Date: Friday, September 5,  2025
Time: 12:00pm – 1:00pm
Location: Simons Center Conference room 46-6011 + Zoom [https://mit.zoom.us/j/92816748974]

Speaker: Gwangsu Kim,  Ph.D.
Affiliation: Simons Postdoctoral Fellow, DiCarlo Lab, McGovern Institute, MIT

Talk title: Neural substrate of visual valence in the primate amygdala

Abstract: The primate amygdala is known to encode the valence of sensory stimuli, particularly through conditioning-based associative learning. However, the neural mechanism by which valence is assigned to unconditioned visual inputs—lacking explicit value association—remains unclear. Here, we report that primate amygdala neurons systematically assign valence to unconditioned naturalistic visual inputs without explicit value conditioning. Electrophysiological recordings from the primate amygdala and inferior temporal cortex (IT) during the presentation of 400 novel images revealed that some amygdala neurons exhibit reliable visual tuning comparable to IT neurons. The amygdala responses were predictable using task-optimized models of IT, supporting its role as a subsequent layer in the visual processing hierarchy. Notably, significant subpopulations of visual amygdala neurons jointly encoded valence, with their cross-modal valence tuning linearly predictable from their visual tuning profiles. These findings suggest that the amygdala systematically process valence of unconditioned visual stimuli, alongside its role in associative learning.

Bio: Gwangsu received his BSc (2017) and PhD (2023) in Physics from Korea Advanced Institute of Science and Technology. He joined the MIT McGovern institute in 2024 as a postdoctoral researcher. During his PhD, he studied brain-like functional representations of sensory stimuli in deep neural networks and their underlying computational principles.