Abstract
Secondary information presented during a primary task has been repeatedly demonstrated to impair primary task performance. These distraction impairments may be a result of decrements to foveated visual attention, as reflected by failures to detect changes at fixation or recall of fixated objects (McCarley et al., 2004; Strayer et al., 2007). Previous research characterizing distracted visual processing has typically utilized complex and applied scenarios, which directs participants to prioritize their fixations to the center of the display/environment as opposed to the general visual field (e.g., Strayer & Drews, 2007). In four experiments, we aimed to evaluate changes in oculomotor behavior associated with the presence of secondary task information under controlled conditions. The primary task was a visual search task for an oriented target T among distractors Ls (50 & 80 objects); the secondary task was an irrelevant word presented on a heads-up display for 2000ms (compared to search without a secondary task). Participants were instructed that the secondary visual presentation was irrelevant to the search task. The experimental manipulations were overall distraction, masked onset of secondary information, primary information was spatially separated from secondary information, and modality of secondary information (auditory/visual). Overall, we replicated previous studies reporting a cost when search occurred concurrently with a secondary display (Lewis & Neider 2019). These costs were associated with increased fixation durations and initial saccade latencies. No differences occurred in the number of fixations, target verification times, and spatial distribution of fixations (i.e., a contrast to more applied research in the driving domain). The results indicated that secondary task distraction in visual search induces impairments in deployment of attentional processing at fixation, as opposed to an interference in fixated target perception or the constriction of gaze typically associated with applied contexts.