Temporal course of perceived auditory duration

Abstract

A series of experiments explored the temporal course of the perceived duration of an auditory stimulus. A backward recognition masking paradigm was utilized, in which the subject was to determine which of two target durations was presented on a given trial. The target tone was followed, after a variable silent intertone interval, by a masking tone which could assume one of three possible durations. Identification of the long target was found to improve consistently with increases in the intertone interval. In contrast, identification of the short target was as accurate at the short as at the long intertone intervals. Blocking the intertone interval across experimental sessions eliminated these differences between the two target tones. Performance on both the long and the short target tones improved monotonically with increases in the intertone interval. When masking tone duration was randomized within an experimental session, identification of the long (short) target was most accurate with the longer (shorter) masking tone. Blocking the duration of the masking tone across experimental sessions eliminated the effect of the duration of the mask, but did not alter any of the other results. A model, proposed to account for the results, assumes that the percept of target duration grows over time, and can be terminated by the onset of the masking tone. The masking tone also acts to lengthen the perceived duration of the target tone, and this lengthening is a direct function of the duration of the masking tone.

Recognition masking of auditory duration

“…The target tone had a full amplitude duration of either 55 or 85 msec and was presented at either 75 or 81 dB (SPL). The silent lSI that separated the target and mask was 25,45,105,165,205,255, or 500 rnsec; these values were the same as those used by Massaro and Idson (1976), except for the absence, in the present experiment, of a 5-msec lSI and the substitution of a 500-rnsec lSI for the no-mask condition. The mask had a full amplitude duration of 40,70, or 100 rnsec and was presented at either 75 or 81 dB (SPL).…”

“…A third result found by Massaro and Idson (1976) was that the perceived duration of a target sound appeared to increase with increases in the duration of the mask: in the identification experiments, the probability of a response of ' 'long" increased with increases in the mask duration; in the rating experiments, the average rating of the duration of the target increased with increases in the duration of the mask. Target/mask assimilation effects have also been found in studies of pitch and lateralization masking (Hawkins & Presson, 1977;Hawkins, Thomas, Presson, Cozic, & Brookmire, 1974;Kallman Copyright 1986 Psychonomic Society, Inc. to a modification of the auditory memory of the target sound brought about by the presentation of a mask (Kallman & Massaro, 1979).…”

“…There are, however, difficulties with any simple integration-based explanation of the present results. In their experiments on backward duration masking, Massaro and Idson (1976;Idson & Massaro, 1977) used a 5-msec lSI as well as the longer ISIs that we used. With the 5-msec lSI, they found that the perceived duration of the target was much greater than would have been predicted from performance at the longer ISIs.…”

“…Accordingly, performance improved on long-target trials not only because of the diminished effect of the mask on discriminability as lSI increased, but also because the target, on average, was perceived as longer. On short-target trials, increases in the discrirninability of the targets were apparently offset by the perceptual lengthening of the target, which yielded fewer "short" responses (see Massaro & Idson, 1976 Figure 3. Percentages correct as a function of the interstimulus interval on forward-masking (left panels) and backward-masking (right panels) trials.…”

“…After offering evidence that this bias to give "long" responses at the longer ISIs was not due simply to decision processes, Massaro and Idson suggested that the perceived duration of a sound increased with increases in the amount of time spent on its processing; Gol'dburt (1961) also reported results consistent with this conclusion. According to Massaro and Idson (1976), "this change in perceived duration occurs simultaneously with changes in discriminability" (p. 347).…”