Distributed network flows generate localized category selectivity in human visual cortex
Fig 6
Distributed activity flows account for the majority of localized selectivity to faces.
All figure specifications follow Fig 5. (A) The activity flow procedure mapping activations to face categories, projected onto cortical schematics (right hemisphere). Right FFA/pSTS was the held-out target complex. (B) The connectivity fingerprint [13,15] of the right FFA/pSTS via whole-cortex rsFC (black lines). Radial lines: source regions connected to the FFA/pSTS, clustered by functional network assignments [25] (colored per legend and Fig 3C). (C) Face category selectivity exhibited by the right FFA/pSTS. Significant t-statistics are indicated with an asterisk (p<0.00001; see Methods). (D) Estimated contribution of distributed activity flow processes to face selectivity exhibited by the right FFA/pSTS. (E) Activity flows (as in A step 3) of each source region contributing to the mapping of FFA/pSTS responses to face images. VIS2 regions contributed most to the FFA/pSTS mapped activation magnitude to faces. (F) Variance explained by each network-restricted activity flow model (unmixed partial R2 via dominance analysis; Methods) of the right FFA/pSTS’ response profile. VIS2 accounted for the most variance, altogether suggesting that activity flowing over VIS2 regions represents a general network coding mechanism for FFA/pSTS processing. DAN and DMN regions also accounted for a nontrivial amount of variance at the response-profile level suggesting that, across diverse cognitive domains, FFA/pSTS processing is impacted by activity flowing over DAN and DMN regions, in addition to VIS2 (in the face-specific case).