Category specificity in object agnosia: preservation of sensorimotor experiences related to objects

We report a case of semantic agnosia, characterized by category specificity . Object recognition, mainly involving visual representation, was severely impaired, whereas object recognition involving both visual and sensorimotor representations, was relatively well preserved. His ability to recognize g estures and produce appropriate gestural responses to objects was remarkabl e. These two factors lead the authors to form a hypothesis, in an attempt t o explain the mechanisms involved in object recognition. It has been argued that manipulation of an object may give access to a certain amount of know ledge about it, and that preservation of sensorimotor experiences of object s might be important in recognizing some of them. This could account for th e category specificity, described in object agnosia. (C) 1998 Elsevier Scie nce Ltd. All rights reserved.