Tracking the misallocation and reallocation of spatial attention towards auditory stimuli

Abstract

Completely ignoring a salient distractor presented concurrently with a target is difficult and sometimes attention is involuntarily attracted to the distractors location (attentional capture). Employing the N2ac component as a marker of attention allocation towards sounds, in this study we investigate the spatio-temporal dynamics of auditory attention across two experiments. Human participants (male and female) performed an auditory search task, where the target was accompanied by a distractor in 2/3rd of the trials. For a distractor more salient than target (Exp. 1), we observe not only a distractor N2ac (indicating attentional capture), but the full chain of attentional dynamics implied by the notion of attentional capture, namely: (a) the distractor captures attention before the target is attended, (b) allocation of attention to the target is delayed by distractor presence, and (c) the target is attended after the distractor. Conversely, for a distractor less salient than the target (Exp. 2), although behavioral interference was present, no attentional capture was observed. Together, these findings reveal two types of spatial-attentional dynamics in the auditory modality (distraction with and without attentional capture). Significance StatementOftentimes, we find it hard to ignore the location of a salient sound that distracts us from our current tasks. Although, a common everyday experience, little is known about how spatial distraction unfolds at the neural level in the auditory modality. Using electrophysiological markers of attention allocations, we report comprehensive evidence of spatial attentional capture by a salient auditory distractor, indicating that attention is first misallocated to the distractor and only afterwards reallocated towards the target. Similar patterns were observed earlier only in vision and their discovery in the auditory modality indicates towards the existence of domain-general spatial attentional dynamics consistent across sensory modalities. Finally, we demonstrate that only a distractor more salient than the target reliably captures attention.