Recognition and naming of famous faces in Alzheimer's disease: a cognitive analysis.

A Famous Faces Test designed to assess face recognition, spontaneous naming, verbal identification of un-named faces, and cued naming using semantic and phonetic cues was administered to 22 patients with dementia of Alzheimer type (DAT) and 25 matched controls. The DAT patients were significantly impaired in all test conditions with evidence of a temporal gradient for recognition, identification and naming with phonemic cues, but not for spontaneous naming or naming with semantic cues. Analysis of the effects of disease severity showed that performance in all five conditions of the test declined with increasing disease severity, but this did not reach significance for recognition or for naming with phonemic cues. The DAT patients identified and named a significantly smaller proportion of the faces that they recognized than did the controls, and at no stage was identification significantly better than spontaneous naming. These findings indicate that the primary deficit was not one of name access, but an actual loss of stored knowledge about the person represented. In keeping with this observation, semantic cueing did not aid naming. These findings are discussed in the context of contemporary cognitive models of face processing.