Lateralization of Filtered Clicks

Abstract

Lateralization of brief clicks was studied while the frequency content of the clicks was altered by filtering. The subject was asked to discriminate a centered image, a pair of identical clicks that arrived simultaneously at the two headphones, from a displaced image, a pair of identical clicks in which the click to the left ear was slightly delayed. The discrimination deteriorated as the high-pass cutoffs of the clicks increase beyond 1000 Hz and was largely unaffected by low-pass filtering. Masking with high- and low-pass noise showed that low-pass noise severely disrupted the lateralization of the high-passed clicks, but the high-pass noise produced no disruption of the lateralization of the low-passed clicks. Thus, our results showed that the information crucial for lateralization occurred in the frequency range below 1000 Hz. [Research was supported by the National Institutes of Health, Publich Health Service, U. S. Department of Health, Education, and Welfare.]