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Paper Detail

Paper: PS-2A.54
Session: Poster Session 2A
Location: H Lichthof
Session Time: Sunday, September 15, 17:15 - 20:15
Presentation Time:Sunday, September 15, 17:15 - 20:15
Presentation: Poster
Publication: 2019 Conference on Cognitive Computational Neuroscience, 13-16 September 2019, Berlin, Germany
Paper Title: Evidence for Visual Representation of Numerosity in Natural Scenes
Manuscript:  Click here to view manuscript
License: Creative Commons License
This work is licensed under a Creative Commons Attribution 3.0 Unported License.
Authors: Maggie Mae Mell, Ghislain St-Yves, Medical University of South Carolina, United States; Emily Allen, Yihan Wu, Kendrick Kay, University of Minnesota, United States; Thomas Naselaris, Medical University of South Carolina, United States
Abstract: In visual cortex of human and non-human primates, high-level visual areas near intraparietal sulcus have been shown to explicitly encode the number of objects in visual displays. To date, evidence for this numerosity code has come from experiments that use simple dot-like visual stimuli, raising the question of whether the numerosity code persists during perception of natural scenes. Here, we assessed evidence for a numerosity code in high-resolution fMRI measurements of responses to thousands of natural scenes in 8 human subjects. We constructed an encoding model that predicted voxelwise responses as a function of local object counts in each natural scene. Our model was able to accurately predict voxelwise activity in visual cortex. To test if local object counts were acting as a proxy for simple low-level image features, we constructed voxelwise encoding models based on Gabor wavelet filtering of the natural scenes. For voxels in anterior visual cortex, the numerosity encoding model generated more accurate predictions than the Gabor model. Our results offer evidence for a numerosity code in anterior visual cortex during natural scene stimulation, and suggest that numerosity may be a key higher-order feature that is extracted by the brain during perception of natural scenes.