ELSC Seminar Series

To understand why you are reading this abstract, you may recall your past enjoyment of ELSC seminars and your recent consideration of whether to attend this week’s seminar. This exemplifies how our present experiences are linked to relevant past events. In this talk, I will propose our brains achieve this through a process termed “replay”. Originally observed in rodents during navigation tasks, replay involves the rapid reactivation of cell firing patterns related to previous locations, as if binding these locations into an internal model of the environment. I hypothesize that replay could similarly bind episodic events into an internal model of evolving experience. This hypothesis cannot be studied in experiments based on repeated trials, typical of rodent studies, as the neural representations of repeated events are virtually indistinguishable. However, in evolving experiences, like narratives, each event has a unique representation that can be studied in humans. I will present fMRI findings suggesting that, at the boundaries between narrative events, regions of the Default Mode Network reactivate representations of past events that are relevant to each narrative stage. These findings suggest that reactivations act as an online sense-making mechanism that interprets incoming information in light of past experience.