Top-down Attentional Control Settings Research Articles

The role of the left dorsolateral prefrontal cortex in attentional bias

The DLPFC is thought to be critically involved in maintaining attention away from behaviourally irrelevant information, and in the establishment of attentional control settings. These play an important role in the phenomenon of top-down bias to features in the visual field – also known as attentional bias. This paper probes the involvement of the left DLPFC in attentional bias by manipulating its cortical excitability via tDCS and then analysing these effects following an induced attentional bias towards the colour green. Although both anodal and cathodal tDCS over the left DLPFC decrease distractibility caused by biased but irrelevant objects, further interrogation of our data reveals theoretically differential mechanisms for each type of stimulation. Anodal tDCS appears to increase cognitive control over attentional bias-related items that are behaviourally irrelevant, allowing for their efficient disregard. In contrast, cathodal tDCS appears to lessen the overall effect of the induced attentional bias, potentially by reducing the influence of top-down modulated attentional control settings thus preventing the implementation of the control setting favouring green items. These results suggest a potential causal role of the left DLPFC in the cognitive mechanism underlying attentional bias.

Testing the top-down contingent capture of attention for abrupt-onset cues: Evidence from cue-elicited N2pc.

Many studies using N2pc as a marker of attentional capture have demonstrated top-down contingent capture for salient color singletons: Among all salient cues that are not predictive of the target location, only cues similar to searched-for target features, and thus, matching to the top-down attentional control settings capture attention. This is reflected in matching cue's elicitation of an N2pc and a cueing effect in behavior, and the absence of the corresponding effects for non-matching cues (with features dissimilar to that of the searched-for targets). Yet, with abrupt-onset cues, corresponding evidence is missing, inviting speculations about the potential of abrupt-onset cues to capture attention followed by quick suppression within the target displays. Here, we used two types of abrupt-onset cues to test if capture by such cues also adheres to the contingent-capture principle: matching abrupt-onset cues with a color similar to the top-down control settings and non-matching abrupt-onset cues with a color different from all searched-for targets. With the help of these cues, top-down contingent capture was supported. Only matching abrupt-onset cues elicited an N2pc and a behavioral cueing effect. Depending on the exact side conditions, non-matching cues either elicited no N2pc or a PD (i.e., evidence of active suppression). Results are discussed against the background of competing theories on attention capture by abrupt-onset cues.

Task-irrelevant optic flow guides attention in visual search.

Motion is an important factor in visual information processing. Studies have shown that global optic flow guides attention, but it remains unclear whether this attentional guidance occurs regardless of top-down attentional control settings for another endogenous cue. To address this issue, we developed a visual search paradigm in which a task-irrelevant optic flow starts and stops prior to a visual search task itself. Participants first observed an initial optic flow motion pattern for a brief period; next, they searched a static display for a target amongst multiple distractors. Results showed faster target detection when a target's locus coincided with the implied focus of expansion (FOE) from the preceding optic flow (vs. other loci). Eye-movement analyses revealed that initial saccades were drawn to the FOE during optic flow exposures and that relatively few saccades were needed to find targets contingent to the preceding FOE. The advantage of FOE for finding target occurred even when a salient feature singleton captured attention or when a task-relevant feature singleton was prioritized. Results of six experiments suggest that attentional control settings for a feature singleton do not over-ride a sustained influence of optic flow on attentional guidance.

The different roles of category- and feature-specific attentional control settings on attentional enhancement and inhibition.

Contingent attentional capture suggests that top-down attentional control settings (ACS) can enhance attentional processing of task-relevant properties and inhibit attentional processing of task-irrelevant properties. However, it remains unclear how ACS operates when a distractor has both task-relevant and task-irrelevant characteristics. In the present study, two lateralized ERP components, N2pc and distractor positivity (Pd), were employed as markers of attentional enhancement and inhibition, respectively. The degree of matching between a distractor and a conjunctively defined target was manipulated to illustrate attentional guidance by category-specific ACS (cACS) and feature-specific ACS (fACS), and the relative position between the distractor and the target was manipulated to isolate the processing of the distractor and the target. Experiment 1 showed that, with a long display duration for searching, a reliable N2pc component was elicited by a distractor that was feature-matched but category-mismatched (C-F+) relative to the target-defined properties, suggesting an enhancing effect of fACS. In contrast, Experiment 2 demonstrated that, with a short display duration, a Pd component was elicited by a distractor that was feature-mismatched but category-matched (C+F-) relative to the target-defined properties, suggesting an inhibitory effect of fACS. Moreover, both attentional enhancement and inhibition were only triggered by fACS but not by cACS. In summary, ACS can enhance target-relevant properties or inhibit target-irrelevant properties in response to the display duration, and fACS affects both enhancement and inhibition more than cACS.

Object-based selection is contingent on attentional control settings.

The visual system allocates attention in object-based and location-based modes. However, the question of when attention selects objects and when it selects locations remains poorly understood. In this article, we present variations on two classic paradigms from the object-based attention literature, in which object-based effects are observed only when the object feature matches the task goal of the observer. In Experiment 1, covert orienting was influenced by task-irrelevant rectangles, but only when the target color matched the rectangle color. In Experiment 2, the region of attentional focus was adjusted to the size of task-irrelevant objects, but only when the target color matched the object color. In Experiment 3, we ruled out the possibility that contingent object-based selection is caused by color-based intratrial priming. These demonstrations of contingent object-based attention suggest that object-based selection is neither mandatory nor default, and that object-based effects are contingent on simple, top-down attentional control settings.

Age-related emotional bias in processing two emotionally valenced tasks.

Previous studies suggest that older adults process positive emotions more efficiently than negative emotions, whereas younger adults show the reverse effect. We examined whether this age-related difference in emotional bias still occurs when attention is engaged in two emotional tasks. We used a psychological refractory period paradigm and varied the emotional valence of Task 1 and Task 2. In both experiments, Task 1 was emotional face discrimination (happy vs. angry faces) and Task 2 was sound discrimination (laugh, punch, vs. cork pop in Experiment 1 and laugh vs. scream in Experiment 2). The backward emotional correspondence effect for positively and negatively valenced Task 2 on Task 1 was measured. In both experiments, younger adults showed a backward correspondence effect from a negatively valenced Task 2, suggesting parallel processing of negatively valenced stimuli. Older adults showed similar negativity bias in Experiment 2 with a more salient negative sound ("scream" relative to "punch"). These results are consistent with an arousal-bias competition model [Mather and Sutherland (Perspectives in Psychological Sciences 6:114-133, 2011)], suggesting that emotional arousal modulates top-down attentional control settings (emotional regulation) with age.

Stimulus-driven attentional capture by subliminal onset cues

In two experiments, we tested whether subliminal abrupt onset cues capture attention in a stimulus-driven way. An onset cue was presented 16 ms prior to the stimulus display that consisted of clearly visible color targets. The onset cue was presented either at the same side as the target (the valid cue condition) or on the opposite side of the target (the invalid cue condition). Because the onset cue was presented 16 ms before other placeholders were presented, the cue was subliminal to the participant. To ensure that this subliminal cue captured attention in a stimulus-driven way, the cue's features did not match the top-down attentional control settings of the participants: (1) The color of the cue was always different than the color of the non-singleton targets ensuring that a top-down set for a specific color or for a singleton would not match the cue, and (2) colored targets and distractors had the same objective luminance (measured by the colorimeter) and subjective lightness (measured by flicker photometry), preventing a match between the top-down set for target and cue contrast. Even though a match between the cues and top-down settings was prevented, in both experiments, the cues captured attention, with faster response times in valid than invalid cue conditions (Experiments 1 and 2) and faster response times in valid than the neutral conditions (Experiment 2). The results support the conclusion that subliminal cues capture attention in a stimulus-driven way.

Semantic Priming Produces Contingent Attentional Capture by Conceptual Content

There is substantial evidence that the capture of spatial attention by salient, irrelevant stimuli is subject to modulation by top-down task set. To accommodate such findings, the theory of Contingent Attention Capture (CAC) proposes that the attention allocation system is "configurable" such that a given stimulus will only capture attention if it is consistent with current top-down "attentional control settings" related to behavioral goals. Most of the previous research on CAC has focused on capture by salient, low level properties, implying that attentional control settings are limited to working memory templates for simple features such as color, orientation, motion, singleton-ness, etc. A recent study, however, found that relatively high-level, categorical content of an image can capture attention if the task requires monitoring for exemplars from that category (Wyble, Folk, & Potter, 2013). This suggests that the activation of categorical representations in semantic memory can also serve as top-down attentional control settings. The present study tested whether these effects are truly the result of semantic memory activation by testing whether images that are semantically related to the task-relevant category also capture attention. Subjects monitored a central RSVP stream for any exemplar (e.g., a ferris wheel) from a pre-specified semantic category (e.g., amusement park rides). Two frames prior to the target image, irrelevant distractor images appeared above and below the stream, one of which could be another exemplar from the relevant category (e.g., bumper cars), an image of a related item (e.g., cotton candy), or an image of an unrelated item (e.g., a hammer). Distractors consisting of exemplar and semantically related images both produced a decrement in target report relative to semantically unrelated distractors, suggesting that the attention allocation system can be configured not only through templates in working memory, but also through the activation and priming of long-term semantic memory representations. Meeting abstract presented at VSS 2014

Using response time distributions to examine top-down influences on attentional capture

Three experiments examined contingent attentional capture, which is the finding that cuing effects are larger when cues are perceptually similar to a target than when they are dissimilar to the target. This study also analyzed response times (RTs) in terms of the underlying distributions for valid cues and invalid cues. Specifically, an ex-Gaussian analysis and a vincentile analysis examined the influence of top-down attentional control settings on the shift and skew of RT distributions and how the shift and the skew contributed to the cuing effects in the mean RTs. The results showed that cue/target similarity influenced the size of cuing effects. The RT distribution analyses showed that the cuing effects reflected only a shifting effect, not a skewing effect, in the RT distribution between valid cues and invalid cues. That is, top-down attentional control moderated the cuing effects in the mean RTs through distribution shifting, not distribution skewing. The results support the contingent orienting hypothesis (Folk, Remington, & Johnston, Journal of Experimental Psychology: Human Perception and Performance, 18, 1030-1044, 1992) over the attentional disengagement account (Theeuwes, Atchley, & Kramer, 2000) as an explanation for when top-down attentional settings influence the selection of salient stimuli.

Priming of Control: Implicit Contextual Cuing of Top-down Attentional Set

Cognitive models have long distinguished between "automatic" associative processes that can be triggered in a bottom-up fashion, and "controlled" processes, where internal goals guide information processing in a deliberate, top-down manner. However, recent behavioral studies have cast doubt on the validity of this dichotomy, showing that implicit contextual cues can modulate performance in a way suggestive of an associative triggering of specific top-down control states. Here, we harnessed functional magnetic resonance imaging in humans to test whether these behavioral findings truly reflect online, bottom-up priming of top-down attentional control settings. Using a flanker interference task where stimulus location cued the likelihood of incongruent trials, we found that the behavioral phenomenon of implicit, context-specific improvements in interference resolution was mirrored in hemodynamic activity in the medial superior parietal lobule (mSPL), previously implicated in voluntary (as opposed to primed) attention shifts. Moreover, the mSPL displayed context-specific functional coupling with visual regions involved in processing the flanker stimuli, and the modulation of the latter was predictive of the behavioral effects. Finally, the implementation of this contextual control was "on the fly," that is, it was primed online by a switch to the context associated with high conflict. These results suggest that top-down control states can be bound into episodic event representations and can subsequently be primed by other features of those representations. Together, our findings illustrate a more intimate link between associative and controlled processing than is traditionally assumed, and place the neural substrate of that linkage in the posterior parietal cortex.

Distractibility and top-down attentional control in children using a cochlear implant

Event Abstract Back to Event Distractibility and top-down attentional control in children using a cochlear implant Marc R. Kamke1*, Jeanette Van Luyn2 and Jill Harris1, 3 1 The University of Queensland, The Queensland Brain Institute, Australia 2 The University of Queensland, School of Psychology, Australia 3 The University of Queensland, Minerals Industry Safety and Health Centre, Sustainable Minerals Institute, Australia Early auditory deprivation induces changes in visual perception, cognition and attention. While such changes in visual perception may act to compensate for a hearing loss, evidence suggests that these changes may also negatively influence adaptation to a cochlear implant. In this study, we investigated whether task demands influence attentional capture by salient visual stimuli in children who use a cochlear implant. Thirteen children with a cochlear implant (aged 8 – 16 years) and age-matched normally hearing children were presented with a rapid sequence of visual and auditory events. The participants’ task was to search for and identify numbers presented in a specified target colour, or to identify a change in the tonal frequency. Prior to each target a visual distractor was presented on one side of the central visual stream. Compared to trials in which the distractor was in a different colour to the target, or rotated on its axis, significant decrements in visual performance were found when the distractor was the same colour as the target. These contingent attentional capture effects did not differ between the groups. There was no difference across the visual distractor types or groups in performance on the auditory task. These results show that attentional capture by salient stimuli in proficient cochlear implant users depends on top-down attentional control settings, as it does in normally hearing children. The results therefore suggest that successful use of a cochlear implant is associated with normal attentional control and distractibility. Acknowledgements This work was supported by a Project Grant from the Garnette Passe and Rodney Williams Memorial Foundation. We gratefully acknowledge the Hear and Say Centre, Auchenflower, Brisbane, Australia for their assistance in recruiting children with a cochlear implant to take part in the study. Keywords: selective attention, contingent capture, cochlear implant, Visual Perception, Hearing Loss Conference: ACNS-2012 Australasian Cognitive Neuroscience Conference, Brisbane, Australia, 29 Nov - 2 Dec, 2012. Presentation Type: Poster Presentation Topic: Attention Citation: Kamke MR, Van Luyn J and Harris J (2012). Distractibility and top-down attentional control in children using a cochlear implant. Conference Abstract: ACNS-2012 Australasian Cognitive Neuroscience Conference. doi: 10.3389/conf.fnhum.2012.208.00154 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 10 Oct 2012; Published Online: 17 Nov 2012. * Correspondence: Dr. Marc R Kamke, The University of Queensland, The Queensland Brain Institute, St Lucia, Queensland, 4072, Australia, m.kamke@uq.edu.au Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Marc R Kamke Jeanette Van Luyn Jill Harris Google Marc R Kamke Jeanette Van Luyn Jill Harris Google Scholar Marc R Kamke Jeanette Van Luyn Jill Harris PubMed Marc R Kamke Jeanette Van Luyn Jill Harris Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

The effects of audiovisual task-set in visual search

We investigated whether top-down attentional control settings can specify task-relevant features in different sensory modalities (vision and audition). Two audiovisual search tasks were used where a spatially uninformative visual singleton cue preceded a target search array. In different blocks, participants searched for a visual target (defined by colour or shape in Experiments 1 and 2, respectively), or target defined by a combination of visual and auditory features (e.g., red target accompanied by a high-pitch tone). Spatial cueing effects indicative of attentional capture by target-matching visual singleton cues in the unimodal visual search task were reduced or completely eliminated when targets were audiovisually defined. The N2pc component (i.e. index attentional target selection in vision) triggered by these cues was reduced and delayed during search for audiovisual as compared to unimodal visual targets. These results provide novel evidence that the top-down control settings which guide attentional selectivity can include perceptual features from different sensory modalities.

Novelty and saliency in attentional capture by unannounced motion singletons

The present study examined attentional capture by an unannounced motion singleton in a visual search task. The results showed that a motion singleton only captured attention on its first unannounced occurrence when the observers had not encountered moving items before in the experiment, whereas it failed to capture when observers were familiar with moving items. This indicates that motion can capture attention independently of top-down attentional control settings, but only when motion as a feature is unexpected and new. An additional experiment tested whether salient items can capture attention when all stimuli possess new and unexpected features, and novelty information cannot guide attention. The results showed that attention was shifted to the location of the salient item when all items were new and unexpected, reinforcing the view that salient items receive attentional priority. The implications of these results for current theories of attention are discussed.

Target-uncertainty effects in attentional capture: Color-singleton set or multiple attentional control settings?

Previous spatial cuing studies have shown that the capture of spatial attention is contingent on top-down attentional control settings whose specificity varies as a function of the certainty of the defining features of the target. For example, when the target is a singleton defined by one specific color, observers adopt a control setting for that color. When the target can be one of two possible colors, however, observers appear to adopt a control setting for color singletons in general (see, e.g., Folk & Remington, 2008). The present study tested whether such results instead reflect the simultaneous maintenance of control settings for multiple colors (Adamo, Pun, Pratt, & Ferber, 2008). Observers searched for targets that were unpredictably red or green, preceded by spatial cues that were red, green, or blue. All three cue types produced evidence of capture, consistent with a general set for color singletons rather than the maintenance of multiple control settings.

Attentional capture by singletons is contingent on top-down control settings: Evidence from electrophysiological measures

The present study examined whether the capture of spatial attention is driven by stimulus salience (e.g., object uniqueness) or by a match to current attentional control settings (contingent capture). We measured the N2pc effect, a component of the event-related brain potential thought to reflect lateralized attentional allocation. On every trial, a noninformative cue display containing a colour singleton box was followed by a target display of letters. Participants searched for a target letter in a specified colour (in Experiments 1–3) or within a specified shape (in Experiment 4) while ignoring other stimuli. The key manipulation was whether the singleton cue contained the target-defining feature (e.g., a specific colour). Experiment 1 revealed signs of attention capture—a cue validity effect and an N2pc effect—only for singleton cues that contained the target-defining feature. This pattern persisted even when we increased the salience of the singleton box (Experiments 2 and 3). Irrelevant colour singletons also failed to produce a significant N2pc effect when the target was defined based on shape rather than colour (Experiment 4). We conclude that attention capture is strongly contingent on top-down attentional control settings, not bottom-up stimulus salience.

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.

Attentional control settings prevent abrupt onsets from capturing visual spatial attention

When a visual distractor appears earlier than a visual target in a target-detection task, response time is faster if the distractor appears at the same location as the target. When a visual distractor appears concurrently with a visual target in a target-detection task, response time is slowed relative to when no distractor is presented. Both effects have been taken as evidence of the capture of visual spatial attention, yet capture by early distractors is contingent on top-down attentional control settings (ACSs), and capture by concurrent distractors is not. The present study evaluated whether this incongruity is attributable to the timing of distractors (earlier than vs. concurrently with the target), or to the employed comparisons (same location/different location vs. distractor/no distractor). Using a task that presented both early and concurrent distractors, we observed that, regardless of timing, capture was contingent on ACSs when assessed by the same-location/different-location comparison. This result suggests that, although irrelevant stimuli cause nonspatial purely stimulus-driven effects, the capture of visual spatial attention is contingent on ACSs.

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.

Additivity of abrupt onset effects supports nonspatial distraction, not the capture of spatial attention

In a recent article, Schreij, Owens, and Theeuwes (2008) reported that abruptly onsetting distractors produce costs in performance even when spatial-cuing effects confirm the presence of a top-down set for color. The authors argued that these results show that abruptly onsetting new objects capture attention independent of a top-down set and, thus, provide conclusive evidence against the theory that attentional capture is contingent on top-down attentional control settings (Folk, Remington, & Johnston, 1992). In the following article, we argue that, contrary to the conclusion drawn by Schreij et al., their own data (1) disconfirm the claim that their abrupt onsets captured spatial attention and (2) are consistent with nonspatial interference accounts of singleton-distractor effects. In support of the nonspatial account, we show that in a paradigm similar to Schreij et al.'s, distractors that do not capture attention can nonetheless influence responses to a target. We conclude that the results of Schreij et al. do not represent a challenge to contingent capture theory.

Top-down control settings and the attentional blink: Evidence for nonspatial contingent capture

Previous studies have shown that spatial attention can be “captured” by irrelevant events, but only if the eliciting stimulus matches top-down attentional control settings. Here we explore whether similar principles hold for nonspatial attentional selection. Subjects searched for a coloured target letter embedded in an RSVP stream of letters inside a box centred on fixation. On critical trials, a distractor, consisting of a brief change in the colour of the box, occurred at various temporal lags prior to the target. In Experiment 1, the distractor produced a decrement in target detection, but only when it matched the target colour. Experiments 2 and 3 provide evidence that this effect does not reflect masking or the dispersion of spatial attention. The results establish that (1) nonspatial selection is subject to “capture”, (2) such capture is contingent on top-down attentional control settings, and (3) control settings for nonspatial capture can vary in specificity.