Auditory Induction of Discrete Tones in Signal Detection Tasks.

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 non-alternating 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. Results indicated that auditory induction is a general factor influencing auditory perception and can be demonstrated either for discrete as well as continuous presentation of sounds. While induction of missing sounds can be beneficial, especially in speech perception, auditory induction can also impair perceptual performance, particularly in monitoring nonspeech sounds for faint signals. Finally, auditory-induction effects can be distinguished from peripheral-masking effects, and although a relation between auditory induction and central masking cannot be ruled out, induction and masking appear to be separate, independent factors, one largely central, and other largely peripheral in nature.