The categorical deviation effect may be underpinned by attentional capture: Preliminary evidence from the incidental recognition of distracters

 The performance of a visual focal task is appreciably disrupted by an unexpected change (or deviation) in the properties of a task irrelevant auditory background. A vast amount of evidence suggests that a change in the acoustic properties of sound disrupts performance via attentional capture. However, an emerging body of evidence suggests that the disruption of task performance by a change in semantic category within a stream of sounds does not behave the same and is therefore not produced by attentional capture. This preliminary study aimed to further investigate whether the disruption produced by a categorical deviant was underpinned by attentional capture. In a single experiment, participants were presented with an irrelevant sound stream while they memorized a categorized list for free recall. We examined whether free recall performance was disrupted by an unexpected change in category within the sound and later investigated, via a surprise recognition test, whether participants had superior memory for deviant items as compared to items from the same positions in control sequences. Results revealed that the categorical deviation effect manifested in poorer free recall performance. Additionally, post-study, participants demonstrated better recognition memory for deviant items compared to control items. On the assumption that explicit recognition requires attentional encoding of deviant items, our results yield evidence that the categorical deviation effect may indeed be produced via attentional capture.