ABSTRACT
How do we remember emotional events? While emotion often leads to vivid recollection, the precision of emotional memories can be degraded, especially when discriminating among overlapping experiences in memory (i.e. pattern separation). Communication between the amygdala and the hippocampus has been proposed to support emotional memory but the exact neural mechanisms are not well understood. Here, we used intracranial depth electrode recordings in pre-surgical epilepsy patients to show that successful pattern separation of emotional stimuli is associated with theta band (3-7 Hz)-coordinated bidirectional interactions between the amygdala and the hippocampus. In contrast, we show that overgeneralization is associated with alpha band (7-13 Hz)-coordinated unidirectional influence from the amygdala to the hippocampus. These findings imply that alpha band synchrony may trigger overgeneralization of similar emotional events via amygdala-hippocampal directional coupling, which suggests a target for the treatment of psychiatric conditions such as post-traumatic stress disorder, where aversive memories are often overgeneralized.
AUTHORS
Jie Zheng
Rebecca F. Stevenson
Bryce A. Mander
Lilit Mnatsakanyan
Frank P. K. Hsu
Sumeet Vadera
Robert T. Knight
Michael A. Yassa
Jack J. Lin
Date: 2018