Schedule of Events | Symposia

Generative modeling tools for characterizing human higher visual cortex

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.

Margaret M Henderson¹ (mmhender@cmu.edu), Andrew F Luo¹, Sungjoon Park¹, Michael J Tarr¹, Leila Wehbe¹; ¹Carnegie Mellon University

Characterizing the fine-grained functional organization of human higher visual cortex remains a significant challenge. Traditional neuroimaging experiments are limited in the number of stimuli they can sample, which may bias results toward particular stimulus attributes. In prior work we developed a novel data-driven tool, termed “BrainDiVE” (Luo et al. 2023, NeurIPS), which addresses these challenges by synthesizing images optimized to activate specific brain regions. BrainDiVE leverages pretrained image diffusion models guided by gradients from an image-computable fMRI encoding model. Here, we validated BrainDiVE experimentally by generating images that targeted several functional regions of interest (i.e., images predicted to maximally activate those areas), and showing them to participants in a new human fMRI study. We found that the synthesized images elicited robust and specific responses in the predicted target regions, validating BrainDiVE's ability to capture neural selectivity in human ventral visual cortex. Furthermore, we demonstrated fine-grained experimental control by differentially activating two face-selective regions—the occipital face area (OFA) and fusiform face area (FFA)—suggesting, as reflected in the BrainDiVE images, that they encode distinct aspects of faces. These findings provide new insights into the representational structure of category-selective regions and establish a novel paradigm for targeted exploration of neural selectivity in human visual cortex. More generally, our approach offers a powerful tool for investigating the functional organization of visual cortex at a fine-grained level, exceeding the capabilities of traditional methods across multiple dimensions.

Topic Area: PERCEPTION & ACTION: Vision