Phasic tongue movements in human rapid eye-movement sleep

Area of Science:

• Neurology
• Sleep Medicine
• Respiratory Physiology

Background:

• Obstructive sleep apnea (OSA) is often exacerbated during REM sleep.
• Genioglossal muscle hypotonia during REM sleep can lead to posterior tongue displacement and airway obstruction.
• Understanding compensatory mechanisms is crucial for managing sleep-related breathing disorders.

Purpose of the Study:

• To investigate the nature and potential function of complex tongue movements during REM sleep.
• To determine if these movements are a protective response against airway collapse in various patient groups and healthy individuals.

Main Methods:

• Polygraphic recordings were used to monitor sleep stages and oromotor activity.
• Analysis focused on phasic tongue movements during REM sleep across different participant groups.

Main Results:

• Unusual, complex tongue movements were identified as phasic phenomena during REM sleep in patients with narcolepsy, sleep apnea syndrome, posterior fossa lesions, and normal controls.
• These movements appear to counteract posterior tongue displacement, potentially preventing obstructive sleep apnea.

Conclusions:

• Complex tongue movements during REM sleep may serve as a protective mechanism against obstructive sleep apnea.
• Genioglossal hypotonia during REM sleep is a risk factor for OSA, but these observed tongue movements might mitigate this risk.