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 that implicated the left fusiform face area (FFA). During passive viewing of faces, face-selective activation was reduced in the left 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 right anterior superior sulcus (aSTS). Within the face network, DPs showed the greatest reduction in functional connectivity between the right aSTS and the left FFA. However, we found no evidence for functional connectivity differences beyond the areas surrounding the face-selective regions, indicating that functional connectivity deficits in DP are mostly confined to the face network. Overall, these results emphasize the role of the left FFA in face recognition deficits, both in local activation and in its connectivity within the face network.