Heimola Mikko, Paulanto Kaisu, Alakuijala Anniina, Tuisku Katinka, Simola Petteri, Ämmälä Antti-Jussi, Räisänen Pekka, Parkkola Kai, Paunio Tiina
Department of Psychiatry, University of Helsinki and HUS Helsinki University Hospital, Helsinki, Finland.
Department of Clinical Neurophysiology, HUS Medical Imaging Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.
Sleep Adv. 2021 Oct 18;2(1):zpab016. doi: 10.1093/sleepadvances/zpab016. eCollection 2021.
We set out to examine how chronotype (diurnal preference) is connected to ability to function in natural conditions where individuals cannot choose their sleep schedule. We conducted a cross-sectional study in military conscript service to test the hypothesis that sleep deprivation mediates the adverse effects of chronotype on cognitive functioning. We also examined the effects of time of day.
One hundred forty participants (ages 18-24 years) completed an online survey, including the Morningness-Eveningness Questionnaire and a Cambridge Neuropsychological Test Automated Battery. Most ( = 106) underwent an actigraphy recording. After bivariate analyses, we created a mediation model (self-reported sleepiness and sleep deprivation mediating effect of chronotype on cognition) and a moderation model (synchrony between most alert time and testing time).
Reaction times in inhibition task correlated negatively with sleep efficiency and positively with sleep latency in actigraphy. There was no relation to ability to inhibit responses. More significantly, spatial working memory performance (especially strategicness of performance) correlated positively with morning preference and negatively with sleep deprivation before service. Synchrony with most alert time of the day did not moderate these connections. No other cognitive task correlated with morningness or sleep variables.
In line with previous research, inhibitory control is maintained after insufficient sleep but with a tradeoff of slower performance. The connection between morning preference and working memory strategy is a novel finding. We suggest that diurnal preference could be seen as an adaptive strategy, as morningness has consistently been associated with better academic and health outcomes.
我们着手研究昼夜节律类型（昼夜偏好）如何与个体无法选择睡眠时间表的自然条件下的功能能力相关联。我们在义务兵役期间进行了一项横断面研究，以检验睡眠剥夺介导昼夜节律类型对认知功能产生不利影响这一假设。我们还研究了一天中不同时间的影响。
140名参与者（年龄在18 - 24岁之间）完成了一项在线调查，包括晨型 - 夜型问卷和剑桥神经心理测试自动成套测验。大多数人（n = 106）进行了活动记录仪记录。经过双变量分析后，我们创建了一个中介模型（自我报告的困倦和睡眠剥夺在昼夜节律类型对认知的影响中的中介作用）和一个调节模型（最警觉时间与测试时间之间的同步性）。
在活动记录仪中，抑制任务的反应时间与睡眠效率呈负相关，与睡眠潜伏期呈正相关。与抑制反应的能力无关。更显著的是，空间工作记忆表现（尤其是表现的策略性）与晨型偏好呈正相关，与服役前的睡眠剥夺呈负相关。与一天中最警觉时间的同步性并未调节这些关联。没有其他认知任务与晨型或睡眠变量相关。
与先前的研究一致，睡眠不足后抑制控制得以维持，但代价是表现变慢。晨型偏好与工作记忆策略之间的联系是一项新发现。我们认为昼夜偏好可被视为一种适应性策略，因为晨型一直与更好的学业和健康结果相关联。
