Susceptibility to the effects of delayed auditory feedback

Abstract

Speech performance deteriorates if a delay is introduced between the time when speakers speak a sound and when they hear it (DAF). Most disturbance occurs when speech is delayed by about 200 msec. Not all speakers are equally susceptible to the effects of DAF. The hypothesis examined here is that deterioration in performing a serially organized behavior (such as speech)occurs when a rhythmic event goes on concurrent with but out of synchrony with the activity. Different susceptibility to the effects of DAF can be accounted for by this hypothesis because the out-of-synchrony signal would differ in loudness, depending on the amount by which speakers raise their voices under DAF. Two experiments are reported which are consistent with this hypothesis. In Experiment 1, it is shown that changes in voice level brought about by voluntary or electronic means increase the disturbance observed. In Experiment 2, it is shown that the out-of-synchrony signal does not have to be speech to produce problems for speech control, because equivalent disruption occurs when a nonspeech signal at the same level as the speech is substituted for the delayed speech sound. © 1984 Psychonomic Society, Inc.