Effects of leading and trailing tones on frequency discrimination of signal tones

Abstract

The effects of leading and trailing tones (interference tones) on frequency discrimination of a brief tone are investigated and auditory response to the unsteady sounds is discussed. Changes in frequency discrimination were measured as a function of frequency difference between the interference and signal tone, and interval between the two tones (Δt). The results show that frequency discrimination deteriorates as Δt decreases, and the performance is significantly affected by the interference tone especially for Δt less than 20 ms, and they also show that frequency discrimination of test tone accompanied with the interference tones of the same frequency as the test tone is almost the same as in the case without the interference tones. Frequency discrimination becomes worse, however, in the presence of interference tones with the frequency slightly different from the test tone, and when the frequency of the test tone is 1000 Hz, the effect of the interference tone is maximum for the frequency difference of 50 Hz. But frequency discrimination is little affected by interference tones when the difference in frequency between test and interference tones is greater than 100 Hz. The relation between temporal masking and frequency discrimination is discussed.