Abstract
Are segregated and independent psychological and neural mechanisms required for the recognition of different visual inputs such as faces and common objects? One source of evidence to address this question comes from studying associations versus dissociations of function in individuals with impairments in visual recognition. Here, we examine whether an impairment in face recognition is accompanied by a deficit in object recognition in individuals with congenital prosopagnosia (CP), an apparently lifelong problem that occurs without brain damage (on conventional MRI) and with normal vision and intellect. We present survey data from an analysis of 712 cases of adults with CP dating from 1976 to the present time (117 papers) and of 42 cases of children with CP. Of those reports where there are sufficient data to adjudicate this issue (i.e. testing of both faces and object perception completed and adequate dependent measures), 91.7% of CP individuals have both prosopagnosia and visual object agnosia, either mild (26.4%) or more severe (65.3%). The remaining 8.3% of individuals do not have an obvious object recognition deficit. We propose a single mechanism account that may explain both the preponderance of associations and the small set of dissociations within the context of a single mechanism, and we offer suggestions for research that would permit further evaluation of the relationship between object agnosia and prosopagnosia.
Meeting abstract presented at VSS 2017