Replay bursts in humans coincide with activation of the default mode and parietal alpha networks

Summary

Our brains at rest spontaneously replay recently acquired information, but how this process is orchestrated to avoid interference with ongoing cognition is an open question. Here we investigated whether replay coincided with spontaneous patterns of whole-brain activity. We found, in two separate datasets, that replay sequences were packaged into transient bursts occurring selectively during activation of the default mode network (DMN) and parietal alpha networks. These networks are believed to support inwardly oriented attention and inhibit bottom-up sensory processing and were characterized by widespread synchronized oscillations coupled to increases in high frequency power, mechanisms thought to coordinate information flow between disparate cortical areas. Our data reveal a tight correspondence between two widely studied phenomena in neural physiology and suggest that the DMN may coordinate replay bursts in a manner that minimizes interference with ongoing cognition.

Highlights

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  Replay in humans coincides with activity in specific resting brain networks

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  Clusters of heightened default mode and alpha activity are linked to replay bursts

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  These networks are characterized by highly synchronized brain-wide oscillations

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  High-frequency power bursts are uniquely linked to default mode network activation

Abstract

Our brains form stable memory traces by spontaneously replaying recently acquired information. Higgins et al. show that this process coincides with activity in specific resting-state brain networks, with bursts of replay events occurring selectively during clusters of heightened default mode and parietal alpha network activity.