Distraction by Auditory Categorical Deviations Is Unrelated to Working Memory Capacity: Further Evidence of a Distinction between Acoustic and Categorical Deviation Effects

Abstract

A rare and unexpected change (or deviation) in the properties of an irrelevant auditory background can disrupt performance of a visual focal task via attentional capture. Although this effect is typically caused by a change in the acoustic properties of the sound, recent evidence has shown that a change in (semantic) category within a sound stream could also disrupt ongoing cognitive activity. The present study aimed to investigate the functional characteristics of this recently discovered categorical deviation effect. In two experiments, an irrelevant sound stream was presented while participants performed visual serial recall. We examined whether working memory capacity (WMC) is associated with susceptibility to distraction by an unexpected change in category within the sound. Acoustically deviating sounds were also presented to compare the categorical and acoustic deviation effects directly. Both experiments revealed that the categorical deviation effect was not correlated with WMC. The expected relationship between WMC and the acoustic deviation effect was observed, but the acoustic and categorical deviation effects were unrelated. Our results constitute new evidence of a distinction between the acoustic and categorical deviation effects despite their apparent similarity. They also suggest that the categorical deviation effect is not underpinned by attentional capture.