人間の昼間の時計を光でリセットするための用量反応関係
D B Boivin1, J F Duffy, R E Kronauer
1Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.
Nature
|February 8, 1996
まとめ
人間の昼夜ペースメーカーは,これまで考えられていたよりも光に敏感です. 室内照明レベルが低い場合でも (約180ルックス) は,身体の位置を大きく変化させることができます.
科学分野:
- クロノバイオロジー クロノバイオロジー
- 人間の生理学 人間生理学
- スリープ・サイエンス スリープ・サイエンス
背景:
- 光は,種間の内生性昼夜ペースメーカーのシンクロナイザーとして知られています.
- 明るい光 (7,00013,000 ルックス) は,人間の昼夜リズムを効果的に同期します.
- 一般的な考えでは,ヒトの昼夜ペースメーカーが,典型的な室内照明 (50300 lux) に無感であると考えられています.
研究 の 目的:
- 人間の昼夜ペースメーカーは,より低い光の強度に対して敏感であるという仮説を検証するために.
- 室内の照明レベルがヒトの昼間ペースメーカーのフェーズシフトを有意に変化させるかどうかを判断する.
- ヒトの昼夜連動メカニズムを他の哺乳類のそれと比較する.
主な方法:
- 人間の参加者を制御された光の強度にさらした実験を行った.
- 低強度の光 (約180ルックス) が人間の昼夜ペースメーカーに及ぼす相変化効果を測定した.
- 照明曝露と昼夜リズムリセットの強度依存関係を分析した.
主要な成果:
- 比較的低い強度 (約180ルックス) の光の曝露は,ヒトの昼夜ペースメーカーの相変化を著しく引き起こした.
- 人間は,これまで考えられていたよりも,光の昼夜を左右する影響に対して,かなり敏感であることが示された.
- 人間の昼夜ペースメーカーに対する光のリセット効果は,圧縮非線形機能に従っている.
結論:
- 人間の昼夜ペースメーカーは,通常の室内の照明レベルに対して敏感です.
- ヒトは,その昼夜間の誘導メカニズムに関して,他の哺乳類と質的に異なるものではありません.
- 低い光の強度は,日中リズム同期に強い影響を及ぼします.
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