The influence of animal fear on attentional capture by fear-relevant animal stimuli in children

The present study demonstrated that pictures of fear-relevant animals, snakes and spiders, presented among backgrounds of other animal stimuli captured attention and interfered in the detection of a neutral target to the same extent in a large sample of unselected children (N=81). Moreover, detection of a neutral target animal was slowed more in the presence of a feared fear-relevant distracter, e.g., a snake for snake fearful children, than in the presence of a not feared fear-relevant distracter, e.g., a spider for snake fearful children. These results indicate attentional capture by phylogenetically fear-relevant animal stimuli in children and the selective enhancement of this effect by fear of these animals. These findings are consistent with current models of preferential processing of phylogenetically prepared threat stimuli and with cognitive models of anxiety that propose an enhancing effect of fear in the processing of fear-related stimuli.     

Role of frontal cortex in attentional capture by singleton distractors

The role of frontal cortex in selective attention to visual distractors was examined in an attentional capture task in which participants searched for a unique shape in the presence or absence of an additional colour singleton distractor. The presence of the additional singleton was associated with slower behavioural responses to the shape target, and a greater neural signal in inferior frontal gyrus. To investigate the involvement of cognitive control functions of the frontal lobes in the capture of attention by the additional singletons, we measured the effect of the additional singleton in a context of either low or high working memory load. Whereas behavioural capture was unaffected by the level of load on working memory, greater activity associated with the presence of the additional singleton was observed in inferior frontal gyrus, but only under high load. This effect was greater in participants who experienced greater capture. We argue that the role of inferior frontal gyrus in selective attention is to detect potential sources of distraction.     

An effective attentional set for a specific colour does not prevent capture by infrequently presented motion distractors

An organism's survival depends on the ability to rapidly orient attention to unanticipated events in the world. Yet, the conditions needed to elicit such involuntary capture remain in doubt. Especially puzzling are spatial cueing experiments, which have consistently shown that involuntary shifts of attention to highly salient distractors are not determined by stimulus properties, but instead are contingent on attentional control settings induced by task demands. Do we always need to be set for an event to be captured by it, or is there a class of events that draw attention involuntarily even when unconnected to task goals? Recent results suggest that a task-irrelevant event will capture attention on first presentation, suggesting that salient stimuli that violate contextual expectations might automatically capture attention. Here, we investigated the role of contextual expectation by examining whether an irrelevant motion cue that was presented only rarely (～3–6% of trials) would capture attention when observers had an active set for a specific target colour. The motion cue had no effect when presented frequently, but when rare produced a pattern of interference consistent with attentional capture. The critical dependence on the frequency with which the irrelevant motion singleton was presented is consistent with early theories of involuntary orienting to novel stimuli. We suggest that attention will be captured by salient stimuli that violate expectations, whereas top-down goals appear to modulate capture by stimuli that broadly conform to contextual expectations.     

Facial reactions to fear-relevant stimuli for subjects high and low in specific fear

This study was performed to investigate whether subjects high and low in fear of snakes react with different facial electromyographic (EMG) responses when exposed to snakes. Two groups of subjects were exposed to slides of snakes or flowers. After the experiment they rated their fear of snakes on a questionnaire and based on these ratings they were divided into high and low fear groups. Facial EMG was measured from the corrugator and zygomatic muscle regions. As predicted the high fear group reacted with a facial response interpretable as a negative emotional reaction whereas the low fear group did not. This difference was specific to snakes because high and low groups did not differ in responses to slides of flowers. The results are consistent with the proposition that facial EMG technique is a sensitive tool to distinguish reactions between subjects high and low in specific fears.     

In the grip of fear: Dissociations in attentional processing of animal fearful individuals

Using a modified attention paradigm we investigated specific attentional mechanisms in processing animal feared stimuli. In this paradigm arrays of four pictures were displayed and after its disappearance from view a probe (a letter, X or P) then followed unpredictably in the location of one of the four pictures. The results showed that discriminations of probes tended to be impeded by spider stimuli, compared to snake stimuli. This effect was potentiated by high anxiety but only for those individuals fearful of spiders, since no such effect was observed for snake fearful individuals. Moreover, the discrimination of the probes was not facilitated when presented after the feared stimuli. The implications of these findings are discussed as a function of the cognitive bias involved in specific fear.     

When something old becomes something new: spatiotemporal object continuity and attentional capture

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

Absence of attentional capture in parallel search is possible: A failure to replicate attentional capture in a non-singleton target search task

The notion of a singleton versus a feature search mode (Bacon & Egeth, 1994) in visual search is generally widely accepted. Yet Theeuwes (2004) claimed a different, potentially more parsimonious position. He suggested that the size of an attentional window is under top-down control and that salient distractors within this window capture attention. We report on four experiments. The first two experiments represent our various initial attempts to replicate the crucial Experiment 1 in the Theeuwes (2004) study, all of which were not successful. In Experiment 3, we showed that our distractor was able to yield attentional capture in a situation promoting the use of the singleton search mode (Bacon & Egeth, 1994). Experiment 4 was similar to Experiment 1 but incorporated further details that may account for the discrepant findings. Still, no attentional capture was found. In sum, it was not possible to replicate a crucial piece of evidence for the attentional window hypothesis, and our results are more consistent with the assumption of two different search modes.     

More capture,more suppression: Distractor suppression due to statistical regularities is determined by the magnitude of attentional capture

Salient yet irrelevant objects often interfere with daily tasks by capturing attention against our best interests and intentions. Recent research has shown that through implicit learning, distraction by a salient object can be reduced by suppressing the location where this distractor is likely to appear. Here, we investigated whether suppression of such high-probability distractor locations is an all-or-none phenomenon or specifically tuned to the degree of interference caused by the distractor. In two experiments, we varied the salience of two task-irrelevant singleton distractors each of which was more likely to appear in one specific location in the visual field. We show that the magnitude of interference by a distractor determines the magnitude of suppression for its high-probability location: The more salient a distractor, the more it becomes suppressed when appearing in its high-probability location. We conclude that distractor suppression emerges as a consequence of the spatial regularities regarding the location of a distractor as well as its potency to interfere with attentional selection.

     

Snakes and cats in the flower bed: fast detection is not specific to pictures of fear-relevant animals

The observation that snakes and spiders are found faster among flowers and mushrooms than vice versa and that this search advantage is independent of set size supports the notion that fear-relevant stimuli are processed preferentially in a dedicated fear module. Experiment 1 replicated the faster identification of snakes and spiders but also found a set size effect in a blocked, but not in a mixed-trial, sequence. Experiment 2 failed to find faster identification of snake and spider deviants relative to other animals among flowers and mushrooms and provided evidence for a search advantage for pictures of animals, irrespective of their fear relevance. These findings suggest that results from the present visual search task cannot support the notion of preferential processing of fear relevance.     

Blinded by emotion: target misses follow attention capture by arousing distractors in RSVP

Participants are usually able to search rapid serial visual presentation (RSVP) streams and report a single target, given that RSVP distractors do not typically deplete attention required for target identification. Here, participants performed single target search, but the target was preceded by a to-be-ignored distractor varying in valence and arousal. When the critical distractor was a sexual word, lower target accuracy was observed, particularly at short distractor-target stimulus onset asynchronies, even when participants were shown the critical distractors beforehand and told to ignore them. No reduction in target accuracy was evidenced when the critical distractor was negative, positive, threatening, or emotionally neutral. Target accuracy was predicted by participants' arousal ratings to the critical distractor words and by their memory for them, but not by their valence ratings. Memory for critical distractors mediated the relationship between arousal and target accuracy. The results provide evidence that arousing sexual words involuntarily capture attention and enter awareness at the expense of goal-driven targets, at least in the context of laboratory experiments performed by young university participants for whom sexual material might have high impact and relevance.     

Multiple states in visual working memory: Evidence from oculomotor capture by memory-matching distractors

Psychonomic Bulletin & Review - Visual working memory (VWM) representations interact with attentional guidance, but there is controversy over whether multiple VWM items simultaneously influence...     

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.     

Processing of distractors inside and outside the attentional focus in a priming procedure

A priming procedure was used to study the processing of distractors located either inside (between the location of two targets) or outside (peripherally to the locations of the targets) the focus of attention. The stimuli were five-letter arrays, and participants had to decide whether two marked target letters were the same or different. In Experiments 1 and 2, positive priming was obtained both when targets and in-distractors in primes repeated as targets in probes; negative priming was found when out-distractor primes repeated as targets in probes. In Experiment 3, we also manipulated the match in letter case from primes to probes. In-distractors produced reliable positive priming, irrespective of whether the letters matched in case. In contrast out-distractors produced negative priming but only when the letters had the same case in primes and probes. These results are attributed to a spatial attention process operating (in this case) on low-level visual features, and an object-based selection process that enables more abstract information to be processed for selected stimuli.     

On the automaticity of contingent capture: disruption caused by the attentional blink

Converging evidence has shown that onset capture can be completely eliminated by the demands of a concurrent task and during the attentional blink. In the present study, we investigated contingent capture during the attentional blink. We found that contingent capture was attenuated, or even completely eliminated, during the “blink” time of the attentional blink. These results indicate that contingent capture requires limited attentional resources.     

Exploring the modulation of attentional capture by attentional control settings using performance and illusory line motion

Modulation of attentional capture by attentional control settings was explored using performance and phenomenology. Trials began with four figure-8s presented above, below, left, and right of fixation. Any figure-8 (or none) brightened uninformatively (cue) before presentation of either a digit target (2 or 5 made from a figure-8 by deletion) calling for a speeded identification, or a line connecting adjacent figure-8s calling for a motion judgement. Such lines are seen drawn away from an adjacent cue. Digit targets appeared only on the horizontal or vertical axes, encouraging voluntary attention to two (target-relevant) of the four figure-8s. Whereas voluntary attention reduced attentional capture from cues at taskirrelevant locations (when lines were unlikely to be presented near the task-irrelevant locations), it had no effect on motion judgements, suggesting that cue-elicited exogenous attention affects perceptual arrival times while voluntary attention prioritizes locations for further processing without affecting arrival times.     

The relationship between self-reported animal fear and ERP modulation: Evidence for enhanced processing and fear of harmless invertebrates in snake- and spider-fearful individuals

The present study used ERPs to compare processing of fear-relevant (FR) animals (snakes and spiders) and non-fear-relevant (NFR) animals similar in appearance (worms and beetles). EEG was recorded from 18 undergraduate participants (10 females) as they completed two animal-viewing tasks that required simple categorization decisions. Participants were divided on a post hoc basis into low snake/spider fear and high snake/spider fear groups. Overall, FR animals were rated higher on fear and elicited a larger LPC. However, individual differences qualified these effects. Participants in the low fear group showed clear differentiation between FR and NFR animals on subjective ratings of fear and LPC modulation. In contrast, participants in the high fear group did not show such differentiation between FR and NFR animals. These findings suggest that the salience of feared-FR animals may generalize on both a behavioural and electro-cortical level to other animals of similar appearance but of a non-harmful nature.     

On the uniqueness of attentional capture by uninformative gaze cues: facilitation interacts with the Simon effect and is rarely followed by IOR.

Orienting to an uninformative peripheral cue is characterized by a brief facilitation followed by a long-lasting inhibition once attention is removed from the cued location. Although central gaze cues cause reflexive orienting, the inhibitory effect that is relatively ubiquitous following exogenous orienting to uninformative peripheral cues has been relatively rare. We hypothesized that IOR might be seen following gaze-induced orienting if attention were effectively returned to centre by a return gaze or return flash. The timecourse of gaze-directed orienting was measured by varying the interval between the gaze cue and a peripheral target requiring an orientation discrimination (permitting measurement of the Simon effect). Significant facilitation was observed at all but the longest SOA tested, 2,880 ms, by which time the facilitation had disappeared with no evidence of IOR. Gaze-induced cuing (which was unaffected by return cue condition) interacted with the Simon effect, decreasing it at the gazed-at location, a pattern that is not seen with more typical endogenous and exogenous cuing.     

Memory-based attentional capture by colour and shape contents in visual working memory

Current theories assume that there is substantial overlap between visual working memory (VWM) and visual attention functioning, such that active representations in VWM automatically act as an attentional set, resulting in attentional biases towards objects that match the mnemonic content. Most evidence for this comes from visual search tasks in which a distractor similar to the memory interferes with the detection of a simultaneous target. Here we provide additional evidence using one of the most popular paradigms in the literature for demonstrating an active attentional set: The contingent spatial orienting paradigm of Folk and colleagues. This paradigm allows memory-based attentional biases to be more directly attributed to spatial orienting. Experiment 1 demonstrated a memory-contingent spatial attention effect for colour but not for shape contents of VWM. Experiment 2 tested the hypothesis that the placeholders used for spatial cueing interfered with the shape processing, and showed that memory-based attentional capture for shape returned when placeholders were removed. The results of the present study are consistent with earlier findings from distractor interference paradigms, and provide additional evidence that biases in spatial orienting contribute to memory-based influences on attention.     

Negative attentional set in the attentional blink: control is not lost

The attentional blink (AB) refers to the finding that performance on the second of two targets (T1 and T2) in a rapidly presented stimulus stream is impaired when the targets are presented within 200-500 ms. This study investigates whether a negative attentional set, a form of top-down control, has an additional detrimental effect, and whether its influence is modulated by task demands. A negative attentional set was elicited through presentation of a pre-T1 distractor (D1), which belonged to the same category as T2. The presence of D1 impaired T2 performance, and this negative effect was generally larger inside than outside the AB. Moreover, this D1 effect remained constant or was augmented when the demand on T1 processing was enhanced. These findings demonstrate that a negative attentional set is maintained even though the central system is engaged in the in-depth processing of T1 during the AB.