Poster B95, Sunday, March 26, 8:00 – 10:00 am, Pacific Concourse
Depth electrode recording of the amygdala-hippocampal network during mnemonic discrimination of emotional scenes
Jie Zheng1, Rebecca F. Stevenson1, Logan D. Harriger1, Stephanie L. Leal2, Sumeet Vadera1, Michael A. Yassa1, Jack J. Lin1; 1University of California, Irvine, 2University of California, Berkeley
There is accumulating evidence that emotional arousal modulates mnemonic discrimination, the ability to discriminate between similar events or experiences. Results from a high-resolution fMRI study performed by our group suggest that this effect is mediated by interactions between the amygdala (AMY), a region critical for emotional processing, and the hippocampus (HC), which is thought to support mnemonic discrimination via pattern separation. However, higher temporal resolution is needed to characterize the dynamics of HC-AMY interactions. In the current study, we used AMY and HC depth electrode recordings in eight pre-surgical epilepsy patients to examine oscillatory activity during the discrimination of similar emotional and neutral scenes. Using a high-resolution MRI anatomical template coupled with post-implantation MRI scans, we were able to localize the depth electrodes within HC and AMY subregions. We analyzed theta (3-8 Hz) and gamma (70-150 Hz) power as well as theta coherence and found coordinated activity across HC and AMY that was modulated by memory and emotion. These results contribute to our growing understanding of the AMY-HC network and of how circuit-level interactions within this network influence the encoding and retrieval of episodic memory.
Topic Area: LONG-TERM MEMORY: Episodic