Perceptual heterogeneity in developmental prosopagnosia: The role of the right OFA.

Individuals with lifelong face recognition impairment, developmental prosopagnosia (DP), provide a unique testbed for understanding the neural mechanisms of face recognition. Although the right occipital face area (OFA) and right fusiform face area (FFA) are critical for face processing, studies examining their functionality in DP have been inconclusive. Two barriers that have prevented the development of a neural theory of DP are behavioural heterogeneity and limited sample sizes. Using one of the largest samples of DPs collected to examine OFA/FFA function, we tested whether face selectivity in the OFA and FFA relates to individual differences in perceptual impairment in 34 DPs. Face perception, measured using two face matching tasks, was significantly correlated with face selectivity in the right OFA and FFA in DPs. Then, using feature-specific tasks to measure perception of the eye and mouth regions separately, right OFA selectivity was found to be specific to perception of the eye region. The results are the first to connect the right OFA to eye perception deficits in DP, and one of the few studies to demonstrate the neural underpinnings of DP behavioural heterogeneity. More broadly, these findings support the view that the right OFA is specialized for extracting visual information from the eye region.