Masked Speech Audiometry in Central Deafness

Abstract

Speech tests in the presence of white noise at different S/N ratios were carried out upon normal subjects and patients with a variety of intracranial lesions. In 15 patients with brain stem lesions the masked speech scores were found to be significantly lower than those of normal subjects. In some, the loss was unilateral, in others bilateral. No correlation could be established however with respect to the level or lateralization of the lesion. In a group of 10 patients with temporal lobe lesions the scores from the contralateral ear were consistently and significantly lower than those from the ipsilateral ear: this difference was not present in a group of patients with cortical lesions outside the temporal lobe. No clear evidence of cerebral dominance emerged from the comparison of a group of right-and left-handed normal subjects or patients with unilateral right and left temporal lobe lesions.