Abstract
Cognitive load influences distractibility; distractors are more likely to be processed and slow reaction times during low cognitive load. In contrast, attentional resources are more limited during high cognitive load, limiting our ability to process peripheral stimuli. As a result, reaction times are quicker in the presence of distractors during high cognitive load. We manipulated distractor location to determine whether location differentially influenced the degree of distractibility. Participants (N=36) completed the irrelevant-distractor paradigm. On 80% of trials participants completed a visual search task, where they had to identify whether the target was an 'X' or an 'N'. In the low load condition, non-target stimuli consisted of lower case 'o' letters, whereas in the high load condition, heterogeneous angular letters, with the same dimensions as the target letter were used. In the remaining 20% of trials, a cartoon character appeared in the periphery (above, below, left or right of the visual search array). Reaction times (ms) were recorded on each trial. There was a strong effect of cognitive load, F(1,29) = 124.992, p < .001, η2 = .812, as reaction times were faster during low load than high load. Importantly, the interaction of cognitive load and distractor location was significant, F(1,29) = 39.489, p < .001, η2 = .577. During low load, reaction times increased equally for all distractor locations. In contrast, left distractors speeded reaction times significantly more than did right distractors during high load. We suggest that the attentional spotlight was sufficiently large to encapsulate both the distractor and the visual array during low cognitive load, leading to increased distraction, whereas the attentional spotlight split across the two visual stimuli during high load. Further, executive control is better in the left visual field, which prevents distraction and provides a greater performance benefit.
Meeting abstract presented at VSS 2017