The when and what of episodic encoding
Speaker Aya Ben-Yaakov, Research Fellow at MRC Cognition and Brain Science Unit, University of Cambridge.
In striving for experimental control, studies of human episodic memory have focused mainly on encoding of brief, stationary events. Such events, while providing a high degree of control, bear little resemblance to real-life memory and constrain the questions that can be asked. I will demonstrate how use of naturalistic stimuli enables us to address previously unaskable questions, discussing a set of fMRI studies in which we asked when episodic memories are formed. Using film clips as a proxy for real-life memory, we found that hippocampal activity time-locked to the offset of events, but not their onset or duration, is linked to subsequent memory. In a subsequent study we analysed brain activity of over 200 participants who viewed a naturalistic film and found that the hippocampus responded both reliably and specifically to shifts between scenes. Taken together, these results suggest that during encoding of a continuous experience, event boundaries drive hippocampal processing, potentially reflecting the encoding of bound representations to long-term memory. I will discuss how this surprising finding opened a new avenue of research, asking what is encoded in episodic encoding – is each element encoded independently, or is the entire episode encoded as a cohesive unit?
Record link: https://us02web.zoom.us/rec/share/UqzjGMNQmHIurdLhL_2Ob-BBmjCfYWBWxRMPkCoWic8KT-hXWJCBLMDwvwOizFE.NahXnmoKsmd6lVIn (Access code: 8#LhnmE#)