Hemispheric and Directional Asymmetry of Pitch Discrimination

Abstract

The purpose of this article is to report the results of a study that indicate that the ability of the brain's hemispheres to discriminate small changes in pitch is differentially affected by the direction of the change. The two studies discussed used two independent samples. In the first experiment subjects are described as musically sophisticated and in the second experiment subjects are described as musically naive. The task, which was identical in both studies, required subjects to (1) determine if they perceived a change in frequency and if so, (2) to indicate in which ear the change occurred and the direction of the change. In both studies the right ear heard more correct scores when the frequency changes were ascending whereas the left ear heard more correct scores when the frequency changes were descending. In the first experiment this interaction was significant at the .003 level and in the second experiment, although the trend was the same, an acceptable level of significance was not achieved (p = 12).