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Polygraphic Recording Procedure for Measuring Sleep in Mice
Published on: January 25, 2016
Relationship between muscle tone changes, sawtooth waves and rapid eye movements during sleep
S Sato1, C McCutchen, B Graham
1EEG Section, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892-1404, USA. sato@helix.nih.gov
Electroencephalography and Clinical Neurophysiology
|April 18, 1998
Summary
Sawtoothed waves (STW) appear after muscle tone reduction (MTR) and before rapid eye movement (REM) sleep onset. This predictable sequence suggests a new understanding of REM sleep initiation.
Area of Science:
- Neuroscience
- Sleep Science
Background:
- Sawtoothed waves (STW) are observed during rapid eye movement (REM) sleep.
- The origin and function of STW remain unclear.
Purpose of the Study:
- To investigate the temporal relationship between the onset of STW, muscle tone reduction (MTR), and REM sleep.
Main Methods:
- Analysis of 20 polysomnographic recordings from 11 healthy volunteers.
- Examined 91 REM sleep cycles, focusing on the sequence of generalized body movement, MTR, STW, and REM.
Main Results:
- A consistent sequence was observed: body movement, followed by MTR, then STW, and finally REM.
- STW onset significantly preceded REM onset (mean difference: 70s).
- MTR onset also significantly preceded STW onset (mean difference: 111s).
Conclusions:
- The data indicate a predictable sequence of MTR, STW, and REM sleep.
- This sequence challenges the traditional definition of REM sleep onset.
- Findings may necessitate a re-evaluation of the physiological onset of REM sleep.
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