Generation of REM twitches in jaw muscles during REM sleep

2014 Fiscal Year Final Research Report

• Project/Area Number: 25670789
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Functional basic dentistry
• Research Institution: Osaka University
• Principal Investigator: TAKAFUMI Kato 大阪大学, 歯学研究科(研究院), 講師 (50367520)
• Co-Investigator(Kenkyū-buntansha): YOSHIDA Atsushi 大阪大学, 大学院歯学研究科, 教授 (90201855)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: REM睡眠 / リズム発生機構 / 咀嚼筋 / 大脳皮質 / 睡眠関連運動異常症

Outline of Final Research Achievements

Neural mechanisms for the genesis of rhythmic jaw movements (RJMs) during REM sleep remain unknown. We found the distinct patterns of descending projections from sensori-motor cortex to subcortical structures in diencephalon, midbrain, pons and medulla, including masticatory motor system. Then we succeeded to induce RJMs during REM sleep using electrical microstimulation to cortical the descending fibers. However, the motor threshold for the genesis of the RJMs was significantly higher during REM sleep than NREM sleep and wakefulness. Therefore, the data suggest that facilitatory inputs through cortical descending tracts can activate masticatory rhythm generator during REM sleep when these inputs are strong enough to overcome motor inhibition.

Free Research Field

口腔解剖学