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Title: Searching through functional space reveals distributed visual, auditory, and semantic coding in the human brain
The extent to which brain functions are localized or distributed is a foundational question in neuroscience. In the human brain, common fMRI methods such as cluster correction, atlas parcellation, and anatomical searchlight are biased by design toward finding localized representations. Here we introduce the functional searchlight approach as an alternative to anatomical searchlight analysis, the most commonly used exploratory multivariate fMRI technique. Functional searchlight removes any anatomical bias by grouping voxels based only on functional similarity and ignoring anatomical proximity. We report evidence that visual and auditory features from deep neural networks and semantic features from a natural language processing model, as well as object representations, are more widely distributed across the brain than previously acknowledged and that functional searchlight can improve model-based similarity and decoding accuracy. This approach provides a new way to evaluate and constrain computational models with brain activity and pushes our understanding of human brain function further along the spectrum from strict modularity toward distributed representation.  more » « less
Award ID(s):
1839308
PAR ID:
10300499
Author(s) / Creator(s):
; ; ; ;
Editor(s):
Jbabdi, Saad
Date Published:
Journal Name:
PLOS Computational Biology
Volume:
16
Issue:
12
ISSN:
1553-7358
Page Range / eLocation ID:
e1008457
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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