Visual Form Agnosia

FOR almost a century, visual agnosia, conventionally defined as seeing without recognition, has been demonstrated and investigated. Bona fide clinical cases are rare and most theoretical explanations of the mechanisms underlying visual agnosia have been tailored to the findings of an individual patient. The following case was studied in the Aphasia Research Unit of the Boston Veterans Administration Hospital. During this time the visual disturbance was investigated in the laboratory of R. Efron who has reported his findings in detail.1(His data support the view that this patient has a unique defect in visual shape form perception. His paper deals with this patient's problem in terms of the philosophical, definitional, and methodological implications of the disorder. The primary concern is to show that the cognitive defect is a perceptual one and that all the salient features of the recognition disturbance can be accounted for by a profound defect in