Definition of agnosia in US English:



  • Inability to interpret sensations and hence to recognize things, typically as a result of brain damage.

    ‘visual agnosia’
    • ‘The cognitive disorder in Huntington's disease is considered a ‘subcortical’ syndrome and usually lacks features such as aphasia, amnesia, or agnosia that are associated with dementia of the Aizheimer's type.’
    • ‘Edward DeHaan and his colleagues describe covert recognition in prosopagnosia, another category-specific agnosia in which faces cannot be visually recognized.’
    • ‘Colour agnosia sometimes manifests in seeing colour without the recognition of the colours of individual objects.’
    • ‘Dementia is chronic and progressive, and it is characterized by the gradual onset of impaired memory and deficits in two or more areas of cognition, such as anomia, agnosia or apraxia.’
    • ‘This is a neurological syndrome called visual form agnosia, which results from damage localized to both temporal lobes, leaving primary visual cortex and the parietal lobes intact.’


Early 20th century: coined in German from Greek agnōsia ‘ignorance’.