Monetary incentives have only limited effects on auditory distraction: evidence for the automaticity of cross-modal attention capture

The duplex-mechanism account of auditory distraction postulates that two distinct forms of auditory distraction can be distinguished by whether or not they can be cognitively controlled. While the interference-by-process component of auditory distraction is postulated to be automatic and independent of cognitive control, the stimulus-aspecific attention capture by auditory deviants and the stimulus-specific attentional diversion by auditorily presented distractor sentences should be suppressed by increased task engagement. Here we test whether incentive-induced changes in task engagement affect the disruption of serial recall by auditory deviants (Experiment 1) and distractor sentences (Experiment 2). Monetary incentives substantially affected recall performance in both experiments. However, the incentive-induced changes in task engagement had only limited effects on auditory distraction. In Experiment 2, increased task engagement was associated with a small decrease of distraction relative to a quiet condition, but strong effects of auditory distraction on performance persisted in conditions of high task engagement in both experiments. Most importantly, and in contrast to the predictions of the duplex-mechanism account, the effects of stimulus-aspecific attention capture (Experiment 1) and stimulus-specific attentional diversion (Experiment 2) remained unaffected by incentive-induced changes in task engagement. These findings are consistent with an automatic-capture account according to which only the processes responsible for the deliberate memorization of the target items are dependent on controlled mental effort while the attention capture by auditory deviants and the attentional diversion by distractor speech are largely automatic.