Attentional capture by motion onsets is modulated by perceptual load

Abstract

The onset of motion captures attention during visual search even if the motion is not task relevant, which suggests that motion onsets capture attention in a stimulus-driven manner. However, we have recently shown that stimulus-driven attentional capture by abruptly appearing objects is attenuated under conditions of high perceptual load. In the present study, we examined the influence of perceptual load on attentional capture by another type of dynamic stimulus: the onset of motion. Participants searched for a target letter through briefly presented low-and high-load displays. On each trial, two irrelevant flankers also appeared, one with a motion onset and one that was static. Flankers defined by a motion onset captured attention in the low-load but not in the high-load displays. This modulation of capture in high-load displays was not the result of overall lengthening of reaction times (RTs) in this condition, since search for a single low-contrast target lengthened RTs but did not influence capture. These results, together with those of previous studies, suggest that perceptual load can modulate attentional capture by dynamic stimuli.

Finding a link between guided search and perceptual load theory

“…The results supported a perceptual load account of selective attention; and yet, a subsequent study-conducted in the same laboratory and using the same paradigm-showed that task-context could bias the results to support either perceptual load theory as postulated, or could show that salient distractors were fully processed under high perceptual load (Biggs & Gibson, 2010). Perceptual load has also been shown to modulate interference by salient abrupt onset stimuli (Cosman & Vecera, 2009, 2010a), yet a follow-up study qualified that evidence by showing the frequency of the abrupt onset could alter distractor processing under high perceptual load (Cosman & Vecera, 2010b). Both sets of results changed due to a specific influence that could interact with top-down expectations about the task.…”

Context-dependent control over attentional capture.

“…With respect to the current results, it is possible that increased inter-item competition in heterogeneous displays may engender stronger top-down control, ultimately leading to less distraction by salient, task-irrelevant information. This view is supported by a number of recent studies demonstrating reduced attentional capture in heterogeneous relative to homogeneous search arrays (e.g., Lamy & Tsal, 1999; Cosman & Vecera, 2009; 2010a; 2010b), as well as studies showing that other manipulations that influence local competition modulate the likelihood of distraction (Torralbo & Beck, 2008; Proulx & Egeth, 2006; Roper, Cosman, & Vecera, submitted). However, we don’t wish to argue that either explicit, strategic factors or differences in the scale of attention play no role in influencing attentional capture, but rather that that the attentional control system likely relies on multiple bottom-up and top-down factors that interact to determine capture in a given situation (see Cosman & Vecera, 2010a).…”

Directing driver attention with augmented reality cues

“…Other findings, however, indicate that such attentional capture only occurs for items that are task relevant; attentional capture is contingent on observer goals (Folk, Remington, & Johnston, 1992). Further, attentional capture is reduced under dual-task situations (Boot, Brockmole, & Simons, 2005) and in visually complex displays (Cosman & Vecera, 2009, 2010), two results that suggest that in-car alerts might do little to summon drivers’ attention because driving involves multitasking and searching complex visual scenes.…”