Thyroarytenoid muscle activity during wakefulness and sleep in normal adults

To determine the respiratory-related activity of the thyroarytenoid (TA) muscle in normal adults, intramuscular electromyographic recordings were performed in eight normal adult males during wakefulness and sleep. Phasic expiratory TA activity was present during normal tidal breathing in all subjects during wakefulness. Tonic activity was frequently present during inspiration. After an initial rapid rise in activity near the onset of expiration, phasic TA activity generally exhibited one of three different discharge patterns: a plateau, a progressive increase, or, less commonly, a progressive decrease in activity. In four of five subjects examined, peak TA activity during quiet breathing in wakefulness appeared to be directly related to time of expiration. At a particular lung volume above end-expiratory volume during wakefulness, measurements of expiratory resistance were directly related to the level of TA activity. TA activity disappeared during stable periods of non-rapid-eye-movement sleep and exhibited paroxysmal bursts of activity during rapid-eye-movement sleep. The results during wakefulness indicate that the TA contributes to an active adduction of the vocal cords in expiration and suggest the presence of an active laryngeal braking mechanism during exhalation.

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Arytenoideus muscle activity in normal adult humans during wakefulness and sleep

Journal of Applied Physiology ◽

10.1152/jappl.1991.70.4.1655 ◽

1991 ◽

Vol 70 (4) ◽

pp. 1655-1664 ◽

Cited By ~ 22

Author(s):

S. T. Kuna ◽

G. Insalaco ◽

R. D. Villeponteaux

Keyword(s):

Vocal Cord ◽

Eye Movement ◽

Active Role ◽

Rapid Eye Movement ◽

Rapid Eye Movement Sleep ◽

Related Activity ◽

Quiet Breathing ◽

Level Of Activity ◽

Discharge Patterns ◽

Active Phenomenon

The respiratory-related activity of the arytenoideus (AR) muscle, a vocal cord adductor, was investigated in 10 healthy adults during wakefulness and sleep. AR activity was measured with intramuscular hooked-wire electrodes implanted by means of a fiber-optic nasopharyngoscope. Correct placement of the electrodes was confirmed by discharge patterns during voluntary maneuvers. The AR usually exhibited respiratory-related activity during quiet breathing in all awake subjects. Tonic activity was frequently present throughout the respiratory cycle. The pattern of phasic discharge during wakefulness exhibited considerable intrasubject variability both in timing and level of activity. Phasic activity usually began in midinspiration and terminated in mid- to late expiration. Periods of biphasic discharge were observed in four subjects. Phasic discharge primarily confined to expiration was also commonly observed. During quiet breathing in wakefulness, the level of phasic AR activity appeared to be directly related to the time of expiration. The AR was electrically silent in the six subjects who achieved stable periods of non-rapid-eye-movement sleep. Rapid-eye-movement sleep was observed in three subjects and was associated with sporadic paroxysmal bursts of AR activity. The results during wakefulness indicate that vocal cord adduction in expiration is an active phenomenon and suggest that the larynx may have an active role in braking exhalation.

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Coordination between glottic adductor muscle and diaphragm EMG activity in fetal lambs in utero

Journal of Applied Physiology ◽

10.1152/jappl.1998.84.5.1560 ◽

1998 ◽

Vol 84 (5) ◽

pp. 1560-1565 ◽

Cited By ~ 23

Author(s):

Irenej Kianicka ◽

Véronique Diaz ◽

Dominique Dorion ◽

Jean-Paul Praud ◽

Keyword(s):

Eye Movement ◽

Blood Gases ◽

Adductor Muscle ◽

In Utero ◽

Late Gestation ◽

Emg Activity ◽

Rapid Eye Movement ◽

Rapid Eye Movement Sleep ◽

Polygraphic Recordings ◽

Thyroarytenoid Muscle

It has previously been reported that active glottic adduction is present during prolonged apneas but absent during periods of breathing movements in fetal lambs in utero. The present study was aimed at examining the precise coordination between fetal breathing movements [diaphragm electromyographic (EMG) activity (Di EMG)] and glottic adduction [thyroarytenoid muscle EMG activity (TA EMG)]. Electrodes for electroencephalogram, eye movements, TA EMG, and Di EMG and an arterial catheter were surgically implanted in fetal lambs 123–142 days postconception. Polygraphic recordings were performed without sedation while the ewe breathed room air ( n = 11) or various gas mixtures (hypoxia, n = 5; hyperoxia, n = 4; hypercapnia, n = 5; hypercapnia+hyperoxia, n = 5). Tonic TA EMG was observed throughout >90% of apneas (>6 s) in both non-rapid-eye-movement and rapid-eye-movement sleep, and when Di EMG frequency decreased in rapid-eye-movement sleep. In all but two fetuses, TA EMG was immediately inhibited when Di EMG appeared. Altering blood gases did not modify these results. In conclusion, Di EMG and TA EMG are well coordinated in late gestation in fetal lambs, except in a few cases. These findings may have consequences for understanding the pathogenesis of mixed/obstructive apneas of prematurity.

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Intramuscular and esophageal electrode recordings of posterior cricoarytenoid activity in normal subjects

Journal of Applied Physiology ◽

10.1152/jappl.1990.68.4.1739 ◽

1990 ◽

Vol 68 (4) ◽

pp. 1739-1745 ◽

Cited By ~ 5

Author(s):

S. T. Kuna ◽

J. S. Smickley ◽

G. Insalaco ◽

G. E. Woodson

Keyword(s):

Eye Movement ◽

Human Subjects ◽

Normal Subjects ◽

Rapid Eye Movement ◽

Rapid Eye Movement Sleep ◽

Quiet Breathing ◽

Airway Occlusion ◽

Electrode Activity ◽

Intramuscular Electrodes ◽

Posterior Cricoarytenoid

Six normal human subjects were studied to compare intramuscular and esophageal electrode recordings of posterior cricoarytenoid (PCA) muscle activity. A new electromyographic technique was developed to implant hooked wire electrodes into the PCA via a nasopharyngoscope. The esophageal electrode was similar to that used by other investigators to record PCA activity (P. C. Kosch et al. J. Appl. Physiol. 64: 1968-1978, 1988). Simultaneous recordings from the intramuscular and esophageal electrodes were obtained during wakefulness and sleep. Changes in esophageal electrode activity were compared with changes in intramuscular electrode activity under four conditions: 1) voluntary maneuvers, 2) differences in state, 3) nasal airway occlusion during non-rapid-eye-movement sleep, and 4) spontaneous variations in respiratory efforts during non-rapid-eye-movement or rapid-eye-movement sleep. Although similar results were obtained from the esophageal and intramuscular electrodes, differences were present between the two recordings during both wakefulness and sleep. The esophageal electrode recorded activity from surrounding muscles during voluntary maneuvers, vocalization, and quiet breathing in wakefulness. Discrepancies between the two electrode recordings during sleep occurred under conditions of increased and decreased respiratory motor output. The data suggest that the esophageal electrode may not give an accurate assessment of PCA activity during many conditions in wakefulness and sleep.

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