Temporal attentional capture: Effects of irrelevant singletons on rapid serial visual search

Abstract

In order to behave effectively in a complicated world, people must be able to focus their attention on goalrelevant stimuli at the expense of irrelevant ones. However, it is also important that attention can be captured by irrelevant stimuli when they are unique and may, therefore, signal potentially important changes in the environment. A central line of attention research has investigated attentional capture by such unique yet task-irrelevant singleton stimuli.It has long been established that attentional allocation toward stimuli in nontarget locations produces performance costs, as has been shown in spatial-cuing studies (e.g., Jonides, 1980;Posner, Nissen, & Ogden, 1978), as well as in studies of attentional capture by a singleton item presented within a visual search display (e.g., Jonides & Yantis, 1988;Theeuwes, 1992). Both these areas of research address the consequences of paying attention to irrelevant spatial locations. More recently, research has begun to address the effects of attentional allocation to irrelevant temporal positions. However, very little previous research has investigated the possibility of attentional capture by stimuli appearing at irrelevant temporal positions. Here, we ask whether a unique yet irrelevant singleton can produce temporal attentional capture during a rapid serial visual presentation (RSVP) search task.A few recent studies have provided some evidence that attentional allocation to items presented at irrelevant temporal positions can lead to performance costs. For example, Folk, Leber, and Egeth (2002) have shown attentional capture in an RSVP task by color singleton distractors flanking the central RSVP letters. However, since the singleton distractors in this study were spatially separated from the targets, it is not clear whether the capture effects were due to diversion of attention to an irrelevant spatial location (i.e., spatial attentional capture) or to an irrelevant temporal position (i.e., temporal attentional capture), or both.Research into the attentional blink (AB) has shown that attending to (rather than ignoring) the first of two targets can prevent participants from detecting the second, as long as the second target occurs within 500 msec of the first (e.g., Broadbent & Broadbent, 1987;Raymond, Shapiro, & Arnell, 1992). Thus, attentional allocation toward one item in a serial stream can interfere with processing of an item at a different point in the stream. These results cannot be explained in terms of spatial attention, because all the items were presented in a central RSVP stream. However, since participants respond primarily to the first target and only later to the second target, the AB is likely to involve both response-and memory-related effects (e.g., Jolicoeur, 1998). Moreover, most of the AB research assesses the consequences of attending deliberately to target stimuli and, as such, does not provide information about the involuntary capture of attention.Recent findings from the AB paradigm that an ignored first target or additional singleton ...

Attentional capture in serial audiovisual search tasks

“…We note that the effects of singletons appearing after the target are likely to have been underestimated in the present design, since the participants were able to respond as soon as the target had been presented (making it possible that they could have responded or initiated a response before presentation of a following singleton). Nevertheless, these findings are reminiscent of the pattern of results found in previous studies of visual attentional capture in sequential search tasks (e.g., Dalton & Lavie, 2006;Folk et al, 2002), in which attentional capture effects have typically been found only for singleton items preceding the target in the stream, and not for singletons that follow the target. These findings also appear to resemble the AB effect, in which attentional allocation toward a particular item in an RSVP stream impedes the processing of subsequent items.…”

“…The results may, therefore, reflect deliberate attentional allocation toward these singletons because they possess a task-relevant feature.By contrast, Dalton and Lavie (2006) …”

Attentional capture decreases when distractors remain visible during rapid serial visual presentations

“…Although the observers were set to find a color singleton, we believe it is highly likely that the salient items in the temporal domain were able to capture attention. Indeed, when the observers adopted the singleton detection mode, salient items within a different stimulus feature could capture attention in the temporal domain (interdimensional capture; Dalton & Lavie, 2006;Inukai, Kawahara, & Kumada, 2010). Since the peripheral items could not serve as targets, the system disengaged the focus from the location of the singleton distractor and started to reengage with the center.…”

Nonspatial interdimensional attentional capture

“…However, one addressed within-dimensional capture (Folk, Leber, & Egeth, 2008). Although the other (Dalton & Lavie, 2006) focused on cross-dimensional capture, it did not compare the effect of search mode. Therefore, we need to investigate the bottom right quadrant of Table 1 to fully understand the effect of top-down knowledge on attentional capture.…”

“…However, it is unclear whether the same is true when the singleton distractor belongs to a different stimulus dimension. Second, in terms of cross-dimensional capture, Dalton and Lavie (2006) demonstrated that nonspatial attention was captured by singleton distractors. Their observers searched for a size oddball among a stream of medium-sized nontarget letters and reported whether the target size was small or large.…”