The historical roots and recurring issues of neurobiological studies of face perception.

Evidence concerning the neurobiological basis of face perception is converging from three directions. First, there are studies of neurological patients who present with specific difficulties in the recognition of familiar faces. Second, there are neuropsychological studies of face perception in normal people which identify some of the psychological mechanisms involved in face perception. Thirdly, there are neurophysiological studies in non-human primates which point to specific neural mechanisms which selectively process faces. A review of the literature from these three distinct areas of research suggests that there may indeed be something quite specific about the neural mechanisms selectively processing faces. The evidence from cognitive neuropsychology indicating a hierarchy of stages involved in visual processing and visual recognition suggests that where there is difficulty in recognizing familiar faces resulting from brain damage, the precise nature of the difficulty may depend upon which stage or stages in this hierarchy have been most affected. This in turn will reflect the particular localisation of the lesions that have been sustained.