人間の昼夜ペースメーカーの安定性,精度,および24時間近くの周期
C A Czeisler1, J F Duffy, T L Shanahan
1Circadian, Neuroendocrine, and Sleep Disorders Section, Division of Endocrinology, Department of Medicine, Harvard Medical School, Brigham and Women's Hospital, 221 Longwood Avenue, Boston, MA 02115, USA.
Science (New York, N.Y.)
|June 26, 1999
まとめ
人間の昼夜リズムは,年齢によって一貫しており,平均24.18時間です. これは以前の仮定に異議を唱え,高齢者の睡眠障害に関する新しい洞察を提供します.
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:
- 以前の研究では,ヒトの昼間の周期が大きく変化し,年齢とともに短縮することが示唆されていた.
- これらの以前の発見は,正確な期間推定に干渉する可能性がある照明条件下で実施された研究に基づいていました.
- 人間の昼夜リズムと他の種の昼夜リズムとの間に不一致が認められた.
研究 の 目的:
- 制御された照明下でヒトの内生的な昼夜リズム期間を正確に推定するために.
- 若年,高齢の健康な個人の内在的な昼夜周期を比較する.
- 人間の昼夜ペースメーカーの周期とその一貫性を再評価する.
主な方法:
- 健康な若者や高齢者を採用した.
- 照明汚染を防ぐために,慎重に制御された照明条件で研究を行った.
- メラトニン,核心体温,コルチゾールレベルを含む内生的な昼夜リズムを正確に測定しました.
主要な成果:
- ヒトの昼夜ペースメーカーの内在期間は,若年および高齢者の両方で平均24.18時間です.
- この期間の分布は,他の種での発見と一致し,緊密であることが判明しました.
- 年齢層の間では,昼間の周期に有意な差は認められませんでした.
結論:
- 人間の昼間の周期は,異なる年齢層にわたって本質的に一貫しており,平均約24.18時間です.
- この発見は,ヒトの昼夜リズムの変化性に関する以前の誤解を正している.
- この結果は,年齢に関連する睡眠障害とその根本的なメカニズムを理解するための基礎を提供します.
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