Concurrent category-selective neural activity across the ventral occipito-temporal cortex supports a non-hierarchical view of human visual recognition

The human visual system relies on a complex network of regions within the ventral occipito-temporal cortex (VOTC) to recognize various objects, including faces. Traditionally, this network was believed to follow a hierarchical structure, with distinct processing stages that evolve from posterior to anterior cortical areas. To challenge this notion, researchers conducted a study involving 140 participants and captured neural activity from 11,000 recording sites using electrophysiological intracerebral recordings.

The findings revealed that face-selective neural activity exhibiting high-frequency broadband (30-160 Hz) patterns was distributed throughout the VOTC, with a notable right-hemispheric dominance and specific regional peaks of activity. Interestingly, while there was a discernible progression in category-selectivity along the postero-anterior axis of the VOTC, the neural activity was largely synchronous across all regions, ranging from a 100 ms onset to a 450 ms offset.

This concurrent occurrence of category-selective neural activity across the VOTC contradicts the conventional hierarchical model of visual object recognition in the human association cortex. The researchers' observations lend support to alternative models that propose a more non-hierarchical approach to this fundamental brain function.