A dual contribution to the involuntary semantic processing of unexpected spoken words.

Sounds are a major cause of distraction. Unexpected to-be-ignored auditory stimuli presented in the context of an otherwise repetitive acoustic background ineluctably break through selective attention and distract people from an unrelated visual task (deviance distraction). This involuntary capture of attention by deviant sounds has been hypothesized to trigger their semantic appraisal and, in some circumstances, interfere with ongoing performance, but it remains unclear how such processing compares with the automatic processing of distractors in classic interference tasks (e.g., Stroop, flanker, Simon tasks). Using a cross-modal oddball task, we assessed the involuntary semantic processing of deviant sounds in the presence and absence of deviance distraction. The results revealed that some involuntary semantic analysis of spoken distractors occurs in the absence of deviance distraction but that this processing is significantly greater in its presence. We conclude that the automatic processing of spoken distractors reflects 2 contributions, one that is contingent upon deviance distraction and one that is independent from it.