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Updated: Jul 14, 2026
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Quantifying Infra-slow Dynamics of Spectral Power and Heart Rate in Sleeping Mice
Published on: August 2, 2017
Central slowing during the night
Daniel Bratzke1, Bettina Rolke, Rolf Ulrich
1University of Tübingen, Tübingen, Germany. daniel.bratzke@uni-tuebingen.de
Psychological Science
|June 20, 2007
Summary
Central information processing, measured by reaction time (RT), follows a circadian rhythm. This processing slows during the night and is slowest in the early morning, impacting cognitive performance.
Area of Science:
- Chronobiology
- Cognitive Psychology
- Human Physiology
Background:
- Reaction time (RT) varies throughout the day, a phenomenon known as the time-of-day effect.
- The underlying mechanisms, particularly the role of central information processing, remain incompletely understood.
- The psychological refractory period (PRP) paradigm offers a method to chronometrically assess central processing duration.
Purpose of the Study:
- To investigate whether central information processing exhibits a circadian rhythm.
- To determine if circadian variations in central processing contribute to the time-of-day effect on reaction time.
- To chronometrically assess the duration of central processing using the PRP paradigm.
Main Methods:
- Participants performed the psychological refractory period (PRP) task under controlled conditions.
- The PRP task involved making rapid responses to two successive stimuli.
- Data were collected every 2 hours during 28 hours of continuous wakefulness.
Main Results:
- The PRP effect, indicative of central processing limitations, was most pronounced in the early morning.
- This suggests that central processing speed is slowest during the night and early morning hours.
- The findings demonstrate a clear circadian modulation of central information processing.
Conclusions:
- Central information processing is subject to a significant circadian rhythm.
- Circadian variations in central processing contribute to the observed time-of-day effects on cognitive performance, specifically reaction time.
- Cognitive function, particularly the speed of central processing, exhibits a daily pattern with reduced efficiency during the night and early morning.
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