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bioRxiv · 10.1101/2020.08.20.258517

Time-of-day influence on resting-state fMRI: an overlooked factor contributing to the replication crisis?

Vaisvilaite, L.·Hushagen, V.·Gronli, J.·Specht, K.
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Abstract

The current project explored the hypothesis that time-of-day dependent metabolic variations may contribute to reduced reliability in resting-state fMRI studies. We have investigated time-of-day effects in the spontaneous fluctuations (>0.1Hz) of the blood oxygenation level dependent (BOLD) signal. Using data from the human connectome project (HCP) release S1200, cross-spectral density dynamic causal modelling (DCM) was used to analyze time-dependent effects on the hemodynamic response and effective connectivity parameters. Hierarchical group-parametric empirical Bayes (PEB) found no support for changes in effective connectivity, whereas the hemodynamic parameters exhibited a significant time-of-day dependent effect. We conclude that these findings urge the need to account for the time of data acquisition in future MRI studies.

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Vaisvilaite, L., Hushagen, V., Gronli, J., Specht, K.. 2020-08-20. Time-of-day influence on resting-state fMRI: an overlooked factor contributing to the replication crisis?. https://doi.org/10.1101/2020.08.20.258517

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