Cortical and Hippocampal Pathways to Mental Continuity

Abstract

How do people preserve mental continuity when tasks are interrupted? One established pathway runs through the hippocampus, which stores snapshots of our mental context for later reinstatement. We propose a second pathway: the brain's default network sustains the interrupted situation as a background process while other processing continues. In 73 adults listening to interrupted stories during functional brain imaging, the posterior medial cortex sustained a reliable and selective representation of the stages of the interrupted narrative. This background representation changed gradually over narrative time and persisted in a transformed format through silence and through a demanding secondary task. Its persistence predicted how reliably the default network resumed the story and how well listeners later recalled it, revealing complementary hippocampal and cortical pathways to mental continuity.