Auditory induction of discrete tones in signal detection tasks

Abstract

Auditory induction is the apparent continuation of a fainter sound when alternated rapidly with a more intense interrupting sound. In the present study, induction of discrete (nonalterhating) tones by "contextual" tones was examined in three experiments using signal detection methods. Listeners were asked to detect pure tone signals of constant, rising, or falling frequency embedded in noise bursts. The noise bursts were preceded and followed by contextual tones that were designed to produce a constant or changing frequency context. The results of the first two experiments showed that detection of "in-context" signals (e.g., a rising-frequency signal in a rising-frequency context) was associated with an increased false-alarm rate and lowered sensitivity, as compared with "out-of-context" signals (e.g., a falling-frequency signal in a rising-frequency context). To examine the possible influence of peripheral masking, a third experiment was conducted in which signals and contextual tones were presented to different ears. The same pattern of selective contextual impairment of detection performance was obtained. The results indicated that auditory induction can occur with discrete presentation of tones: the contextual tones are perceived as continuing through the noise bursts, and this illusion degrades detection performance. However, the effect occurs only when a signal to be detected is consistent with its context. The results suggest that auditory induction and peripheral masking are independent processes that can cumulatively degrade detection performance with nonspeech sounds. © 1984 Psychonomic Society, Inc.