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Updated: Jun 16, 2026
10:16
Human Circadian Phenotyping and Diurnal Performance Testing in the Real World
Published on: April 7, 2020
Chronotype and Time of Day Effects in Oddball Task Performance: Behavioural and Cerebral Correlates
Christina Schmidt1,2, Gilles Vandewalle1, Christian Cajochen3
1GIGA-CRC Human Imaging, University of Liège, Liege, Belgium.
Journal of Sleep Research
|June 15, 2026
Summary
Chronotype and time of day impact cognitive performance through the synchrony effect. Brain activity in the inferior frontal cortex and medial orbitofrontal cortex reflects optimal versus non-optimal timing for attention and cognitive control.
Area of Science:
- Cognitive Neuroscience
- Chronobiology
- Neuroimaging
Background:
- Circadian rhythms and individual chronotypes significantly influence cognitive functions like attention and memory.
- The synchrony effect, or alignment between an individual's chronotype and time of day, modulates cognitive performance.
- Understanding these effects is crucial for optimizing task scheduling and performance in daily life.
Purpose of the Study:
- To investigate the behavioral and neural underpinnings of synchrony effects on cognitive performance.
- To examine how chronotype and time of day interact to affect attention and executive control during a cognitive task.
- To identify brain regions associated with optimal versus non-optimal timing relative to an individual's chronotype.
Main Methods:
- Functional magnetic resonance imaging (fMRI) and behavioral assessments were used.
- Participants included extreme morning-type and evening-type individuals.
- An auditory oddball task was administered during morning and evening sessions.
Main Results:
- No overall effects of chronotype or time of day on reaction times were found.
- Reaction times increased in the evening compared to the morning for morning types, but not evening types, in the latter part of the task.
- fMRI revealed increased activation in the inferior frontal cortex (IFC) during optimal synchrony, suggesting enhanced top-down control.
- Increased medial orbitofrontal cortex (mOFC) activity, associated with the default mode network, was observed during non-optimal synchrony, indicating reduced task engagement.
Conclusions:
- Synchrony effects interact with time-on-task, influencing sustained attention.
- The IFC and mOFC play distinct roles in modulating cognitive control based on chronotype and time of day.
- These findings have implications for understanding and managing cognitive performance in real-world settings based on individual biological rhythms.
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