Individual variability in neural representations of mind-wandering

Summary

Mind-wandering, a common daily mental activity, varies uniquely from person to person. In three individuals who each reported hundreds of mind-wandering episodes during multiple fMRI sessions, reliable links between mind-wandering and default mode network (DMN) activation emerged when brain networks were analyzed within each person. However, the timing of spontaneous DMN activity relative to subjective reports, and the broader networks activated or deactivated during mind-wandering, differed across individuals. Whole-brain connectivity patterns that predicted mind-wandering within an individual did not fully generalize to others, and predictive models from larger datasets largely failed when applied to these densely-sampled individuals. This work demonstrates both conserved and variable neural representations of mind-wandering, highlighting the value of personalized approaches.

Study at a glance

Abstract

Mind-wandering is a frequent, daily mental activity, experienced in unique ways in each person. Yet neuroimaging evidence relating mind-wandering to brain activity, for example in the default mode network (DMN), has relied on population-rather than individual-based inferences due to limited within-individual sampling. Here, three densely-sampled individuals each reported hundreds of mind-wandering episodes while undergoing multi-session functional magnetic resonance imaging. We found reliable associations between mind-wandering and DMN activation when estimating brain networks within individuals using precision functional mapping. However, the timing of spontaneous DMN activity relative to subjective reports, and the networks beyond DMN that were activated and deactivated during mind-wandering, were distinct across individuals. Connectome-based predictive modeling further revealed idiosyncratic, whole-brain functional connectivity patterns that consistently predicted mind-wandering within individuals but did not fully generalize across individuals. Predictive models of mind-wandering and attention that were derived from larger-scale neuroimaging datasets largely failed when applied to densely-sampled individuals, further highlighting the need for personalized models. Our work offers novel evidence for both conserved and variable neural representations of self-reported mind-wandering in different individuals. The previously-unrecognized inter-individual variations reported here underscore the broader scientific value and potential clinical utility of idiographic approaches to brain-experience associations.