Associative visual agnosia: a case study.

Abstract

This report describes a case of associative visual agnosia caused by a left sided, cortico-subcortical, inferior temporo-occipital infarction. Performance on visual perceptual tests was normal, while it was defective on visual classification tasks. Visual agnosia was interpreted as a visuo-verbal disconnection plus a categorization deficit for visual meaningful common stimuli. The left occipito-temporal lesion disrupted the visual classification process and prevented access of visual information to language areas and limbic system. The absence of right hemispheric lesion accounted for the normal recognition of familiar faces and other unique individual stimuli such as familiar places, whose recognition occurs through contextual evocation.