Schedule of Events | Symposia

Examining Fear Conditioning/Extinction and the Role of the Amygdala Using High Resolution Neuroimaging

Poster Session D - Monday, March 31, 2025, 8:00 – 10:00 am EDT, Back Bay Ballroom/Republic Ballroom

Olivia Cook¹, Karisa Hunt¹, Brendan Depue¹; ¹University of Louisville

Neuroimaging literature focused on fear conditioning and extinction is constrained to spatial resolution of fMRI. This limitation has posed significant challenges to understanding the contribution of the amygdala’s core nuclei with consistency and precision. Recent advancements in neuroimaging technology have begun to address these challenges by enabling higher spatial resolution and accurate fine parcellation of the amygdala; however, the application of high-resolution imaging and amygdala parcellation maps specifically to fear conditioning and extinction paradigms remains largely unexplored. This study used high resolution functional magnetic resonance imaging (hrfMRI) combined with ultra-high resolution (7T) amygdala parcellation maps to explore fear learning and extinction in participants with varying levels of self-reported anxiety to provide new insights into the precise neural mechanisms underlying fear extinction, specifically within the amygdala. During fear acquisition when comparing fear and neutral stimuli, the fear condition showed increased activity in the central nucleus of the amygdala (CE), the dorsal anterior cingulate cortex (dACC), and the anterior insula, as well as decreased activity in the ventral medial prefrontal cortex (vmPFC). There was also increased connectivity between the dACC and the basolateral amygdala (BLA) and decreased connectivity between the vmPFC and CE. In extinction, there were no significant differences in activity or connectivity between fear and neutral. The results support findings from rodent literature that have detailed amygdala activity during fear acquisition and extinction. The output region of the amygdala (CE) appears to be modulated by the vmPFC to inhibit fear responses during extinction similarly to the processing of neutral stimuli.

Topic Area: EMOTION & SOCIAL: Emotion-cognition interactions