Stimulus-driven attentional capture by a static discontinuity between perceptual groups.

After C. L. Folk, R. W. Remington, and J. C. Johnston (1992) proposed their contingent-orienting hypothesis, there has been an ongoing debate over whether purely stimulus-driven attentional capture can occur for visual events that are salient by virtue of a distinctive static property (as opposed to a dynamic property such as abrupt onset). The present study identified 3 methodological criteria for establishing that attentional capture is stimulus driven and not contingent on top-down attentional control settings. In 5 experiments, attentional capture occurred for a static discontinuity at the boundary between one group of homogeneous items (red Xs) abutted next to a group of homogeneous items that were featurally different (green Xs) within a single row. Experiment 1 intentionally violated one of the criteria for demonstrating stimulus-driven capture so as to establish that contingent attentional capture can occur for this novel type of static cue. In the remaining 4 experiments, even with all 3 criteria for stimulus-driven capture partially or completely satisfied, the static discontinuity captured attention. These attentional capture effects are the first to be obtained when all 3 criteria for establishing that they are purely stimulus driven have been satisfied. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The Time Course of the Contingent Spatial Blink.

Attentional capture is the unintentional deployment of attention to a task-irrelevant but attentionally salient object. The contingent involuntary orienting hypothesis states that it occurs only if a distractor's property matches current top-down attentional control settings (Folk, Remington, & Johnston, 1992). Folk, Leber, and Egeth (2002) found that monitoring a central RSVP stream for a coloured target led to spatial attentional capture by a peripheral distractor that matched the target colour. Using a similar paradigm, we explored the time course of this spatial blink. Implications of this study for current accounts of the attentional capture phenomenon are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Stimulus-driven attentional capture and attentional control settings.

J. Jonides and S. Yantis (1988) found that abrupt-onset singletons capture attention in visual search when onset is orthogonal to the target's defining and reported attributes and that color and brightness singletons do not. They concluded that abrupt onset may be unique in capturing visual attention. C. L. Folk et al (1992) challenge this conclusion and argue that (1) the occurrence of attentional capture is contingent on the adoption of an appropriate attentional control setting by the observer and (2) properties other than onset (in particular, color) can capture attention involuntarily. In this article, each of these claims is critically evaluated, and it is argued that the results by Folk et al, though important, do not definitively corroborate either one. The available evidence concerning stimulus-driven attentional capture is summarized, and 3 empirical generalizations that characterize the evidence are advanced. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Contingent attentional capture: A reply to Yantis (1993).

The authors (1992) recently proposed that involuntary shifts of spatial attention, even those elicited by abrupt visual onsets, are contingent on variable internal control settings. S. Yantis (1993) argues that the results of J. Jonides and Yantis (1988) significantly challenge this hypothesis and that the paradigm of C. L. Folk et al (1992) is inappropriate for investigating stimulus-driven attentional capture. Yantis's concerns are addressed, and it is concluded that the contingent involuntary orienting hypothesis in fact provides a unified and parsimonious account of the data on attentional capture. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attentional capture with rapidly changing attentional control settings.

The classic theory of spatial attention hypothesized 2 modes, voluntary and involuntary. Folk, Remington, and Johnston (1992) reported that even involuntary attention capture by stimuli requires a match between stimulus properties and what the observer is looking for. This surprising conclusion has been confirmed by many subsequent studies. In these studies, however, the observer typically looks for the same property throughout an entire session. Real-world behavior, in contrast, often requires frequent shifts in attentional set. The present study examined whether such shifts weaken attentional settings, allowing task-irrelevant objects to capture attention. Surprisingly, fluctuating control settings did not increase vulnerability to capture by salient stimuli (color singletons and abrupt onsets). We conclude that the attention control system is remarkably flexible, able to rapidly and fully adopt new settings and abandon old settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of relational information in contingent capture.

On the contingent capture account, top-down attentional control settings restrict involuntary attentional capture to items that match the features of the search target. Attention capture is involuntary, but contingent on goals and intentions. The observation that only target-similar items can capture attention has usually been taken to show that the content of the attentional control settings consists of specific feature values. In contrast, the present study demonstrates that the top-down target template can include information about the relationship between the target and nontarget features (e.g., redder, darker, larger). Several spatial cuing experiments show that a singleton cue that is less similar to the target but that shares the same relational property that distinguishes targets from nontargets can capture attention to the same extent as cues that are similar to the target. Moreover, less similar cues can even capture attention more than cues that are identical to the target when they are relationally better than identical cues. The implications for current theories of attentional capture and attentional guidance are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Stimulus-driven capture and attentional set: Selective search for color and visual abrupt onsets.

Recent evidence (C. L. Folk et al; see record 1993-12300-001) suggests that attentional capture is contingent on the attentional control setting induced by the task demands. Because the experiments on which these conclusions are based can be criticized for several reasons, the contingent capture hypothesis was tested using 2 visual search tasks in which Ss searched multielement displays in which a color singleton and onset singleton were simultaneously present. Both experiments show that the contingent capture hypothesis does not hold: Irrespective of attentional set, attention was captured by the most salient singleton. The findings suggest a stimulus-driven model of performance in which selection is basically determined by the properties of the featural singletons present in the visual field. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Contingent capture for onsets and offsets: Attentional set for perceptual transients.

Four experiments were conducted to examine whether attentional set affects the ability of visual transients (onsets and offsets) to capture attention. In the experiments, visual search for an identity-defined target was conducted. In the first 3 experiments, the target display either onset entirely or was revealed by offsetting camouflaging line segments to reveal letters. Prior to the target display, there was a noninformative cue, either an onset or an offset, at one of the potential target locations. Cues that shared the same transient feature as the target display captured attention. The lack of predictable target transients led to attentional capture by all forms of transients. The final experiments with luminance changes without offsets or onsets showed attentional capture when the luminance changes were large. The results suggest that attentional set can be broadly or narrowly tuned to detect changes in luminance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Involuntary covert orienting is contingent on attentional control settings.

Four experiments tested a new hypothesis that involuntary attention shifts are contingent on the relationship between the properties of the eliciting event and the properties required for task performance. In a variant of the spatial cuing paradigm, the relationship between cue property and the property useful in locating the target was systematically manipulated. In Exp 1, invalid abrupt-onset precues produced costs for targets characterized by an abrupt onset but not for targets characterized by a discontinuity in color. In Exp 2, invalid color precues produced greater costs for color targets than for abrupt-onset targets. Exp 3 provided converging evidence for this pattern. Exp 4 investigated the boundary conditions and time course for attention shifts elicited by color discontinuities. The results of these experiments suggest that attention capture is contingent on attentional control settings induced by task demands. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Abrupt visual onsets and selective attention: Voluntary versus automatic allocation.

The hypothesis that abrupt visual onsets capture attention automatically, as suggested by S. Yantis and J. Jonides (see record 1985-19225-001), was tested in four experiments. A centrally located cue directed attention to one of several stimulus positions in preparation for the identification of a target letter embedded in an array of distractor letters. In all experiments, one stimulus (either the target or one of the distractors) had an abrupt onset; the remaining letters did not. The effectiveness of the cue was manipulated (varying either its duration or its predictive validity) to test whether abrupt onsets capture attention even when subjects are in a highly focused attentional state. Results showed that onsets do not necessarily capture attention in violation of an observer's intentions. A mechanism for partially automatic attentional capture by abrupt onset is proposed, and the diagnosticity of the intentionality criterion for automaticity is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The structure of attentional control: Contingent attentional capture by apparent motion, abrupt onset, and color.

Five spatial cuing experiments tested 2 hypotheses regarding attentional capture: (1) Attentional capture is contingent on endogenous attentional control settings, and (2) attentional control settings are limited to the distinction between dynamic and static discontinuities as proposed by C. L. Folk et al (see record 1993-12300-001). In Exps 1 and 2, apparent-motion precues produced significant costs in performance for targets signaled by motion but not for targets signaled by color or abrupt onset. Exp 3 established that this pattern is not due to differences in the difficulty of target discrimination. Exps 4 and 5 revealed asymmetric capture effects between abrupt onset and apparent motion related to stimulus salience. Results support the hypotheses of Folk et al and suggest that stimulus salience may also play a role in attentional capture. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

When something old becomes something new: Spatiotemporal object continuity and attentional capture.

This article examines the possibility that the visual system treats dynamic cues as instances of new perceptual objects under some circumstances. Using the contingent capture paradigm (C. L. Folk, R. W. Remington, & J. C. Johnston, 1992), the author compared luminance change cues of different magnitude for their ability to capture attention when participants were set for new objects. Whereas small luminance changes failed to produce attentional capture, large luminance changes indeed captured attention, suggesting that they were treated as compatible with the participants' attentional set for new objects. It is argued that sufficiently large luminance transients led to a disruption of spatiotemporal object continuity and precipitated the emergence of a new perceptual object. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Characteristics of covert and overt visual orienting: Evidence from attentional and oculomotor capture.

Five visual search experiments found oculomotor and attentional capture consistent with predictions of contingent orienting, contrary to claims that oculomotor capture is purely stimulus driven. Separate saccade and attend-only conditions contained a color target appearing either singly, with an onset or color distractor, or both. In singleton mode, onsets produced oculomotor and attentional capture. In feature mode, capture was absent or greatly reduced, providing evidence for top-down modulation of both types of capture. Although attentional capture by color abstractors was present throughout, oculomotor capture by color occurred only when accompanied by transient change, providing evidence for a dissociation between oculomotor and attentional capture. Oculomotor and attentional capture appear to be mediated by top-down attentional control settings, but transient change may be necessary for oculomotor capture. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of Task Relevance and Stimulus-Driven Salience in Feature-Search Mode.

Attentional allocation in feature-search mode (W. F. Bacon & H. E. Egeth, 1994) is thought to be solely determined by top-down factors, with no role for stimulus-driven salience. The authors reassessed this conclusion using variants of the spatial cuing and rapid serial visual presentation paradigms developed by C. L. Folk and colleagues (C. L. Folk, R. W. Remington, & J. C. Johnston, 1992; C. L. Folk, A. B. Leber, & H. E. Egeth, 2002). They found that (a) a nonsingleton distractor that possesses the target feature produces attentional capture, (b) such capture is modulated by bottom-up salience, and (c) resistance to capture by irrelevant singletons is mediated by inhibitory processes. These results extend the role of top-down factors in search for a nonsingleton target while arguing against the notion that effects of bottom-up salience and top-down factors on attentional priority are strictly encapsulated within distinct search modes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Top-down contingencies in peripheral cuing: The roles of color and location.

According to contingent-processing accounts, peripheral cuing effects are due to the cues' inadvertent selection for processing by control settings set up for targets (e.g., C. L. Folk, R. W. Remington, & J. C. Johnston, 1992). Consequently, cues similar to targets should have stronger effects than do dissimilar cues. In the current study, this prediction is confirmed for cue-target combinations similar or dissimilar in the static features of color (Experiments 1-3) and location (Experiment 4), even when both cues and targets share the dynamic feature of abrupt onset. Perceptual priming (Experiment 2) and reallocation of attention did not account for similar-dissimilar differences (Experiments 3 and 4). The results are best explained by top-down-contingent attentional effects of the similar cues. Implications for bottom-up accounts of peripheral cuing effects are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aging and involuntary attention capture: Electrophysiological evidence for preserved attentional control with advanced age.

The present study examined whether people become more susceptible to capture by salient objects as they age. Participants searched a target display for a letter in a specific color and indicated its identity. In Experiment 1, this target display was preceded by a non-informative cue display containing one target-color box, one ignored-color box, and two white boxes. On half of the trials, this cue display also contained a salient-but-irrelevant abrupt onset. To assess capture by the target-color cue, we used the N2pc component of the event-related potential, thought to reflect attentional allocation to the left or right visual field. The target-color box in the cue display produced a substantial N2pc effect for younger adults and, most importantly, this effect was not diminished by the presence of an abrupt onset. Therefore, the abrupt onset was unable to capture attention away from the target-color cue. Critically, older adults demonstrated the same resistance to capture by the abrupt onset. Experiment 2 extended these findings to irrelevant color singleton cues. Thus, we argue that the ability to attend to relevant stimuli and resist capture by salient-but-irrelevant stimuli is preserved with advancing age. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Attentional capture by working memory contents.

There has been controversy on whether working memory (WM) contents automatically guide attention. The present study tried to replicate the effect of WM-based attentional capture using an adaption of Downing's (2000) paradigm, in which WM and attentional capture were combined. Subjects were presented with an attention display containing two objects, one of which could be precued by a matching item being held in WM. As measured by a probe discrimination task, the memory-matching object had a privileged status to capture attention regardless of the stimulus onset asynchronies between the memory cue and the attention display, even when there was absolutely no benefit for subjects to bias attention in favour of the memory match. These results suggest that WM contents guide attention in an involuntary manner. The implications of current findings for understanding of WM effects on visual selection are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Contingent attentional capture by top-down control settings: Converging evidence from event-related potentials.

Theories of attentional control are divided over whether the capture of spatial attention depends primarily on stimulus salience or is contingent on attentional control settings induced by task demands. The authors addressed this issue using the N2-posterior- contralateral (N2pc) effect, a component of the event-related brain potential thought to reflect attentional allocation. They presented a cue display followed by a target display of 4 letters. Each display contained a green item and a red item. Some participants responded to the red letter and others to the green letter. Converging lines of evidence indicated that attention was captured by the cues with the same color as the target. First, these target-color cues produced a cuing validity effect on behavioral measures. Second, distractors appearing in the cued location produced larger compatibility effects. Third, the target-color cue produced a robust N2pc effect, similar in magnitude to the N2pc effect to the target itself. Furthermore, the target-color cue elicited a similar N2pc effect regardless of whether it competed with a simultaneous abrupt onset. The findings provide converging evidence for attentional capture contingent on top-down control settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Stimulus-driven attentional capture is contingent on attentional set for displaywide visual features

This research showed that the current criterion for stimulus-driven attentional capture is not sufficient to rule out goal-directed processes that are critical for producing attentional capture. This was shown by demonstrating a contingency between displaywide visual features (i.e., features that signal the appearance of the task-relevant target display as a whole) and the features that capture attention. In Experiment 1, the target display was signaled by both color and onset; in Experiment 2, the target display was signaled only by onset. As expected, Experiment 1 showed that task-irrelevant color and onset distractors both captured attention, whereas Experiment 2 showed that only onset distractors captured attention. These contingencies suggest that the strongest evidence currently available for stimulus-driven attentional capture may be caused by goal-directed processes.     

Categorically defined targets trigger spatiotemporal visual attention.

Transient attention to a visually salient cue enhances processing of a subsequent target in the same spatial location between 50 to 150 ms after cue onset (K. Nakayama & M. Mackeben, 1989). Do stimuli from a categorically defined target set, such as letters or digits, also generate transient attention? Participants reported digit targets among keyboard symbols in a changing array of 8 items. When 1 target preceded a second target in the same location at a stimulus onset asynchrony of 107 ms (but not 213 ms), the second target was reported more often than in a condition in which there was no leading target. When the 2 targets were at different locations, report of the second target was impaired. With both letters and digits as targets, the enhancement effect was shown not to be due to category priming. Critically, the attentional benefit was present whether or not participants reported the leading target. Transient attention, contingent attentional capture, popout, and Lag 1 sparing in the attentional blink may involve a common mechanism for orienting processing resources towards salient and task relevant stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)