Left hemisphere abnormalities in face-selective activation and functional connectivity in developmental prosopagnosia

Developmental prosopagnosia (DP) provides a unique opportunity for identifying neural mechanisms that are necessary for normal face recognition, yet the neural basis of DP remains unresolved. We conducted an extensive fMRI investigation of the functional activation and connectivity of ventral and lateral face-selective regions in DP and expanded the analysis to include connections between this face-selective network and all other cortical regions. From a large sample of DPs (N=34) and controls (N=23), we found neural differences in DPs in both modalities, although the analyses implicated different regions of the face network. During passive viewing of faces, face-selective activation was reduced in the left fusiform face area (FFA) and left occipital face area (OFA). During rest, overall functional connectivity within the face network was reduced in DPs, with the largest reductions involving the bilateral aSTS regions. Within the face network, DPs showed the greatest reduction in functional connectivity between the left pSTS and left aSTS. Although the whole-brain analysis showed that functional connectivity deficits of the aSTS extended into the lateral temporal cortex more broadly, functional connectivity differences in DP were primarily confined to the face network. Overall, these results emphasize the importance of the left FFA for normal face recognition ability and reveal functional connectivity deficits in DP in regions associated with person naming and semantic information retrieval.