Patterns of Brain Activity Supporting Autobiographical Memory, Prospection, and Theory of Mind, and Their Relationship to the Default Mode Network

TLDR

The default mode network (DMN) is thought to support self‑referential processes such as autobiographical memory, prospection, and theory of mind, but this hypothesis had not been directly tested. The authors used fMRI to record brain activity while participants performed autobiographical remembering, prospection, and theory‑of‑mind reasoning. Multivariate analysis revealed a shared DMN activation pattern across all three tasks, with autobiographical memory and prospection preferentially engaging midline DMN regions and theory of mind engaging lateral DMN, and medial prefrontal cortex activity correlated with other DMN nodes during each task.

Abstract

Abstract The ability to rise above the present environment and reflect upon the past, the future, and the minds of others is a fundamentally defining human feature. It has been proposed that these three self-referential processes involve a highly interconnected core set of brain structures known as the default mode network (DMN). The DMN appears to be active when individuals are engaged in stimulus-independent thought. This network is a likely candidate for supporting multiple processes, but this idea has not been tested directly. We used fMRI to examine brain activity during autobiographical remembering, prospection, and theory-of-mind reasoning. Using multivariate analyses, we found a common pattern of neural activation underlying all three processes in the DMN. In addition, autobiographical remembering and prospection engaged midline DMN structures to a greater degree and theory-of-mind reasoning engaged lateral DMN areas. A functional connectivity analysis revealed that activity of a critical node in the DMN, medial prefrontal cortex, was correlated with activity in other regions in the DMN during all three tasks. We conclude that the DMN supports common aspects of these cognitive behaviors involved in simulating an internalized experience.