Related Experiment Video
Updated: Nov 20, 2025
08:51
Statistical Modelling of Cortical Connectivity Using Non-invasive Electroencephalograms
Published on: November 1, 2019
5.9K
Identifying Diurnal Variability of Brain Connectivity Patterns Using Graph Theory
Farzad V Farahani1, Magdalena Fafrowicz2,3, Waldemar Karwowski1
1Computational Neuroergonomics Laboratory, Department of Industrial Engineering and Management Systems, University of Central Florida, Orlando, FL 32816, USA.
Brain Sciences
|January 20, 2021
Summary
Brain network organization varies with time of day, not chronotype. Evening scans showed higher efficiency, suggesting sleep inertia influences brain function shortly after waking.
Area of Science:
- Neuroscience
- Network Science
- Cognitive Neuroscience
Background:
- Human brain function is influenced by time of day and individual chronotypes.
- These factors are often overlooked in neuroimaging studies.
- Understanding temporal brain dynamics is crucial for interpreting functional connectivity.
Purpose of the Study:
- To investigate the impact of time of day and chronotype on whole-brain network organization.
- To analyze resting-state functional MRI (rs-fMRI) data using network neuroscience approaches.
- To determine if temporal variations affect brain network efficiency and local connectivity.
Main Methods:
- Utilized resting-state functional MRI (rs-fMRI) data from 62 participants.
- Assessed network neuroscience metrics, including small-worldness and local graph measures.
- Collected data during morning and evening sessions, relative to wake-up time.
Main Results:
- Found significant effects of time of day on brain connectivity profiles.
- Observed higher small-worldness in the evening compared to the morning session.
- Identified changes in local graph measures, particularly in the left hemisphere and cerebellum, in the evening.
Conclusions:
- Brain functional network architecture exhibits daily variability.
- Time of day, rather than chronotype, significantly impacts brain network organization.
- Early morning brain function may be influenced by sleep inertia, overriding circadian and homeostatic processes.
