2022/05/09 by Yongpeng Duan, Duan, Y., Jinxin Zhan +7 · 1 citation
Neuroscience · #FOS: Biological sciences #Face Recognition and Perception #Neural dynamics and brain function #Neurons and Cognition (q-bio.NC) #Visual perception and processing mechanisms
paper · pdf · doi:10.48550/arxiv.2205.04393
openalex publication_date 2022/05/09 · openalex created_date 2023/02/12 · openalex updated_date 2026/07/28
To interpret our surroundings, the brain uses a visual categorization process. Current theories and models suggest that this process comprises a hierarchy of different computations that transforms complex, high-dimensional inputs into lower-dimensional representations (i.e. manifolds) in support of multiple categorization behaviors. Here, we tested this hypothesis by analyzing these transformations reflected in dynamic MEG source activity while individual participants actively categorized the same stimuli according to different tasks: face expression, face gender, pedestrian gender, vehicle type. Results reveal three transformation stages guided by pre-frontal cortex. At Stage 1 (high-dimensional, 50-120ms), occipital sources represent both task-relevant and task-irrelevant stimulus features; task-relevant features advance into higher ventral/dorsal regions whereas task-irrelevant features halt at the occipital-temporal junction. At Stage 2 (121-150ms), stimulus feature representations reduce to lower-dimensional manifolds, which then transform into the task-relevant features underlying categorization behavior over Stage 3 (161-350ms).