Auditory Sound Agnosia without Aphasia Following a Right Temporal Lobe Lesion

A 55-year-old right-handed man showed inability to recognize the meaning of nonverbal sounds without impairment of language comprehension after a cerebrovascular accident. His auditory acuity was intact and no other sign of agnosia, apraxia or aphasia was detectable. His errors on a test of sound recognition were acoustic rather than semantic. Brain CT scan showed a small lesion in the posterior part of the right temporal lobe. This case suggests that auditory sound agnosia without language disorder can ensure a lesion confined to the right hemisphere, that the deficit is discriminative rather than associative in nature.