Does our mood change as time passes? This question is central to behavioural and affective science, yet it remains largely unexamined. To investigate, we intermixed subjective momentary mood ratings into repetitive psychology paradigms. Here we demonstrate that task and rest periods lowered participants’ mood, an effect we call ‘Mood Drift Over Time’. This finding was replicated in 19 cohorts totalling 28,482 adult and adolescent participants. The drift was relatively large (−13.8% after 7.3 min of rest, Cohen’s d = 0.574) and was consistent across cohorts. Behaviour was also impacted: participants were less likely to gamble in a task that followed a rest period. Importantly, the drift slope was inversely related to reward sensitivity. We show that accounting for time using a linear term significantly improves the fit of a computational model of mood. Our work provides conceptual and methodological reasons for researchers to account for time’s effects when studying mood and behaviour.
|Number of pages||15|
|Journal||Nature Human Behaviour|
|Early online date||27 Feb 2023|
|State||Published - Apr 2023|
Bibliographical noteFunding Information:
This research was supported in part by the Intramural Research Program of the National Institute of Mental Health, part of the NIH (grant nos. ZIAMH002957 (to A.S.), ZICMH002968 (to F.P.), ZIAMH002871 (to D.S.P.), ZIAMH002872 (to D.S.P.) and ZICMH002960 (to A.G.T.)). This work used the computational resources of the NIH high-performance computing (HPC) Biowulf cluster ( http://hpc.nih.gov ). Data collection for the mobile app dataset was supported by the Wellcome Trust (grant no. 101252/Z/13/Z). The online adolescent sample in this study was collected under NIH IRB protocol number 18-M-0037, registered on clinicaltrials.gov as NCT03388606. The online adult sample was collected under NIH Office of Human Subjects Research Protection protocol P194594. The funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript. The views expressed in this article do not necessarily represent the views of the NIH, the Department of Health and Human Services or the United States Government.
© 2023, This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.