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)     

Mechanisms of attentional priority.

When a single abrupt onset occurs in a multielement visual display, it captures attention, possibly by generating an attentional interrupt that designates onsets as being of high priority. In 3 experiments, the mechanisms subserving attentional priority setting were investigated. A total of 56 Ss searched for a prespecified target letter among multiple distractor letters, half of which had abrupt onsets and half of which did not. The target, when present, was equally often an onset element and a no-onset element. Several models for attentional priority, differing in how many onset elements have priority over no-onset elements, were assessed. The data support a model in which approximately 4 onset stimuli are processed before any no-onset stimuli are processed. Two attentional priority mechanisms are proposed: (1) queuing of a limited number of high-priority elements and (2) temporally modulated decay of attentional priority tags. (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)     

A static color discontinuity can capture spatial attention when the target is an abrupt-onset singleton.

C. L. Folk, R. W. Remington, and J. C. Johnston's (1992) contingent involuntary orienting hypothesis states that a salient visual feature will involuntarily capture attention only when the observer's attentional set includes similar features. In four experiments, when the target's relevant feature was its being an abruptly onset singleton, attentional capture occurred for a static discontinuity cue that was the boundary between a group of red Xs contiguously joined to a group of green Os within a single row. Such an attentional capture effect is novel and contrary to Folk et al.'s (1992) hypothesis, because the attentional set for the target should have included abrupt onset but not color discontinuity, which was the feature that captured attention. These capture effects were involuntary because they occurred even when the target never appeared in the same location as the cue, and color could not have been used as a cue to signal the appearance of the target array (cf. B. S. Gibson & E. M. Kelsey, 1998). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

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)     

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)     

Visual quality and attentional capture: A challenge to the special role of abrupt onsets.

This article investigates the nature of stimulus-driven attentional capture. Previous studies (e.g., J. Jonides & S. Yantis, see record 1989-03735-001) have suggested that only a single visual feature—abrupt visual onset—can elicit stimulus-driven attentional capture. Two experiments are reported that challenge the special status of abrupt onsets in attentional capture. In particular, this evidence suggests that abrupt onsets appear to attenuate display-size effects only in certain experimental contexts that inadvertently increase the ease with which they are perceived. Consequently, the special status attributed to abrupt onsets is argued to derive from their higher visual quality. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

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)     

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)     

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)     

Attentional capture in singleton-detection and feature-search modes.

Six experiments were conducted to determine the circumstances under which an irrelevant singleton captures attention. Subjects searched for a target while ignoring a salient distractor that appeared at different stimulus onset asynchronies (SOAs) prior to each search display. Spatial congruency and interference effects were measured. The strategies available to find the target were controlled (only singleton-detection mode, only feature-search mode, or both search strategies available). An irrelevant abrupt onset captured attention in search for a color target, across SOAs, whatever strategies were available. In contrast, in search for a shape target, an irrelevant color singleton captured attention in the singleton-detection condition but delayed response at its location in the feature-search condition, across SOAs. When both strategies were available, capture was short lived (50- to 100-msec SOAs). The theoretical implications of these findings in relation to current views on attentional capture are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of object onset on the distribution of visual attention.

There now exists considerable evidence to suggest that the appearance of a new object in the visual field captures visual attention. One of the consequences of this attentional capture is that the object initiates a redistribution of attentional resources across visual space. This is classically observed in the precuing paradigm in which the onset of an abrupt cue influences the processing of a subsequently presented target. The present research describes a new phenomenon that occurs as a result of a new object appearing in the visual field. A stimulus presented in a region of space adjacent to a comer of an onsetting object receives an enhancement of processing relative to a stimulus presented adjacent to one of the object's straight edges. With the use of 2 converging methods, evidence is presented that suggests that the effect is a higher order attentional phenomenon whereby greater resources become directed to the comers of objects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Influence of attentional capture on oculomotor control.

Previous research has shown that when searching for a color singleton, top-down control cannot prevent attentional capture by an abrupt visual onset. The present research addressed whether a task-irrelevant abrupt onset would affect eye movement behavior when searching for a color singleton. Results show that in many instances the eye moved in the direction of the task-irrelevant abrupt onset. There was evidence that top-down control could neither entirely prevent attentional capture by visual onsets nor prevent the eye from starting to move in the direction of the onset. Results suggest parallel programming of 2 saccades: 1 voluntary goal-directed eye movement toward the color singleton target and 1 stimulus-driven eye movement reflexively elicited by the abrupt onset. A neurophysiologically plausible model that can account for the current findings is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attentional orienting within visual field in a lexical decision task.

The influence of spatial attention on lexical decisions to lateralized target letter-strings appearing either along with a distractor (Experiment 1) or in an otherwise empty field (Experiments 2–6) was examined. Attentional orienting was controlled by peripheral (Experiments 1, 2, 3, and 6) and central (Experiments 4–5) cuing methods. Manipulations of spatial attention, including cue validity and cue–target stimulus onset asynchrony, were combined with manipulations of word frequency in Experiments 3-6. All the attentional manipulations were effective, but they did not modify the right visual field advantage in word performance, In addition, the attentional effects did not interact with either the presence or absence of distractors or with stimulus familiarity. Implications of these results regarding the influence of spatial attention (the posterior attention system) on word processing are discussed. (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)     

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)     

Interactive Activation in Visual Word Recognition: Constraints Imposed by the Joint Effects of Spatial Attention and Semantics.

Two lexical-decision experiments investigated the effects of semantic priming and stimulus intensity when target location varied and was cued by an abrupt onset. In Experiment 1, the spatial cue was a good predictor of target location, and in Experiment 2 it was not. The results indicate that word recognition processes were postponed until spatial attention was focused on the target and that whether attention further affected word recognition depended on cue validity. The joint effects of cue validity and priming interacted when cue validity was high but were additive when cue validity was low. The joint effects of stimulus intensity and semantic priming also varied according to cue validity (i.e., interactive when high and additive when low). The results are discussed in terms of their implications for visual word recognition, the distinction between exogenous and endogenous spatial attention, and how attention is affected by visual word recognition processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The masking account of attentional capture: A reply to Yantis and Jonides (1996).

B. S. Gibson (see record 1997-06229-001) has recently argued that stimulus-driven attentional capture by abrupt onsets (or new objects) may be due to forward masking of the no onsets (or old objects) by preceding figure-eight placeholders. Three experiments are reported in the present article that address recent arguments and evidence offered by S. Yantis and J. Jonides (see record 1997-06254-001) against the masking account of attentional capture. Contrary to Yantis and Jonides's claims, the present study provides strong support for the masking account of attentional capture. Thus, the masking account appears to provide the best explanation of the existing data. (PsycINFO Database Record (c) 2010 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)     

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)