Lateralization by frequency for repeating sequences of dichotic 400- and 800-Hz tones

Abstract

Subjects [human] made lateralization judgments involving dichotic sequences of 250-ms tones, which alternated in frequency between 400 and 800 Hz, such that when 1 ear received 400 Hz the other ear received 800 Hz, and vice versa. With sequences consisting of 20 dichotic tone pairs there was a strong tendency to lateralize each fused tonal percept toward the ear receiving the 800-Hz signal. In certain subjects the effect also occurred even when the 800-Hz tone was substantially lower in amplitude than the 400-Hz tone, and when it was clearly lesser in loudness. With sequences consisting of only 2 dichotic tone pairs, this lateralization-by-frequency effect was substantially weaker.