Abstract
People with developmental prosopagnosia (DP) show considerable behavioral and neural heterogeneity, but no links between behavioral and neural measures within DP have been reported. Similar to previous reports, comparison between 18 DPs and 18 controls showed DPs had reduced gray matter intensity in temporal cortex. In addition, DPs had reductions in bilateral inferior frontal cortex, bilateral amygdala, left lateral inferior occipital cortex, and right hippocampus. To examine behavioral differences within the DPs, we assessed their perception of identity, sex, age, race, anger, trustworthiness, eye position, and head viewpoint with sorting tasks. Cluster analysis of these results suggested the DPs could be divided into a group that had normal perception of sex, age, race, anger, and trustworthiness (Type I) and another with impaired perception of these aspects (Type II). Compared with Type II DPs (n = 7), Type I DPs (n = 10) had reduced gray matter intensity in the vicinity of inferior frontal gyrus bilaterally and right lateral inferior occipital cortex and increased gray matter intensity around bilateral hippocampus (uncorrected). Because of the difficulty of establishing a clear division between different types, we computed a perception index for each DP based on the five CFPT tests that differed between Type I and Type II DPs. A multiple regression analysis with the perception index and gray matter intensity found results consistent with our comparison between the two types of DP, with positive correlations for inferior frontal gyrus bilaterally and right lateral inferior occipital cortex, as well as negative correlations for hippocampus bilaterally. In summary, our results indicated that DPs have reduced gray matter in temporal lobe and other areas. In addition, several areas within the DP group showed an association between gray matter and non-identity face perception.
Meeting abstract presented at VSS 2016