Dichotic perception of AM and FM signals

• Published in: The Journal of the Acoustical Society of America 1999-02, Vol.105 (2_Supplement), p.1343-1343
• Main Authors: Ozimek, E., Konieczny, J., Wicher, A.
• Format: Article
• Language: English
• ISSN: 0001-4966; 1520-8524
• DOI: 10.1121/1.426369

The study deals with the binaurally perceived modulation depth (mp) of amplitude-modulated signals (Exp. I) and binaurally perceived frequency deviation (Δfp) of frequency-modulated signals (Exp. II), for their diotic and dichotic perception. Various combinations of modulation depth (m) and frequency deviation (Δf) at the left and right ear were used. It was found that when the interaural difference in modulation depth (Δm=ml−mr) or interaural difference in frequency deviation (ΔΔf=Δfl−Δfr) were equal to zero (i.e., diotic perception), the binaurally perceived modulation depth or binaurally perceived frequency deviation were the same as those in monaural perception. For sufficiently small Δm or ΔΔf, the perceived modulation depth, or frequency deviation, approximated the mean of the magnitudes presented to the left and the right ear. However, for large interaural differences in Δm or ΔΔf, the binaurally perceived quantities were lower than their arithmetic means, and showed nonlinear trends. Comparison of the perceived modulation depths determined in the experiment and those calculated under the assumption of the linear summation of AM signals from the left and the right ear are also discussed.