Laryngeal Dynamics Associated with Voice Frequency Change

1971 ◽  
Vol 14 (4) ◽  
pp. 761-768 ◽  
Author(s):  
Thomas Shipp ◽  
Robert E. McGlone

Simultaneous measures of laryngeal muscle electromyographic activity, subglottal pressure, and air flow were obtained from 14 adult males as they sustained phonation at the 10, 30, 50, 70, and 90% frequency points of their rnodal-to-falsetto range. Frequency was changed throughout the vocal range principally by thyroarytenoid and cricothyroid muscle activity. Further, activity from these two muscles was highly correlated with measures of subglottal pressure. Activity from the posterior cricoarytenoid and interarytenoid muscles and air flow measures showed no systematic pattern related to voice frequency change.

1971 ◽  
Vol 14 (4) ◽  
pp. 769-775 ◽  
Author(s):  
Robert E. McGlone ◽  
Thomas Shipp

Subglottal air pressure, airflow, and electromyographic activity of four intrinsic larygeal muscles were recorded during sustained phonation in the vocal-fry and low-frequency modal registers. Nine young adult males were subjects. In modal phonation there was greater airflow, greater cricothyroid and interarytenoid muscle activity, and decreased thyroarytenoid activity than in vocal fry. No differences were found between registers for subglottal air pressure or posterior cricoarytenoid muscle activity.


1995 ◽  
Vol 32 (5) ◽  
pp. 382-389 ◽  
Author(s):  
Takashi Tachimura ◽  
Hisanaga Hara ◽  
Takeshi Wada

This study was designed to determine if levator veli palatini muscle activity can be elicited by simultaneous changes in oral air pressure and nasal air flow when a speech appliance is in place. The speech appliances routinely worn by 15 subjects were each modified experimentally by drilling a hole in the vertical center of the pharyngeal bulb. The air flow rate into the nasal cavity through the opening in the bulb was altered by changing the circular area of the opening in the bulb from the occluded condition (Condition I), to circular area of 12.6 mm2 (4 mm in diameter; Condition II), and then to 38.5 mm2 (7 mm in diameter; Condition III). Electromyographic activity was measured from the levator veli palatini muscle with changes in nasal air flow rate and oral air pressure. Levator veli palatini muscle activity was correlated with changes in nasal air flow and oral air pressure. Increases in levator veli palatini muscle activity were associated with increases in nasal air flow rate compared to oral air pressure changes. The results indicated that aerodynamic variables of nasal air flow and oral air pressure might be involved in the neural control of speech production in individuals wearing a speech appliance, even if the subjects exhibit velopharyngeal incompetence without using a speech appliance. Also, the stimulating effect of bulb reduction therapy on velopharyngeal function might be achieved through the change in aerodynamic variables in association with the bulb reduction.


1989 ◽  
Vol 98 (5) ◽  
pp. 373-378 ◽  
Author(s):  
Gayle E. Woodson

The cricothyroid muscle (CT) appears to be an accessory muscle of respiration. Phasic inspiratory contraction is stimulated by increasing respiratory demand. Reflex activation of the CT may be responsible for the paramedian position of the vocal folds, and hence airway obstruction, in patients with bilateral recurrent laryngeal nerve (RLN) paralysis. Previous research has demonstrated the influence of superior laryngeal nerve (SLN) afferents on CT activity. The present study addresses the effects of vagal and RLN afferents. Electromyographic activity of the CT and right posterior cricoarytenoid muscle was monitored in anesthetized cats during tracheotomy breathing and in response to tracheal or upper airway occlusion in the intact animal. This was repeated following left RLN transection, bilateral vagotomy, and bilateral SLN transection. Vagotomy abolished CT response to tracheal occlusion and markedly reduced the response to upper airway occlusion. Vocal fold position following RLN transection appeared to correlate with CT activity; however, observed changes were minor.


1989 ◽  
Vol 98 (2) ◽  
pp. 119-124 ◽  
Author(s):  
Gayle E. Woodson ◽  
Oommen Mathew ◽  
Franca Sant'Ambrogio ◽  
Giuseppe Sant'Ambrogio

To determine the functional significance of the cricothyroid muscle (CT) in respiration, laryngeal resistance was measured in anesthetized dogs, along with electromyographic activity of the posterior cricoarytenoid muscle (PCA) and CT. In two dogs the larynx was videotaped simultaneously via a telescope. Increased CT activity was induced by airway occlusion or hypercapnia. Observations were carried out before and during cold blockade of the recurrent laryngeal nerve (RLN) or the nerve to the CT (external branch of the superior laryngeal nerve [Ext SLN]). Paralysis of the CT had no effect on laryngeal resistance or glottic area, even at very high levels of CT activity. Blockade of the RLN increased inspiratory resistance, but did not have a significant effect on expiratory resistance. Electrical stimulation of the Ext SLN produced tetanic CT contraction, which increased laryngeal resistance in both inspiration and expiration. This was true even at very high levels of PCA activity. These results indicate that although artificially induced CT contraction markedly affects laryngeal resistance, physiologic levels of respiratory activity do not have a significant effect.


1991 ◽  
Vol 70 (5) ◽  
pp. 2252-2258 ◽  
Author(s):  
A. Tully ◽  
A. Brancatisano ◽  
S. H. Loring ◽  
L. A. Engel

We examined the effect of posterior cricoarytenoid (PCA) muscle activity on the pressure-flow (PV) relationship of the larynx in five anesthetized tracheostomized dogs. The PCA activity was recorded using bipolar fine-wire electrodes, expressed as a percentage of the quiet breathing level and altered by mechanical ventilation, changes in lung volume, and chest wall compression. Subglottic pressure was recorded while a constant flow of air was passed through the upper airway. In the absence of PCA activity the PV relationship was alinear and could be described by a power function (P = K0Va, where K0 and a are constants). The slope of the log P-log V plots in the absence of PCA and thyroarytenoid activity was 1.83 +/- 0.02 (SD), whereas with increasing PCA activity it was 1.88 +/- 0.11. An effective hydraulic diameter (DH) was calculated for 20% increments of PCA activity, and in two dogs glottic diameter (Dg) was calculated from glottic area measurements obtained by fiber-optic laryngoscopy. Both DH and Dg increased linearly with increasing PCA activity. Denervation of the cricothyroid muscle had no systematic effect on laryngeal resistance. The results indicate that the PV relationship of the larynx may be described by a power function with a single exponent, the magnitude of which is independent of glottic dilator muscle activity and consistent with orifice flow. However, laryngeal diameter increases linearly with PCA activity in the range studied.


2020 ◽  
Vol 11 (1) ◽  
pp. 7
Author(s):  
Antonino Casabona ◽  
Maria Stella Valle ◽  
Claudio Dominante ◽  
Luca Laudani ◽  
Maria Pia Onesta ◽  
...  

The benefits of functional electrical stimulation during cycling (FES-cycling) have been ascertained following spinal cord injury. The instrumented pendulum test was applied to chronic paraplegic patients to investigate the effects of FES-cycling of different duration (20-min vs. 40-min) on biomechanical and electromyographic characterization of knee mobility. Seven adults with post-traumatic paraplegia attended two FES-cycling sessions, a 20-min and a 40-min one, in a random order. Knee angular excursion, stiffness and viscosity were measured using the pendulum test before and after each session. Surface electromyographic activity was recorded from the rectus femoris (RF) and biceps femoris (BF) muscles. FES-cycling led to reduced excursion (p < 0.001) and increased stiffness (p = 0.005) of the knee, which was more evident after the 20-min than 40-min session. Noteworthy, biomechanical changes were associated with an increase of muscle activity and changes in latency of muscle activity only for 20-min, with anticipated response times for RF (p < 0.001) and delayed responses for BF (p = 0.033). These results indicate that significant functional changes in knee mobility can be achieved by FES-cycling for 20 min, as evaluated by the pendulum test in patients with chronic paraplegia. The observed muscle behaviour suggests modulatory effects of exercise on spinal network aimed to partially restore automatic neuronal processes.


1997 ◽  
Vol 106 (11) ◽  
pp. 897-901 ◽  
Author(s):  
Robert G. Berkowitz ◽  
John Chalmers ◽  
Qi-Jian Sun ◽  
Paul M. Pilowsky

An anatomic and electrophysiological study of the rat posterior cricoarytenoid (PCA) muscle is described. The intramuscular nerve distribution of the PCA branch of the recurrent laryngeal nerve was demonstrated by a modified Sihler's stain. The nerve to the PCA was found to terminate in superior and inferior branches with a distribution that appeared to be confined to the PCA muscle. Electromyography (EMG) recordings of PCA muscle activity in anesthetized rats were obtained under stereotaxic control together with measurement of phrenic nerve discharge. A total of 151 recordings were made in 7 PCA muscles from 4 rats. Phasic inspiratory activity with a waveform similar to that of phrenic nerve discharge was found in 134 recordings, while a biphasic pattern with both inspiratory and post-inspiratory peaks was recorded from random sites within the PCA muscle on 17 occasions. The PCA EMG activity commenced 24.6 ± 2.2 milliseconds (p < .0001) before phrenic nerve discharge. The results are in accord with findings of earlier studies that show that PCA muscle activity commences prior to inspiratory airflow and diaphragmatic muscle activity. The data suggest that PCA and diaphragm motoneurons share common or similar medullary pre-motoneurons. The earlier onset of PCA muscle activity may indicate a role for medullary pre-inspiratory neurons in initiating PCA activity.


1999 ◽  
Vol 86 (5) ◽  
pp. 1663-1669 ◽  
Author(s):  
A. L. Perlman ◽  
P. M. Palmer ◽  
T. M. McCulloch ◽  
D. J. Vandaele

The durations and temporal relationships of electromyographic activity from the submental complex, superior pharyngeal constrictor, cricopharyngeus, thyroarytenoid, and interarytenoid muscles were examined during swallowing of saliva and of 5- and 10-ml water boluses. Bipolar, hooked-wire electrodes were inserted into all muscles except for the submental complex, which was studied with bipolar surface electrodes. Eight healthy, normal, subjects produced five swallows of each of three bolus volumes for a total of 120 swallows. The total duration of electromyographic activity during the pharyngeal stage of the swallow did not alter with bolus condition; however, specific muscles did show a volume-dependent change in electromyograph duration and time of firing. Submental muscle activity was longest for saliva swallows. The interarytenoid muscle showed a significant difference in duration between the saliva and 10-ml water bolus. Finally, the interval between the onset of laryngeal muscle activity (thyroarytenoid, interarytenoid) and of pharyngeal muscle firing patterns (superior pharyngeal constrictor onset, cricopharyngeus offset) decreased as bolus volume increased. The pattern of muscle activity associated with the swallow showed a high level of intrasubject agreement; the presence of somewhat different patterns among subjects indicated a degree of population variance.


1995 ◽  
Vol 79 (2) ◽  
pp. 448-454 ◽  
Author(s):  
I. L. Mortimore ◽  
R. Mathur ◽  
N. J. Douglas

Sleep apnea is worse in the supine posture and is associated with retropalatal airway narrowing or occlusion. We have, therefore, examined the effects of posture, negative pressure, and route of respiration on palatal muscle activity in 13 nonsnoring awake male subjects by using electromyography. Electromyographic activity of the levator palatini and palatoglossus was expressed as a percentage of maximum activity. Both the levator palatini (P = 0.002) and palatoglossus (P = 0.002) exhibited phasic inspiratory activity. Overall, posture did not affect the levator palatini (F = 1.58; P = 0.23) or palatoglossus (F = 0.98; P = 0.34) activity, but analysis by route of respiration showed the palatoglossus to be more active when the subjects were nose breathing supine (F = 6.64; P = 0.02). Levator palatini activity was lower when nose breathing was compared with mouth breathing in both the erect and supine postures (F = 6.67; P < 0.02). Nose breathing with the mouth held open caused an increase in palatoglossal activity (P = 0.04). Negative-pressure application (0 to -12.5 cmH2O) caused significant increases in levator palatini (P < 0.001) and palatoglossus (P < 0.001) activity, 100 ms after pressure stimulus, irrespective of route. However, the palatoglossus required significantly greater negative pressures to cause activation when applied via the nose compared with the mouth (P < 0.05). These observations indicate that the levator palatini and palatglossus have respiratory activity and are reflexly activated by negative pressure.


1990 ◽  
Vol 99 (3) ◽  
pp. 167-174 ◽  
Author(s):  
Ian N. Jacobs ◽  
Bei-Lian Wu ◽  
Ira Sanders ◽  
Hugh F. Biller

This experiment investigated the reinnervation of the canine posterior cricoarytenoid (PCA) muscle with preganglionic neurons of the sympathetic nervous system. Six dogs had their right recurrent laryngeal nerve (RLN) sectioned. Four of these dogs had the sympathetic cervical trunk (SCT) implanted into the right PCA muscle, and the two remaining dogs served as denervated controls. Four months later all dogs underwent videolaryngoscopy, electromyography, and electrical stimulation of the SCT. The PCA muscles were excised, sectioned, and stained for glycogen and ATPase. All four experimental PCA muscles demonstrated electrically evoked abduction and tonic electromyographic activity. In two of the specimens, staining (ATPase and PAS) revealed areas of reinnervation with fiber type grouping and glycogen depletion. These results are consistent with the successful reinnervation of the PCA muscle. Further refinement of this technique could be of benefit to patients with bilateral vocal cord paralysis.


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