Rewards shape attentional search modes

Visual attention can be configured for specific stimulus features (feature search mode) or it can be non-specifically set for salient pop-outs (singleton detection mode). Additionally, monetary rewards have been shown to bias attention toward specific features, but it is unknown whether secondary reinforcers (images of US$) can shape global attention via search modes. In a between-group study, we trained participants to value one search mode over the other. In a testing phase, a salient distractor captured the attention of the value-singleton group; however, the value feature group was completely unaffected. This suggests that rewards automatically bias global attention mechanisms and potentially mediate the handoff between stimulus-driven and goal-directed attentional control.     

Rapid allocation of temporal attention in the attentional blink paradigm

How fast can information of a first target (T1) in a rapid serial visual presentation be used for top-down allocation of attention in time? A valid cue about the temporal position of a second target (T2) was integrated into T1. The data show that 100 ms after T1 onset, T2 was identified better than without cue, raising the conditional T2 performance. T1 apparently triggers a facilitative effect of attention, known from other paradigms such as peripheral cueing.     

The role of space and time in object-based visual search

Recently we have provided evidence that observers more readily select a target from a visual search display if the motion trajectory of the display object suggests that the observer has dealt with it before. Here we test the prediction that this object-based memory effect on search breaks down if the spatiotemporal trajectory is disrupted. Observers searched a display for a target shape among multiple distractors. The entire search display then passed behind an occluder and reemerged in either the same or a different configuration. Experiment 1 shows that the same-object benefit for selection disappears whenever a spatial disruption is involved, but that it may survive a brief temporal disruption. Experiment 2 shows that with sufficiently long gaps, a temporal disruption also destroys the same-object benefit for selective attention. Experiment 3 demonstrates that the same-object effect is even stronger when there only is a very small probability that the target can be found at the same location as before. This also made the task sensitive to brief temporal disruptions. We conclude that a coherent spatiotemporal history of a display object supports the selection of its relevant subregions.     

The relationship between sustained attention,attentional selectivity,and capacity

The Theory of Visual Attention (TVA; Bundesen, 1990) provides a quantitative account of visual attentional selectivity and capacity but does not include a parameter relating to sustained attention. We conducted two studies to examine the relationship between sustained attention and the TVA parameters relating to selectivity and capacity. In the first study (n=46; mean age=41, SD=10), we investigated the effects of self alerting during a combined whole and partial report task (CombiTVA). In the second study, 70 participants (aged 20–69), performed the CombiTVA and the Sustained Attention to Response Task (Robertson, Manly, Andrade, Baddeley, & Yiend, 1997). The results indicated that attentional selectivity and capacity were unaffected by self alerting, unrelated to sustained attention ability and robust to the adverse effects of time-on-task. These findings are in keeping with the idea of independent functions relating to sustained attention and attentional selectivity and capacity.     

Multiple attentional sets while monitoring rapid serial visual presentations

The present study examined whether observers are able to establish multiple attentional sets to concurrently monitor two different spatial locations. Observers identified a target letter in red or cyan among nontarget letters of other heterogeneous colours during a temporal feature search. A peripheral distractor display consisted of one item of either the same colour as the current target, and the other potential target colour, or an irrelevant colour that could never be the target. They identified an odd-ball colour letter among homogenous colours during a singleton search. The results revealed that observers maintained multiple attentional sets for detecting two singletons or for targets involving two (or three) features. However, they were unable to maintain a mixture of sets. Moreover, exposure to a distractor containing feature that corresponded to a feature of the current target was advantageous for target identification. The presence or absence of this set-specific capture depended on top-down knowledge and did not occur automatically in the singleton-detection stream. These results demonstrate a limitation in the flexibility of attentional sets. Although two singleton detections were possible, multiple attentional templates for a more complex attentional set could not be maintained concurrently when monitoring multiple rapid serial visual presentations.     

Attentional capture within and between objects

The present study addressed the question whether attentional capture by abrupt onsets is affected by object-like properties of the stimulus field. Observers searched for a target circle at one of four ends of two solid rectangles. In the focused attention condition the location of the upcoming target was cued by means of a central arrowhead, whereas in the divided attention condition, the target location was not cued. Irrelevant abrupt onsets could appear either within the attended or within the non-attended object. The results showed that in the focused attention condition, onsets ceased to capture attention irrespective of whether the onset appeared within an attended object or within a non-attended object.     

Altering attentional control settings causes persistent biases of visual attention

Attentional control settings have an important role in guiding visual behaviour. Previous work within cognitive psychology has found that the deployment of general attentional control settings can be modulated by training. However, research has not yet established whether long-term modifications of one particular type of attentional control setting can be induced. To address this, we investigated persistent alterations to feature search mode, also known as an attentional bias, towards an arbitrary stimulus in healthy participants. Subjects were biased towards the colour green by an information sheet. Attentional bias was assessed using a change detection task. After an interval of either 1 or 2 weeks, participants were then retested on the same change detection task, tested on a different change detection task where colour was irrelevant, or were biased towards an alternative colour. One experiment included trials in which the distractor stimuli (but never the target stimuli) were green. The key finding was that green stimuli in the second task attracted attention, despite this impairing task performance. Furthermore, inducing a second attentional bias did not override the initial bias toward green objects. The attentional bias also persisted for at least two weeks. It is argued that this persistent attentional bias is mediated by a chronic change to participants’ attentional control settings, which is aided by long-term representations involving contextual cueing. We speculate that similar changes to attentional control settings and continuous cueing may relate to attentional biases observed in psychopathologies. Targeting these biases may be a productive approach to treatment.     

Beyond inattentional blindness and attentional misdirection: From attentional paradigms to attentional mechanisms

Memmert (2010) tried to foster the development of attentional research by discussing four differences between attentional misdirection (AM) and inattentional blindness (IB). Considering this goal, the comment was received in the intended way by the comments of (Most, 2010) and (Moran and Brady, 2010) who make a number of highly valuable suggestions for further progress. As initially suggested by Memmert (2010) this dialog should help unravel the underlying attentional mechanisms of different paradigms. Therefore, we first discuss the suggested distinction between central and spatial IB by Most (2010). Second, we argue that working memory and perceptual load research seem particularly interesting in this regard and should be taken into consideration when conducting future research along the lines of IB and AM. Third, representative task designs can be an important mosaic piece in across-the-board attention theories and highly useful for deriving further testable hypothesis in naturalistic settings. The most important claim of all commentaries in this issue is that the proposed ideas can all be empirically tested and thereby contribute to the advancement of an unified theoretical framework incorporating IB, AM in consideration of overt and covert attention mechanisms.     

Attentional prioritisation of threatening information: Examining the role of the size of the attentional window

In line with most models of emotion, research has shown that threatening information receives attentional priority over neutral information. Recently, it has been suggested that the degree to which participants divide their attention across the visual field (the attentional window) may modulate the extent to which salient objects are attentionally prioritised. In the current study, participants were required to identify a target inside one of a variable number of coloured circles. One colour (Conditioned Stimulus, CS +) was fear-conditioned using an electrocutaneous stimulus at tolerance level. This search task was combined with a go/no-go task that required participants to either divide attention across the visual field to create a broad attentional window (global group), or focus their attention on the fixation point to create a narrow attentional window (local group). The results showed that only in the global group was the CS + colour prioritised over the neutral colours, indicating that a broader attentional window leads to enhanced attentional prioritisation of threat. Implications for research on attentional bias to threat are discussed.     

Your divided attention, please! The maintenance of multiple attentional control sets over distinct regions in space

When non-informative peripheral cues precede a target defined by a specific feature, cues that share the critical feature will capture attention while cues that do not will be effectively ignored. We tested whether different attentional control sets can be simultaneously maintained over distinct regions of space. Participants were instructed to respond only to specific colored targets at specific locations. Most trials included non-predictive cues whose location and/or color were either congruent or incongruent with the spatial and/or color properties of the impending target. We observed contingent capture only for cues that were consistent with the attentional control set applied to that region of space. This is the first demonstration that separate attentional control sets can be simultaneously maintained at distinct spatial locations, with implications for the flexibility of endogenous control over automatic attentional orienting.     

Ageing and attentional control

The research examines the structural bottleneck account and the resource account of the substantial dual-task deficits among older adults. Procedures from two common dual-task methodologies—the psychological refractory period and the relative-priority manipulation—were used to encourage maximization of the joint performance. Performance and time-sharing strategies from subjects between the ages of 20 and 70 years were examined. Age-related declines in time-sharing efficiency and in the precision of the executive control process were observed. The age-related effect was larger when two manual responses were required than when one manual and one vocal response were required, but no evidence for obligatory sequential processing was found. Except for the most demanding conditions, comparable practice effects were observed between the younger and older subjects, suggesting considerable cognitive plasticity in the older subjects. Implications for the two attentional accounts were discussed.     

The interacting effect of load and space on visual selective attention

In the study of visual attention, two major determinants of our ability to ignore distracting information have been isolated, namely, (1) the spatial separation from the focus of attention and (2) perceptual load. This study manipulated both factors using a dual-task adaptation of the flanker paradigm (Eriksen & Hoffman, 1973). It showed that (1) although attention followed a gradient profile under low perceptual load it followed a Mexican-hat profile under high perceptual load, consistent with the idea that increasing load focuses spatial attention; and (2) increasing perceptual load did not improve overall selectivity: Though selectivity improved at near separations, it was impaired at far ones. Load and spatial separation exert interacting effects.     

And along came a spider: An attentional bias for the detection of spiders in young children and adults

Spiders are among the most common targets of fears and phobias in the world. In visual search tasks, adults detect their presence more rapidly than other kinds of stimuli. Reported here is an investigation of whether young children share this attentional bias for the detection of spiders. In a series of experiments, preschoolers and adults were asked to find the single spider picture among an array of eight mushrooms or cockroaches or the reverse. Both children and adults detected the presence of spiders more rapidly than both categories of distracter stimuli. Furthermore, there was no difference between the detection of two neutral stimuli (cockroaches vs. mushrooms). These results provide the first evidence of enhanced visual detection of spiders in young children.     

Attentional capture by emotional faces is contingent on attentional control settings

Attentional capture by schematic emotional faces was investigated in two experiments using the flanker task devised by Eriksen and Eriksen (1974). In Experiment 1, participants were presented with a central target (a schematic face that was either positive or negative) flanked by two identical distractors, one on either side (schematic faces that were positive, negative, or neutral). The objective was to identify the central target as quickly as possible. The impact of the flankers depended on their emotional expression. Consistent with a threat advantage hypothesis (negative faces are processed faster and attract more processing resources), responses to positive faces were slower when these were flanked by (response incompatible) negative faces as compared with positive or neutral faces, whereas responses to negative faces were unaffected by the identity of the flankers. Experiment 2 was a standard flanker task with letter stimuli except that the task-neutral flankers were schematic faces that were either positive, negative, or emotionally neutral. In this case, in which faces and emotional expressions were to be ignored, performance seemed entirely unaffected by the faces. This result suggests that attentional capture by emotional faces is contingent on attentional control settings.     

Sustained perceptual invisibility of solid shapes following contour adaptation to partial outlines

Contour adaptation (CA) is a recently described paradigm that renders otherwise salient visual stimuli temporarily perceptually invisible. Here we investigate whether this illusion can be exploited to study visual awareness. We found that CA can induce seconds of sustained invisibility following similarly long periods of uninterrupted adaptation. Furthermore, even fragmented adaptors are capable of producing CA, with the strength of CA increasing monotonically as the adaptors encompass a greater fraction of the stimulus outline. However, different types of adaptor patterns, such as distinctive shapes or illusory contours, produce equivalent levels of CA suggesting that the main determinants of CA are low-level stimulus characteristics, with minimal modulation by higher-order visual processes. Taken together, our results indicate that CA has desirable properties for studying visual awareness, including the production of prolonged periods of perceptual dissociation from stimulation as well as parametric dependencies of that dissociation on a host of stimulus parameters.     

Subjective discriminability of invisibility: A framework for distinguishing perceptual and attentional failures of awareness

Conscious visual perception can fail in many circumstances. However, little is known about the causes and processes leading to failures of visual awareness. In this study, we introduce a new signal detection measure termed subjective discriminability of invisibility (SDI) that allows one to distinguish between subjective blindness due to reduction of sensory signals or to lack of attentional access to sensory signals. The SDI is computed based upon subjective confidence in reporting the absence of a target (i.e., miss and correct rejection trials). Using this new measure, we found that target misses were subjectively indistinguishable from physical absence when contrast reduction, backward masking and flash suppression were used, whereas confidence was appropriately modulated when dual task, attentional blink and spatial uncertainty methods were employed. These results show that failure of visual perception can be identified as either a result of perceptual or attentional blindness depending on the circumstances under which visual awareness was impaired.     

Psychoticism and attentional flexibility

In three separate experiments, we tested the hypothesis that a systematic relationship between psychoticism (P) and visual selective attention is infrequently observed because the tasks typically used to test individual differences in efficiency of attentional mechanisms do not entail attentional flexibility. We manipulated the selection rule of the computerized divided visual attention (DIVA) task to be either (a) a predictable, or (b) a random manner, and a secondary task was added to check the quality of high P scorers’ performance in an interference condition; and we also introduced breaks between DIVA tasks to allow for cue utilization. Results revealed that low P scorers outperformed high P scorers in the regular selection rule alternation condition (cue utilization possible), whereas high P scorers performed better in random alternation condition – high P scorers also showed performance superiority in the dual task condition unless stimuli presentation was speeded up. Thus, P does not necessarily impair attentional performance; indeed, our data point to performance advantages of high P, especially attentional efficiency in tasks requiring small demands of attentional control.     

The role of attention level in the attentional boost effect

ABSTRACT

Previous studies reported a memory facilitation effect in which increased attention to one task facilitates the memory performance on another. Here we examined the characteristics of this “attentional boost effect” (ABE), and demonstrated how attention level during memory encoding influences the ABE strength by changing the occurring frequency of the attention-engaging target signal relative to the non-attention-engaging distractor signal (Experiment 1), and the physical salience of colour of the target signal (Experiment 2). The results indicated stronger ABE in conditions with a low ratio of target signal trials and with a salient target signal. Experiment 3 examined the role of spatial attention, which sought to measure how the distance between the target signal and the to-be-encoded item would influence the ABE strength. The results showed that the ABE strength was not influenced by the distance between the two. Overall, these findings suggest ABE may be mainly based on temporal attention.