visual agnosia

Last reviewed 01/2018

Visual agnosia is the inability to understand the meaning of visual stimuli despite apparently normal vision. There is a loss of recognition of visual percepts.

There are two stages of visual agnosia:

  • apperceptive agnosia:
    • this is more severe and represents an inability to categorise or manipulate the visual percept in any way
    • the patient may be unable to distinguish shape or say if they have seen an object before

  • associative agnosia:
    • this is less severe because a limited understanding of the relevance of a visual object is retained
    • the patient may realise they are looking at a face but be unable to recognise who's face it is (prosopagnosia)