AbstractsBiology & Animal Science

What brain regions underlie retrieval from episodic memory? The bulk of research addressing this question has relied upon laboratory-based recognition memory. Another, less dominant tradition has employed autobiographical methods, whereby people recall events from their lifetime, often after being cued with words or pictures. Previous research comparing regions underlying successful memory retrieval between these two methodological approaches has shown mixed results. To examine the neural processes underlying recognition memory for materials encountered in the laboratory and autobiographical memory, we conducted a within-subject study using fMRI. We showed participants indoor and outdoor scenes under two types of instructions: In the lab-based recognition condition we asked participants to report whether they remembered the scene from the prior study phase. In the autobiographical condition, participants were asked to report whether the scene reminded them of a specific event in their lives. We compared the BOLD activity of successful retrieval of lab-based recognition memory (hits) to the reported successful retrieval of autobiographical memory. We found many regions differentially activated during the two tasks. Critically, autobiographical retrieval activated the default mode network more whereas recognition hits engaged two subnetworks of the frontoparietal network more. The finding of areas differentially activated during the two types of memory retrieval suggests that successful retrieval in the form of recognition of recently-studied items and successful retrieval in the form of stimulus-evoked autobiographical memories engage different processes and are dissociable.