Poster Presentation

Contributed Talk Session: Wednesday, August 5, 10:15 – 11:15 am, Skirball Theater
Poster D in Poster Session D: Wednesday, August 5, 2:00 – 3:45 pm, Kimmel Center, Shorin & Rosenthal Rooms

Hyperalignment Reveals Shared Information in Monkeys’ Idiosyncratic Fine-Grained Movie fMRI Patterns

Yuqi Zhang¹, Haiyan Wang², Qi Zhu³, Xiaolian Li⁴, Jane Han¹, Guo Jiahui⁵, Won Mok Shim⁶, Royoung Kim⁶, Maria Gobbini⁷, James Haxby¹, Ma Feilong⁸, Wim Vanduffel⁴; ¹Dartmouth College, ²Institute of Automation, Chinese Academy of Sciences, ³INSERM, CEA, Université Paris-Saclay, NeuroSpin Center, ⁴KU Leuven, ⁵University of Texas at Dallas, ⁶Sungkyunkwan University, ⁷University of Bologna, ⁸University of South Carolina

Presenter: Yuqi Zhang

Hyperalignment (HA) maps individual brain activity into a shared high-dimensional representational space, allowing finer cross-subject comparison than anatomical alignment. Although HA has been widely used in humans, its application in non-human primates remains limited. Here, we applied HA to fMRI data from 12 rhesus monkeys watching Monkey Kingdom. We used the first half of the movie to build a common template and to estimate individual transformation matrices and evaluated performance on the second half. HA improved inter-subject correlation, especially in occipital, temporal, and lateral prefrontal cortex, and increased between-subject movie timepoint classification accuracy by about 80% relative to anatomical alignment. HA also enabled prediction of idiosyncratic functional topographies from other monkeys’ movie-watching and localizer data. Applying the same framework to 24 humans watching the same movie showed similar results. Together, these findings show that HA supports robust cross-subject alignment of fine-grained functional organization in both monkeys and humans.

Topic Area: Methods, Tools, Theory & Neural Coding