Genioglossus (GG) electrical activity [measured by electromyogram (EMGgg)] is best measured by intramuscular electrodes; however, the homogeneity of EMGgg is undefined. We investigated the relationships between EMGgg and the site from which activity was measured to determine whether and to what extent inhomogeneity in activity occurred. Eight healthy human volunteers underwent ultrasound to determine GG depth and width. Four pairs of electrodes were then inserted percutaneously into the left and right GG muscle, anteriorly and posteriorly. Additional configurations were obtained by connecting electrodes across the midline and along each muscle belly. EMGgg activity was simultaneously recorded from these 10 configurations at rest and during various respiratory maneuvers. Heterogeneous behavior of the GG was evidenced by 1) the variable presence of phasic EMGgg at rest, which was undetectable in two subjects but evident in 65% of configurations in six subjects and present in all configurations in all subjects during voluntary hyperventilation; 2) a greater amplitude of EMGgg response to pharyngeal square-wave negative pressure in anterior than posterior configurations (14.1 +/- 7.1 vs. 8.5 +/- 5.1% of maximum, P < 0.05); and 3) variable (linear and alinear) relationships between EMGgg and lingual force within and between subjects. We hypothesize that regional differences in density and type of muscle fiber are the most likely sources of heterogeneity in these responses.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1152/japplphysiol.01017.2002 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Systemic Administration of Tempol, a Superoxide Dismutase Mimetic, Augments Upper Airway Muscle Activity in Obese Zucker Rats.
Front Pharmacol
February 2022
Department of Pediatrics, Division of Pulmonology, Allergy and Immunology, School of Medicine, Case Western Reserve University, Cleveland, OH, United States.
Obstructive sleep apnea (OSA) is characterized by repetitive partial/complete collapse of the pharynx during sleep, which results in apnea/hypopnea leading to arterial oxygen desaturations and arousals. Repetitive apnea/hypopnea-arousal episodes cause hypoxia/reoxygenation cycles, which increase free radical generation and oxidative stress that cause motor/sensory nerve impairments and muscle damage. We hypothesize that antioxidants may protect and/or reverse from oxidative stress-induced damage in OSA patients.
View Article and Find Full Text PDFGenioglossus muscle responses to resistive loads in severe OSA patients and healthy control subjects.
J Appl Physiol (1985)
December 2019
Institute for Breathing and Sleep, Austin Health, Heidelberg, Victoria, Australia.
This study aimed to determine whether there is impairment of genioglossus neuromuscular responses to small negative pressure respiratory stimuli, close to the conscious detection threshold, in obstructive sleep apnea (OSA). We compared genioglossus electromyogram (EMGgg) responses to midinspiratory resistive loads of varying intensity (≈1.2-6.
View Article and Find Full Text PDFUpper airway collapsibility and genioglossus activity in adolescents during sleep.
Sleep
October 2012
The Sleep Center and Biostatistics Core, Clinical and Translational Research Center, Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, PA, USA.
Article Synopsis
- Obese patients often experience obstructive sleep apnea syndrome (OSAS), but not all obese adolescents do, leading researchers to investigate the reasons behind this.
- The study involved monitoring 35 patients with OSAS, 28 obese controls, and 43 lean controls to assess their neuromuscular responses during sleep under various pressure conditions.
- Results showed that obese controls exhibited stronger neuromuscular responses in the upper airway, helping prevent collapse during sleep, suggesting these protective mechanisms might decline for those who eventually develop OSAS.
Effect of age and weight on upper airway function in a mouse model.
J Appl Physiol (1985)
September 2011
Division of Pulmonary and Critical Care Medicine, Department of Medicine, The Johns Hopkins Medical Institutions, Baltimore, Maryland, USA.
Defects in pharyngeal mechanical and neuromuscular control are required for the development of obstructive sleep apnea. Obesity and age are known sleep apnea risk factors, leading us to hypothesize that specific defects in upper airway neuromechanical control are associated with weight and age in a mouse model. In anesthetized, spontaneously breathing young and old wild-type C57BL/6J mice, genioglossus electromyographic activity (EMG(GG)) was monitored and upper airway pressure-flow dynamics were characterized during ramp decreases in nasal pressure (Pn, cmH₂O).
View Article and Find Full Text PDFThe effect of gender on compensatory neuromuscular response to upper airway obstruction in normal subjects under midazolam general anesthesia.
Anesth Analg
October 2009
Department of Clinical Physiology, Nagasaki University Graduate School of Biomedical Science, 1-7-1 sakamoto, Nagasaki-shi 852-8588, Japan.
Background: Upper airway patency may be compromised during sleep and anesthesia by either anatomical alterations (mechanical properties) or disturbances in the neural control (compensatory neuromuscular responses). The pathophysiology of upper airway obstruction during anesthesia may differ between men and women. Recently, we reported that the upper airway mechanical properties were comparable with those found during natural nonrapid eye movement sleep, as evaluated by measurements of passive critical closing pressure (P(CRIT)) and upstream resistance (R(US)) during midazolam sedation.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!