Schedule of Events | Symposia

Hierarchical prefrontal contributions to perceptual decision-making

Poster Session F - Tuesday, April 1, 2025, 8:00 – 10:00 am EDT, Back Bay Ballroom/Republic Ballroom
Also presenting in Data Blitz Session 3 - Saturday, March 29, 2025, 10:30 am – 12:00 pm EDT, Constitution A.

Xinxu Shen¹ (tul04056@temple.edu), Ioannis Pappas², Sirawaj Itthipuripat³, Ruedeerat Keerativittayayut⁴, Chayanon Pamarapa⁴, Chaipat Chunharas⁵, Ian Ballars¹; ¹University of California, Riverside, ²University of Southern California, ³King's Mongkut University of Technology Thonburi, ⁴Chulabhorn Royal Academy, ⁵Chulalongkorn University

In visual decision-making, both high-level semantic information and low-level visual properties influence choice. However, the strong correlation between these low and high-level features in natural stimuli makes their contributions challenging to isolate. To address this, we used a deep neural network to design a stimulus set that decorrelates these properties. In the task, participants judged the similarity between a root image and two alternatives, differing in their low- and high-level similarities to the root image. Behaviorally, participants were sensitive to high-level similarity, but also showed an additive effect of low-level similarity. Participants were around 20% more likely to select an image when both low- and high-level information agreed on its similarity than when they conflicted. Neuroimaging results showed that activation in the middle frontal gyrus (MFG) increased with both high- and low-level visual similarity. Strikingly, we observed an anterior-posterior gradient within the MFG, with anterior regions linked to higher-level similarity and posterior regions to lower-level similarity. These results showed that the hierarchical organization of prefrontal cortex in encoding visual information mirrors the hierarchy of visual processing in ventrotemporal cortex. At choice, the ventromedial prefrontal cortex (vmPFC) represented the high-level similarity between the chosen image and the root, mirroring its role in representing the subjective value of choices. These findings expand our understanding of role vmPFC beyond traditional value-based decision-making to include representation of decision variables in any domain where options are compared. Together, the results suggest that the brain integrates low- and high-level visual features hierarchically to support perceptual decision-making.

Topic Area: PERCEPTION & ACTION: Vision