Abstract:
A 40-year-old, right-handed female showed cortical deafness and aphasia following a brain stroke. A CT scan showed that a low-density area occupied both of the temporal lobes. In the basal ganglia and thalamus no lesions were observed. Results of audiological examination were as follows. (1) Pure-tone audiometry revealed a mild bilateral hearing loss. An audiogram showed a type of C4 dip. (2) Bekesy audiometry showed that the thresholds were extremely unstable. (3) Speech audiometry showed very poor discrimination scores. (4) Discrimination of musical instruments was remarkably poor. (5) An aural reflex test showed normal responses. (6) The auditory brain-stem response elicited by click stimuli was normal in pattern and latency. (7) Middle latency response was almost normal. Auditory function in the cochlea and the brain stem appeared to be almost intact, but cortical and/or subcortical damage of hearing function was suspected bilaterally. The conclusion from these data is that bilateral partial temporal lobe infarction produced a clinical picture of cortical deafness.