thirty awake healthy subjects at rest. Deglutition was monitored by submental electromyography, pharyngeal manometry and videofluoroscopy. Respiration was recorded by measurement of oronasal airflow and chest wall movement. Three types of deglutition were studied: injected bolus swallows, spontaneous swallows, and visually cued swallows of boluses previously placed in the mouth. 2. The effect of each swallow on respiratory rhythm was characterized by measurement of cophase, defined as the interval between the onset of deglutitive submental EMG activity to the onset of subsequent rescheduled inspirations. Cophase was determined for swallows initiated at different phases of the respiratory cycle. In all subjects deglutition caused phase resetting of respiratory rhythm. Cophase was largest for swallows initiated near the inspiratory-expiratory (I-E) transition and smallest for swallows initiated near the expiratory-inspiratory (E-I) transition. The pattern of respiratory resetting by deglutition was topologically classified as type 0. This pattern was shown for swallows induced by bolus injection or visual cue, and for spontaneous swallows. 3. The incidence of spontaneous deglutition was influenced by the position of the swallow in the respiratory cycle. Few spontaneous swallows were initiated near the E-I transition whereas most occurred from late inspiration to mid-expiration. 4. Deglutition caused an abrupt decrease in airflow leading to an interval of apnoea, followed by a period of expiration. The duration of deglutition apnoea for spontaneous swallows was shorter than that for 5 ml bolus swallows, and was unaffected by the respiratory phase of swallow initiation. The period of expiration after swallowing was longest for swallows initiated at the I-E transition, and shortest for E-I swallows. 5. The intervals between bolus injection and the onset of deglutition apnoea, and the timing of swallowing events, were not significantly altered by the phase in the respiratory cycle at which swallowing was exhibited. 6. To quantify the relationship between bolus flow and respiration, we determined the latencies between cessation of inspiratory airflow and arrival of the bolus at the larynx (a.), and between laryngeal bolus departure and resumption of inspiratory airflow (a). Both values were dependent upon the respiratory phase of swallowing. The lowest values for a and a were found for early-inspiratory and late-expiratory swallows, respectively. 7. We conclude that swallowing causes respiratory phase resetting with a pattern that is characteristic of the strong perturbations of an attractor-cycle oscillator. The threshold for initiation of swallowing in awake subjects is influenced by, but not strongly coupled to, the phase of respiration. We propose that respiratory timing, in addition to anatomical barriers within the upper airway, influences the vulnerability for aspiration during deglutition. Swallows initiated near the E-I transiti...

show abstract

Section: Discussionmentioning

confidence: 99%

Respiratory phase resetting and airflow changes induced by swallowing in humans.

Paydarfar

Gilbert

Poppel

et al. 1995

The Journal of Physiology

186

163

View full text Add to dashboard Cite

show abstract

“…Accordingly, opening or closing of the glottis serves several functions, including respiration, airway protection, and vocalization. In eupnea, the vocal fold is abducted during inspiration to decrease airway resistance and is slightly adducted during expiration, which brakes expiratory airflow and so limits collapse of the lung (Bartlett, 1986). During vocalization, forced expiratory airflow with glottal narrowing vibrates the vocal cords.…”

Section: Abstract: Laryngeal Motoneuron; Vocalization; Coughing; Swamentioning

confidence: 99%

“…Barillot et al (1990) reported that laryngeal motoneurons consist of inspiratory laryngeal motoneurons (ILMs) that depolarize during inspiration and expiratory laryngeal motoneurons (ELMs) that depolarize during expiration. Because the adductor and abductor muscles are activated during the expiratory and inspiratory phases in eupnea, respectively (Wyke and K irchner, 1976;Bartlett, 1986), EL Ms and IL Ms are thought to correspond to the adductor and abductor motoneurons, respectively.…”

Section: Abstract: Laryngeal Motoneuron; Vocalization; Coughing; Swamentioning

confidence: 99%

Multifunctional Laryngeal Motoneurons: an Intracellular Study in the Cat

Shiba¹,

Satoh

Kobayashi

et al. 1999

J. Neurosci.

View full text Add to dashboard Cite

We studied the patterns of membrane potential changes in laryngeal motoneurons (LMs) during vocalization, coughing, swallowing, sneezing, and the aspiration reflex in decerebrate paralyzed cats. LMs, identified by antidromic activation from the recurrent laryngeal nerve, were expiratory (ELMs) or inspiratory (ILMs) cells that depolarized during their respective phases in eupnea. During vocalization, most ELMs depolarized and most ILMs hyperpolarized. Some ILMs depolarized slightly during vocalization. During coughing, ELMs depolarized abruptly at the transition from the inspiratory to the expiratory phase. In one-third of ELMs, this depolarization persisted throughout the abdominal burst. In the remainder ("type A"), it was interrupted by a transient repolarization. ILMs exhibited a membrane potential trajectory opposite to that of type A ELMs during coughing. During swallowing, the membrane potential of ELMs decreased transiently at the onset of the hypoglossal burst and then depolarized strongly during the burst. ILMs hyperpolarized sharply at the onset of the burst and depolarized as hypoglossal activity ceased. During sneezing, ELMs and ILMs exhibited membrane potential changes similar to those of type A ELMs and ILMs during coughing. During the aspiration reflex, ELMs and ILMs exhibited bell-shaped hyperpolarization and depolarization trajectories, respectively. We conclude that central drives to LMs, consisting of complex combinations of excitation and inhibition, vary during vocalization and upper airway defensive reflexes. This study provides data for analysis of the neuronal networks that produce these various behaviors and analysis of network reorganization caused by changes in dynamic connections between the respiratory and nonrespiratory neuronal networks.

show abstract

“…Central respiratory activation of upper airway dilator muscles opposes this airway collapsing effect (Bartlett, 1986). In addition to this NIS 87 13 central mechanism promoting upper airway patency, recent studies have shown that negative pressure applied to the isolated upper airway in anaesthetized animals causes reflex activation of upper airway dilator muscles, particularly the genioglossus (AMathew, Abu-Osba & Thach, 1982 a, b; Lunteren, van de Graaff, Parker, Mitra, Haxhiu, Strohl & Cherniack, 1984).…”

Section: Introductionmentioning

confidence: 99%

Evidence for reflex upper airway dilator muscle activation by sudden negative airway pressure in man.

Horner

Innes

Murphy

et al. 1991

The Journal of Physiology

259

210

View full text Add to dashboard Cite

SUMMARY1. To determine if negative upper airway pressure causes reflex pharyngeal dilator muscle activation, we used intra-oral bipolar surface electrodes to record genioglossus electromyogram (EMG) activity in response to 500 ms duration pressure stimuli of 0. -25.-5.-15, -25 and -35 cmH2O (0-90 % rise time < 30 ms) in ten normal, conscious, supine subjects.2. WN&ith the subjects relaxed at end-expiration, stimuli were applied in each of three conditions: (i) glottis open (GO), (ii) glottis closed (GC) and (iii) controls with the mouth and nose closed.3. Six rectified and integrated EMG responses were bin averaged for each pressure in each experimental condition. Response latency was defined as the time when the EMG activity significantly increased above pre-stimulus levels. Response magnitude was quantified as the ratio of the EMG activity for 80 ms post-stimulus to 80 ms prestimulus; data from after the subject's voluntary reaction time (for tongue protrusion) were not analysed.4. Negative airway pressure activated the genioglossus. The median latency of activation (34 ms) was much faster than the time for voluntary activation (184 ms) indicating a reflex response.5. Significant activation, compared to 0 cmH20 controls and controls with mouth and nose closed, occurred with pressures of at least -5 cmH2O (GC) and -15 cmH2O (GO). , responses with GO were significantly greater than with GC.6. The magnitude ('strength') of the responses differed between subjects; these differences were repeatable.7. WTe conclude that negative airway pressure causes reflex pharyngeal dilator muscle activation in man. Responses with GC suggest that upper airway receptors can mediate the response but larger responses with GO indicate a contribution from subglottal receptors.

show abstract

Upper Airway Motor Systems

Cited by 48 publications

References 118 publications

Respiratory phase resetting and airflow changes induced by swallowing in humans.

Respiratory phase resetting and airflow changes induced by swallowing in humans.

Multifunctional Laryngeal Motoneurons: an Intracellular Study in the Cat

Evidence for reflex upper airway dilator muscle activation by sudden negative airway pressure in man.

Contact Info

Product

Resources

About