Understanding impaired analysis of faces by patients with probable Alzheimer's disease

The purpose of this study was to analyze the facial recognition skills of patients diagnosed with Probable Alzheimer's Disease (AD). The performance of 181 AD patients was evaluated to address their ability to: analyze visual forms, to discriminate individual faces, and to recognize and name familiar famous faces. The results of the study demonstrate that the ability to analyze visual information is more vulnerable early in dementia than is the ability to discriminate individual faces. The inability to recognize familiar faces among the AD patients was related to impairments of their lexical/semantic system, rather than to a specific defect in facial discrimination. These data are fully consistent with existing models of face processing and recognition, and suggest that the recognition defect in AD is related to the naming component of face recognition, rather than the perceptual component.