M. Jane Collins
John K. Cullen, Jr.
Dept. of Commun. Sci. and Disord., Louisiana State Univ., 163 Music and Dramatic Arts, Baton Rouge, LA 70803
An approach based on signal detection theory was used to measure the stream segregation of tone sequences. Previous research [Dannenbring and Bregman, J. Exp. Psych. Human Percept. Perform. 2, 544--555 (1976)] has shown that stream segregation is highly correlated with the elements in a sequence being perceived as ``overlapped.'' In the present experiment, two classes of sequences were employed. One half of the sequences was composed of tones that physically overlapped, and the remainder of the sequences in the experiment used tones which were physically separated. The sequences were parametrically varied in terms of duration of the sequences and frequency differences of the tones in the sequences. The experimental task required the subject to decide whether or not a sequence was overlapped. Responses to the two classes of sequences were used to calculate measures of discriminability, bias, and criterion. Results using this procedure primarily show significant main effects of frequency difference of the elements in sequences and duration of the sequences; however, no significant interaction of frequency difference and duration was found.