A Binaural Integration Test

Abstract

In recent years, disorders involving the central auditory pathways have been investigated using distorted speech material. The methods have included binaural integration tests in which different parts of the same message are presented to the two ears. When investigating the effect of different central pathologies on this integration it is necessary to know the range of variation that can occur in normal subjects.

The present study examines the effect of presenting speech to one ear at a level below the threshold of intelligibility, while the same message is presented to the other ear after filtration. A high pass filter is used on the assumption that a message presented to the other ear below the threshold of intelligibility provides mainly low frequency information.

The discrimination score for both monosyllabic and sentence material is measured for normal subjects under the conditions: (a) filtered; (b) unfiltered; (c) filtered and unfiltered presented binaurally. The range of increase in discrimination score produced on binaural presentation is found for normal subjects and the use of this test for investigating the problems of patients with central pathologies is discussed.

Key Words:

• Binaural hearing
• Modification of speech audiometry
• Detection of central auditory disorders