Distraction by auditory novelty. The course and aftermath of novelty and semantic effects.

The unexpected occurrence of an oddball auditory stimulus (novel) among an otherwise repeated stream of sounds (standards) is known to impact negatively on participants’ performance in an unrelated visual task. The present study sought to test new predictions emerging from Parmentier’s (2008) model of distraction by auditory novelty. Participants categorized the direction of visual arrows preceded by a task-irrelevant sound. Two time intervals between distractor and target were tested in separate blocks of trials. Rare auditory novels consisted of the words “left” or “right”, which were either congruent or incongruent with the upcoming target. The data confirmed the slowing of response in the face of a novel (novelty distraction) as well as, on incongruent trials, a further delay due to cross-talk interference between distractor and target (semantic effect). More importantly, and in line with our predictions, the results further showed that (1) the semantic effect, but not novelty distraction, increased with the time interval between distractor and target; and that (2) the production of a response on the first standard trial following a novel trial was slowed if that response required the activation of a recently inhibited network (post-novelty semantic effect). Overall, the data lend support to the view that behavioral distraction by auditory novelty reflects a mosaic of contributors, the effects of which can ripple across trials.