Mental Deafness

Mental deafness, characterized by the inability to recognize sounds heard (to distinguish human voices from animal voices, to recognize various noises, etc.) and by impaired sound memory. It is observed in certain cases of lesions of the outer surface of both temporal lobes. It is often combined with word deafness, i.e., the inability of patients to understand speech addressed to them (see Aphasia), and with complete bilateral lesions of the temporal lobes—with cortical deafness, i.e., with a complete loss of auditory sensations. Some assume that auditory representations are localized in the cortex separately from auditory perceptions; the cortical areas for both do not fully coincide.