Memory-driven Attentional Capture Research Articles

Multisensory Enhancement of Cognitive Control over Working Memory Capture of Attention in Children with ADHD.

Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder in school-age children. Although it has been well documented that children with ADHD are associated with impairment of executive functions including working memory (WM) and inhibitory control, there is not yet a consensus as to the relationship between ADHD and memory-driven attentional capture (i.e., representations in WM bias attention toward the WM-matched distractors). The present study herein examined whether children with ADHD have sufficient cognitive control to modulate memory-driven attentional capture. 73 school-age children (36 with ADHD and 37 matched typically developing (TD) children) were instructed to perform a visual search task while actively maintaining an item in WM. In such a paradigm, the modality and the validity of the memory sample were manipulated. The results showed that under the visual WM encoding condition, no memory-driven attentional capture was observed in TD children, but significant capture was found in children with ADHD. In addition, under the audiovisual WM encoding condition, memory-matched distractors did not capture the attention of both groups. The results indicate a deficit of cognitive control over memory-driven attentional capture in children with ADHD, which can be improved by multisensory WM encoding. These findings enrich the relationship between ADHD and cognitive control and provide new insight into the influence of cross-modal processing on attentional guidance.

Enhanced memory-driven attentional capture in action video game players

Action video game players (AVGPs) have been shown to have an enhanced cognitive control ability to reduce stimulus-driven attentional capture (e.g., from an exogenous salient distractor) compared with non-action video game players (NVGPs). Here we examined whether these benefits could extend to the memory-driven attentional capture (i.e., working memory (WM) representations bias visual attention toward a matching distractor). AVGPs and NVGPs were instructed to complete a visual search task while actively maintaining 1, 2 or 4 items in WM. There was a robust advantage to the memory-driven attentional capture in reaction time and first eye movement fixation in the AVGPs compared to the NVGPs when they had to maintain one item in WM. Moreover, the effect of memory-driven attentional capture was maintained in the AVGPs when the WM load was increased, but it was eliminated in the NVGPs. The results suggest that AVGPs may devote more attentional resources to sustaining the cognitive control rather than to suppressing the attentional capture driven by the active WM representations.

Opposing effects of stimulus-driven and memory-driven attention in visual search

A recent study (Jung, Han, & Min, in press) reported that the extent to which attentional control is strained is a critical factor for observing stimulus-driven attentional capture in visual search. Expanding this study, we tested whether memory-driven attentional capture is also dependent on cognitive mechanism underlying visual search tasks. In our experiment, a group of participants performed a dual task, consisting of a working memory and a visual search task (memory-driven attention group), whereas the other performed only a visual search task (stimulus-driven attention group). Each group was further divided into two groups depending on the search task performed. For visual search tasks, we utilized two different search tasks; Landolt-C and orientation feature search tasks. For the former, participants searched for an outlined square with a top- or bottom-gap among left- or right-gap squares. For the latter, participants looked for a right- or left-tilted line among vertical lines. In a half of the total trials, a memory-matching/salient singleton distractor was present. In the remaining trials, no such a memory-matching/singleton distractor was present. As results, attentional capture by the singleton distractor was found under feature search task, p< .01. On the contrary, the task-irrelevant distractor did not capture when participants performed the Landolt-C search, p> .45. The memory-driven group showed a different pattern. A task-irrelevant, memory matching distractor captured attention when participants performed Landolt-C search task, p< .001. However, no memory-driven attentional capture was found under the feature search, p > .72. Our results demonstrate that the nature underlying visual search tasks is an important factor for observing both stimulus-driven and memory-driven attention. However, the specific patterns of the capture were opposite. These findings point to the role of interplay between the extent to which attentional control is strained and working memory in attentional capture.

How robust and rapid can the memory-driven attentional capture be?

Previous research has indicated that visual attention can be automatically captured by sensory inputs that match the contents of visual working memory. Furthermore, the information in visual working memory can be used as a template of memory guidance for either the selection or rejection of visual attention. The current study investigated the memory-driven attentional processes in four experiments which extend and complement previous research. Participants performed a visual search task while maintaining items in visual working memory. Experiment 1 used an arrow as a pre-cue indicating which side of the screen the search target would appear on. Experiment 2 used two circles as pre-cues for the right-up/down location of the search target. Experiment 3 presented a memory-matching distractor for 300 ms followed by a blank screen. Experiment 4 presented a memory-matching distractor for 150 ms followed by the visual search task. All experiments resulted in significantly slower visual search reaction times (RTs) for the invalid condition (memory-matching distractor) compared to the neutral condition but with no significant differences in memory performance. This result suggests that the contents of working memory affect the deployment of attention in visual search. Our findings show that attentional capture occurs even within short periods of 150 ms, which demonstrates the robustness and speed of memory-driven attentional processes. Consequently, attentional capture appears to be initiated at an early phase of visual processing but can be strategically inhibited through cognitive control at later stages of analysis.

Working Memory-Driven Attention in Real-World Search.

People's attention is well attracted to stimuli matching their working memory. This memory-driven attentional capture has been demonstrated in simplified and controlled laboratory settings. The present study investigated whether working memory contents capture attention in a setting that closely resembles real-world environment. In the experiment, participants performed a task of searching for a target object in real-world indoor scenes, while maintaining a visual object in working memory. To create a setting similar to real-world environment, images taken from IKEA®'s online catalogue were used. The results showed that participants' attention was biased toward a working memory-matching object, interfering with the target search. This was so even when participants did not expect that a memory-matching stimulus would appear in the search array. These results suggest that working memory can bias attention in complex, natural environment and this memory-driven attentional capture in real-world setting takes place in an automatic manner.

Memory-driven attentional capture reveals the waxing and waning of working memory activation due to dual-task interference.

Previous studies have shown that information held in working memory (WM) actively or as a residue of previous processing can lead to attentional capture by corresponding stimuli in the environment. Here, we compared attentional capture by goal-driven and residual WM activation and examined how these effects are affected by dual-task interference. In two experiments, participants performed an animacy judgment task for a word that they did or did not have to remember for a later recognition test. The word was followed in half of the trials by an arithmetic task that served to disrupt the WM activation of the previously processed word. Subsequently, WM-driven capture was assessed by having participants perform a single-target rapid serial visual presentation task in which a line drawing corresponding to the word was presented shortly before a target. The results showed that the line drawing captured attention irrespective of the presence of the arithmetic task when the word had to be remembered. In comparison, the animacy judgment alone resulted in capture only when the arithmetic task was absent, and this effect was equally strong as the capture effect caused by a to-be-remembered word. Taken together, these findings show that although residual and goal-driven WM activation may be equally potent in guiding attentional selection, these two forms of WM activation differ in that residual activation is overwritten by an attention-demanding task, whereas goal-driven WM activation can lead to the reinstatement of a stimulus after performing such a task.

Object-based Encoding in Visual Working Memory: Evidence from Memory-driven Attentional Capture.

Visual working memory (VWM) adopts a specific manner of object-based encoding (OBE) to extract perceptual information: Whenever one feature-dimension is selected for entry into VWM, the others are also extracted. Currently most studies revealing OBE probed an ‘irrelevant-change distracting effect’, where changes of irrelevant-features dramatically affected the performance of the target feature. However, the existence of irrelevant-feature change may affect participants’ processing manner, leading to a false-positive result. The current study conducted a strict examination of OBE in VWM, by probing whether irrelevant-features guided the deployment of attention in visual search. The participants memorized an object’s colour yet ignored shape and concurrently performed a visual-search task. They searched for a target line among distractor lines, each embedded within a different object. One object in the search display could match the shape, colour, or both dimensions of the memory item, but this object never contained the target line. Relative to a neutral baseline, where there was no match between the memory and search displays, search time was significantly prolonged in all match conditions, regardless of whether the memory item was displayed for 100 or 1000 ms. These results suggest that task-irrelevant shape was extracted into VWM, supporting OBE in VWM.

Working memory contents revive the neglected, but suppress the inhibited

It is well known that attention is biased toward a stimulus matching working memory contents. However, it remains unknown whether the maintenance of information in working memory by itself is sufficient to create memory-driven attentional capture. Notably, in many previous studies showing the memory-driven attentional capture, the task settings might have explicitly or implicitly incentivized participants to strategically attend to a memory-matching stimulus. By innovating an experimental paradigm, the present study overcame this challenge and directly tested whether working memory contents capture attention in the absence of task-level attentional bias toward a memory-matching stimulus. I found that a stimulus that is usually outside the focus of attention, powerfully captured attention when it matched working memory contents, whereas a match between working memory and an inhibited stimulus suppressed attentional allocation toward the memory-matching stimulus. These findings suggest that in the absence of any task-level attentional bias toward memory-matching stimuli, attention is biased toward a memory-matching stimulus, but this memory-driven attentional capture is diminished when top-down inhibition is imposed on the stimulus.

The role of depth of encoding in attentional capture.

The aim of the current study was to examine whether depth of encoding influences attentional capture by recently attended objects. In Experiment 1, participants first had to judge whether a word referred to a living or a nonliving thing (deep encoding condition) or whether the word was written in lower- or uppercase (shallow encoding condition), and they then had to identify a digit displayed midway in a rapid serial visual presentation (RSVP) stream of 8 pictures. A picture corresponding to the previously processed word was presented either before or after the target digit. The results showed that this picture captured attention, thus resulting in an attentional blink for identification of a target digit, in the deep encoding condition but not in the shallow encoding condition. In Experiment 2, this capture effect was found to be abolished when an additional working-memory (WM) task was performed directly after the word-judgment task, suggesting that the capture effect stemmed from residual WM activation that could be erased by means of a secondary WM task. Taken together, these results suggest that deep and shallow encoding result in different degrees of WM activation, which in turn influences the likelihood of memory-driven attentional capture.

The Priority of Color in Working-Memory-Driven Ocular Capture

The target template maintaining in working memory can guide attention bias to target-like items in the visual scene facilitating the visual search. In addition to the target template, representations in worming memory that are irrelevant to the search target have also been shown to guide attention in a top-down way. During visual search, the distractor sharing attributes with the online working memory representations capture more attention than other distractors, displaying a robust memory-driven attentional capture effect. However, not all stimulus attributes of the working memory representations are equal effective in capturing attention, previous studies showed that the color attribute of a memory-matched distractor was more effective in capturing the first fixation than the shape attribute. According to the opinion of Wolfe and Horowitz(2004), the color attribute was one of the "undoubted guiding attributes" that had greater efficiency for attention guidance than the shape attribute. So it is unclear yet whether color still has such priority when directly competing against the orientation attribute that is also one of the "undoubted guiding attributes". Three experiments using the classic dual task paradigm were reported here to address this issue. In Experiment 1, participants were asked to search for a specific target accompanied with a distractor which was always located in the opposite visual field of the target. The target and the distractor were respectively embedded in the bar with color and/or orientation attributes same to or different from the objects held in the working memory. The results suggested that the bar would capture more first fixations(i.e. ocular capture effect) only when it shared color attribute with the memory items than when it did not, most importantly, the color-matched bar still captured more first fixations than the orientation-matched bar while they simultaneously appeared and directly competed for attention. In Experiment 2 and 3, participants were required to search either color or orientation of the remembered object. The results showed that in the color search task, ocular capture occurred when the color attributes of the target matched the remembered object regardless of the orientation attribute. However, in the orientation search task, ocular capture still occurred when the distractor was of the same color as the remembered object and slowed down search. These asymmetric results again demonstrated the priority of color attribute in the working memory representation. In conclusion, these results indicate that attentional priority could modulate attentional guidance from working memory, and the color attribute is of greater attentional priority for ocular capture than orientation.

Role of attentional tags in working memory-driven attentional capture.

Recent studies have demonstrated that the contents of working memory capture attention when performing a visual search task. However, it remains an intriguing and unresolved question whether all kinds of items stored in working memory capture attention. The present study investigated this issue by manipulating the attentional tags (target or distractor) associated with information maintained in working memory. The results showed that working memory-driven attentional capture is a flexible process, and that attentional tags associated with items stored in working memory do modulate attentional capture. When items were tagged as a target, they automatically captured attention; however, when items were tagged as a distractor, attentional capture was reduced.

Memory-driven attentional capture is modulated by temporal task demands

Previous research has shown that attention is biased towards items that match the current content of working memory (memory-driven attentional capture), but it remains unclear whether this effect is automatic or under voluntary control. Participants memorized a colour for subsequent recall and searched for a target shape among distractors that included a colour singleton which matched or mismatched the memorized colour. Search displays were presented for 200 ms or until response execution. Display duration was blocked or randomly intermixed for different participants. Reaction times (RTs) were slower on trials with memory-matching distractors, reflecting memory-driven attentional capture. Only with blocked display durations, this effect was much smaller for short than for long displays. This demonstrates that attention tasks are prioritized and shielded from interactions with working memory when this is required by high temporal task demands, and suggests that memory-driven attentional capture is controlled by top-down processing strategies.

The top-down control of visual selection and how it is linked to the N2pc component

Is the spatial selection of visual objects fully under the control of top-down factors such as current tasks sets? In his admirably clear and systematic review (Theeuwes, 2010), Jan Theeuwes claims that the selection of visual objects is determined solely by bottom-up mechanisms that are independent of observers' selection intentions, and that top-down control only comes into play at later stages of attentional processing. His argument starts with the assumption that visual information is initially processed in a parallel and feedforward fashion, and that this early stage is entirely stimulus-driven. That much is not contentious — in fact, many models of visual processing and attentional selectivity assume the existence of an early fast feedforward sweep that is essentially non-selective. Theeuwes' central and controversial claim concerns the factors that drive the subsequent attentional selection of visual objects. He argues that this selection is determined by bottom-up salience maps that are computed during the initial parallel visual processing stage. Crucially, this salience-driven attentional object selection cannot be prevented or even modulated by top-down task set. Top-down factors can only influence what happens after an object has been selected; for example, attention can be rapidly disengaged from objects that do not possess currently task-relevant attributes. But intentional factors have no role whatsoever in the attentional selection of visual objects. It is unusual to define a psychological concept (bottom-up visual selection) by applying a negative criterion (the absence of intentional modulation). As a result, there is a surprisingly wide range of cases that appear to meet this criterion. For example, Theeuwes considers phenomena such as intertrial feature priming or memory-driven attentional capture to be instances of bottom-up selection, even though here the selection of visual objects is not determined by their salience. Such an extension of the concept of bottom-up selection

What drives memory-driven attentional capture?

What drives memory-driven attentional capture?

Subliminally Presented and Stored Objects Capture Spatial Attention

When objects disappear from view, we can still bring them to mind, at least for brief periods of time, because we can represent those objects in visual short-term memory (VSTM) (Sperling, 1960; Cowan, 2001). A defining characteristic of this representation is that it is topographic, that is, it preserves a spatial organization based on the original visual percept (Vogel and Machizawa, 2004; Astle et al., 2009; Kuo et al., 2009). Recent research has also shown that features or locations of visual items that match those being maintained in conscious VSTM automatically capture our attention (Awh and Jonides, 2001; Olivers et al., 2006; Soto et al., 2008). But do objects leave some trace that can guide spatial attention, even without participants intentionally remembering them? Furthermore, could subliminally presented objects leave a topographically arranged representation that can capture attention? We presented objects either supraliminally or subliminally and then 1 s later re-presented one of those objects in a new location, as a "probe" shape. As participants made an arbitrary perceptual judgment on the probe shape, their covert spatial attention was drawn to the original location of that shape, regardless of whether its initial presentation had been supraliminal or subliminal. We demonstrate this with neural and behavioral measures of memory-driven attentional capture. These findings reveal the existence of a topographically arranged store of "visual" objects, the content of which is beyond our explicit awareness but which nonetheless guides spatial attention.

What drives memory-driven attentional capture? The effects of memory type, display type, and search type.

An important question is whether visual attention (the ability to select relevant visual information) and visual working memory (the ability to retain relevant visual information) share the same content representations. Some past research has indicated that they do: Singleton distractors interfered more strongly with a visual search task when they were identical or related to the object held in memory. However, other research has failed to find such effects despite using very similar procedures. The present study, using the same combined working memory and attentional capture paradigm, demonstrates which factors do (varied mapping, low stimulus energy) and which factors do not (exact type of visual memory method used, difficult nature of search, heterogeneity of displays, and instruction) contribute to this discrepancy.

Feature-based memory-driven attentional capture: Visual working memory content affects visual attention.

In 7 experiments, the authors explored whether visual attention (the ability to select relevant visual information) and visual working memory (the ability to retain relevant visual information) share the same content representations. The presence of singleton distractors interfered more strongly with a visual search task when it was accompanied by an additional memory task. Singleton distractors interfered even more when they were identical or related to the object held in memory, but only when it was difficult to verbalize the memory content. Furthermore, this content-specific interaction occurred for features that were relevant to the memory task but not for irrelevant features of the same object or for once-remembered objects that could be forgotten. Finally, memory-related distractors attracted more eye movements but did not result in longer fixations. The results demonstrate memory-driven attentional capture on the basis of content-specific representations.