Thalamic deactivation at sleep onset precedes that of the cerebral cortex in humans.
Magnin M, Rey M, Bastuji H, Guillemant P, Mauguiere F, Garcia-Larrea L.
Thalamic and cortical activities are assumed to be time-locked throughout all vigilance states. Using simultaneous intracortical and intrathalamic recordings,
we demonstrate here that the thalamic deactivation occurring at sleep onset most often precedes that of the cortex by several minutes, whereas reactivation of both structures during awakening is synchronized. Delays between thalamus and cortex deactivations can vary from one subject to another when a similar cortical region is considered. In addition, heterogeneity in activity levels throughout the cortical mantle is larger than previously thought during the descent into sleep. Thus, asynchronous thalamo-cortical deactivation while falling asleep probably explains the production of hypnagogic hallucinations by a still-activated cortex and the common self-overestimation of the time needed to fall asleep.＝＝＝
●入眠時にThalamusのほうがcortexより活動が早く（数分～数十分）ことを、ヒト検体を用いて検証。覚醒時はほぼ同時。
●the dimention of activation (DA)という、波形解析のアルゴリズムを用いて脳波を解析→大きな同期性徐波が出る睡眠時は数値が低下、ランダムで細かな波がでる覚醒時は数値が増加
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