Threat-relevant Stimuli Research Articles

Attentional bias to threat is modulated by stimulus content: an fNIRS study.

People are evolutionarily predisposed to associate threat relevant stimuli with fear or aversiveness and show an attentional bias toward threat. Attentional bias modification (ABM) has been shown to reduce threat biases, while quantitative reviews assessing the effectiveness of bias modification yielded inconsistent results. The current study examined the relationship between the training effect of attentional bias to threat and the type of threatening stimuli. Twenty-two participants performed a modified dot-probe task while undergoing functional near-infrared spectroscopy (fNIRS) imaging. Results indicated that there was a strong pattern of attentional avoidance among individuals in an animal but not human threat condition. Furthermore, findings from fNIRS confirmed that the influence from type of threatening stimulus would be modulated by cortical activation patterns, especially in the ventrolateral prefrontal cortices (vlPFC) and angular gyrus. Overall, these results suggest that stimulus-specific may play a major role in personalization of specific psychological interventions.

C-reactive protein moderates associations between racial discrimination and ventromedial prefrontal cortex activation during attention to threat in Black American women.

Prior research has shown that racial discrimination (RD) impacts activation in threat network regions, including the ventromedial prefrontal cortex (vmPFC) and middle occipital cortex during attention to threat-relevant stimuli. However, little is known about the biological mechanisms that may modulate these effects; inflammation may be a pathway linking RD and threat network activation. As such, the current study aimed to explore whether systemic inflammation, measured by C-reactive protein (CRP) levels, may moderate the relationship between RD and activation in the vmPFC and middle occipital cortex during attention to threat. Blood samples for inflammatory marker (CRP) assays were obtained from forty Black American women (mean [SD] age, 39.93 [9.97] years; range, 22-58 years) recruited from an ongoing trauma study; participants also viewed threat-relevant stimuli as part of an attention task during fMRI. We found that CRP moderated the relationship between RD and vmPFC activation during attention to threat, such that participants with relatively higher concentrations of CRP ( ≥ 23.97 mg/L) demonstrated significant positive associations between RD and vmPFC activation [β = 0.18, CI (0.04, 0.32), t = 2.65, p = 0.01]. No significant associations were observed for participants who showed moderate (10.89 mg/L) or low (0.20 mg/L) CRP concentrations. CRP did not moderate the relationship between RD and middle occipital cortex activation. Our data present a mechanism through which RD may influence immune system activation and, in turn, threat networkactivation. Inflammation may contribute to brain health vulnerabilities in Black Americans via its effects on threat circuits; this merits further investigation in large-scale studies.

Civilian Moral Injury and Amygdala Functional Connectivity During Attention to Threat

BackgroundMoral injury references emotional and spiritual/existential suffering that may emerge following psychological trauma. Despite being linked to adverse mental health outcomes, little is known about the neurophysiological mechanisms of this phenomenon. In this study, we examined neural correlates of moral injury exposure and distress using the Moral Injury Exposure and Symptom Scale for Civilians. We also examined potential moderation of these effects by race (Black vs. White individuals) given the likely intersection of race-related stress with moral injury. MethodsForty-eight adults ages 18 to 65 years (mean age = 30.56, SD = 11.93) completed the Moral Injury Exposure and Symptom Scale for Civilians and an affective attentional control measure, the affective Stroop task (AS), during functional magnetic resonance imaging; the AS includes presentation of threat-relevant and neutral distractor stimuli. Voxelwise functional connectivity of the bilateral amygdala was examined in response to threat-relevant versus neutral AS distractor trials. ResultsFunctional connectivity between the right amygdala and left postcentral gyrus/primary somatosensory cortex was positively correlated with the Moral Injury Exposure and Symptom Scale for Civilians exposure score (voxelwise p < .001, cluster false discovery rate–corrected p < .05) in response to threat versus neutral AS distractor trials. Follow-up analyses revealed significant effects of race; Black but not White participants demonstrated this significant pattern of amygdala–left somatosensory cortex connectivity. ConclusionsIncreased exposure to potentially morally injurious events may lead to emotion-somatosensory pathway disruptions during attention to threat-relevant stimuli. These effects may be most potent for individuals who have experienced multilayered exposure to morally injurious events, including racial trauma. Moral injury appears to have a distinct neurobiological signature that involves abnormalities in connectivity of emotion-somatosensory paths, which may be amplified by race-related stress.

How preschoolers perceive danger – A study of inattentional bias

ABSTRACT Harmful threats can sometimes appear unexpectedly in the lives of young children, whose limited experience leads to a greater risk of endangerment. The current study adapted the Variant Odd Ball protocol to explore the effects of threat and familiarity on inattentional blindness (IB). This research evaluated reactions to presentations of evolutionarily relevant images such as millipedes, snakes, escargots, and snails, compared with reactions to evolutionarily irrelevant images such as syringes, knives, flashlights, and spoons. Respondents included three hundred and forty 4–5-year-old preschool children. The findings were as follows: (1) The property of familiarity plays an important role in preschool children’s IB to both evolutionarily relevant and irrelevant images, and highly familiar images were easier to detect than less familiar images; (2) the manipulation of images showed that the threat-relevant stimuli were not more likely to be detected than the non-threat-relevant stimuli; (3) no significant difference was found between the detection rates of evolutionarily relevant and irrelevant images. Preschool children have a lower detection rate of threat-relevant images (e.g., snake, knife) which may reflect their limited experience of danger and weaker integration of these threat-relevant images in the current study.

Association of Racial Discrimination With Neural Response to Threat in Black Women in the US Exposed to Trauma

Racial discrimination has a clear impact on health-related outcomes, but little is known about how discriminatory experiences are associated with neural response patterns to emotionally salient cues, which likely mediates these outcomes. To examine associations of discriminatory experiences with brainwide response to threat-relevant cues in trauma-exposed US Black women as they engage in an attentionally demanding task. A cross-sectional study was conducted from May 1, 2014, to July 1, 2019, among 55 trauma-exposed US Black women to examine associations of racial discrimination experiences with patterns of neural response and behavior to trauma-relevant images in an affective attentional control task. Posttraumatic stress disorder (PTSD) symptoms and trauma exposure were entered as covariates to isolate variance associated with experiences of racial discrimination. Varying levels of trauma, PTSD symptoms, and experiences of racial discrimination. Experiences of Discrimination Questionnaire (EOD) (range, 0-9) for count of the number of situations for which each participant reported having unfair treatment for a racial reason. Experiences of trauma and PTSD symptoms were assessed with the Traumatic Events Inventory (TEI) (number of times the person was exposed to trauma; score range, 0-112) and PTSD Symptom Scale (PSS) (score range, 0-51). Response to trauma-relevant vs neutral distractor cues were assessed via functional magnetic resonance imaging during performance of an affective Stroop (attentional control) task. Statistical analyses were conducted at a whole-brain, voxelwise level with familywise error correction. In this study of 55 Black women in the US (mean [SD] age, 37.7 [10.7] years; range, 21-61 years), participants reported a mean (SD) TEI frequency of 33.0 (18.8) and showed moderate levels of current PTSD symptoms (mean [SD] PSS score, 15.4 [12.9]). Mean (SD) EOD scores were 2.35 (2.44) and were moderately correlated with current PTSD symptoms (PSS total: r = 0.36; P=.009) but not with age (r = 0.20; P = .15) or TEI frequency (r = -0.02; P = .89). During attention to trauma-relevant vs neutral images, more experiences of racial discrimination were associated with significantly greater response in nodes of emotion regulation and fear inhibition (ventromedial prefrontal cortex) and visual attention (middle occipital cortex) networks, even after accounting for trauma and severity of PTSD symptoms (brainwide familywise error corrected; r = 0.33 for ventromedial prefrontal cortex; P = .02). Racial discrimination was also associated with affective Stroop task performance; errors on trials with threat-relevant stimuli were negatively correlated with experiences of racial discrimination (r = -0.41; P = .003). These findings suggest that experiences of racial discrimination associate with disproportionately greater response in brain regions associated with emotion regulation and fear inhibition and visual attention. Frequent racism experienced by Black individuals may potentiate attentional and regulatory responses to trauma-relevant stressors and lead to heightened modulation of regulatory resources. This may represent an important neurobiological pathway for race-related health disparities.

Learning biases to angry and happy faces during Pavlovian aversive conditioning.

Learning biases in Pavlovian aversive conditioning have been found in response to specific categories of threat-relevant stimuli, such as snakes or angry faces. This has been suggested to reflect a selective predisposition to preferentially learn to associate stimuli that provided threats to survival across evolution with aversive outcomes. Here, we contrast with this perspective by highlighting that both threatening (angry faces) and rewarding (happy faces) social stimuli can produce learning biases during Pavlovian aversive conditioning. Using a differential aversive conditioning paradigm, the present study (N = 107) showed that the conditioned response to angry and happy faces was more readily acquired and more resistant to extinction than the conditioned response to neutral faces. Strikingly, whereas the effects for angry faces were of moderate size, the conditioned response persistence to happy faces was of relatively small size and influenced by interindividual differences in their affective evaluation, as indexed by a Go/No-Go Association Task. Computational reinforcement learning analyses further suggested that angry faces were associated with a lower inhibitory learning rate than happy faces, thereby inducing a greater decrease in the impact of negative prediction error signals that contributed to weakening extinction learning. Altogether, these findings provide further evidence that the occurrence of learning biases in Pavlovian aversive conditioning is not specific to threat-related stimuli and depends on the stimulus' affective relevance to the organism. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Threat-relevant stimuli cannot be better detected by preschoolers in an inattentional blindness task.

Detecting the unexpected threat-relevant stimuli plays a vital role in preschoolers' daily life safety, but a few studies have investigated how preschoolers process this kind of stimuli. We applied a classical inattentional blindness task (designed by Mack and Rock Inattentional blindness. MIT Press, 1998) to explore whether threat-relevant stimuli could be better detected in an inattentional condition and whether the age and the fluid intelligence could predict the incidence of the detection. With the involvement of two hundred and thirty-nine preschoolers (aged from 4 to 6years), we found that it was not more likely for preschoolers to detect the threat-relevant stimuli (Knife and Snake) compared with the non-threat-relevant stimuli (Spoon and Snail). The age difference of detection only occurred in the divided attentional condition, but not in the inattentional condition. Moreover, the group of 5-year-old preschoolers with higher fluid intelligence scores was more likely to detect the unexpected stimuli, but the prediction was not powerful. These findings demonstrate that the threat-superiority effect on IB does not occur on preschoolers and the individual difference of preschoolers' IB is unstable. This study enriches the cognition of young children's attentional bias to threat-relevant stimuli, and has certain significance to understand the essence of children's attentional process.

Effects of repeated exposure to fearful and disgusting stimuli on fear renewal in blood-injection-injury phobia

Although exposure is effective for blood-injection-injury (BII) phobia, fear often returns after treatment. While disgust has been implicated in BII phobia, its effects on fear renewal are unclear. To address this knowledge gap, the present study examined the effect of repeated video exposure to fearful and disgusting stimuli in multiple contexts on fear renewal in BII phobia. Individuals with BII phobia (N = 57) were randomized to Disgust-Specific Exposure (DSE) which included exposure to disgusting but threat-irrelevant stimuli (i.e., vomit), Fear-Specific Exposure (FSE) which included exposure to threat-relevant stimuli (i.e., injections), or General Negative Exposure (GNE) which included exposure designed to elicit negative affect (i.e., tornado) without being disgusting or threat-relevant. During session one, participants watched a pre- and post-exposure assessment injection video (“pre/post assessment”), and a novel injection video after exposure to assess renewal effects (“novel 1”). Participants came in one week later to rate the same videos, and a new injection video (“novel 2”). For week one outcomes, comparisons of covariate adjusted means indicated the fear-specific group reported significantly lower levels of anxiety than the general-negative group to the post-exposure and novel 1 stimulus. When presented with the post-exposure stimuli during week two, the disgust-specific and fear-specific groups reported significantly lower levels of anxiety than the general negative group. The fear-specific group also reported significantly lower levels of anxiety than the disgust-specific and general-negative groups when presented with novel 1 and novel 2 stimuli at week two. These findings suggest that repeated exposure to threat-relevant cues in multiple contexts does reduce the return of anxiety. However, repeated exposure to disgusting but threat irrelevant stimuli may also produce some therapeutic effects. The implications of the integration of disgust-relevant processes into exposure-based treatment of BII phobia are discussed.

Seeing red? A systematic review of the evidence for attentional biases to threat-relevant stimuli in propensity to reactive aggression

Abstract Psychological models of aggression have suggested that propensity to aggressive behaviour, especially reactive aggression (RA), may be associated with attentional biases to threat or hostile stimuli. Findings to date are inconsistent, but have often treated aggression as a general construct. This review aimed to evaluate the evidence for a specific association of such attentional biases in propensity to RA, excluding populations with known attention processing abnormalities. A systematic search of the literature was undertaken and twelve eligible experiments, reported in nine studies, were identified. Data were combined and reviewed using narrative synthesis, assessing the presence of differences in attentional processing of threat-relevant stimuli in RA, and specificity of biases to threat-related stimuli and to RA. Preliminary and tentative evidence is presented suggesting that such biases are shown by individuals who exhibit high reactive aggression, which may be specific to this form of aggression. Most studies reporting positive findings reported an attentional bias towards interpersonal threat stimuli, with some evidence that this does not generalise to other types of emotional stimuli. However, positive findings were not reported by all studies, and the small number of studies and varied tasks prevented more nuanced analysis. The review also highlights sampling biases which affect generalisability of findings, particularly beyond the male population.

Biased Attention to Threat: Answering Old Questions With Young Infants

For decades, researchers have been interested in humans’ ability to quickly detect threat-relevant stimuli. Here, we review recent findings from infant research on biased attention to threat and discuss how these data speak to classic assumptions about whether attention biases for threat are normative, whether they change with development, and what factors might contribute to this developmental change. We conclude that although there is some stability in attention biases in infancy, various factors—including temperamental negative affect and maternal anxiety—also contribute to shaping the development of biased attention.

Subclinically Anxious Adolescents Do Not Display Attention Biases When Processing Emotional Faces - An Eye-Tracking Study.

Recent research suggests that early difficulties with emotion regulation go along with an increased risk for developing psychiatric disorders, such as anxiety disorders for example. Adolescent anxiety is often referred to as a gateway disorder, due to its high predictability for lifelong persistent mental health problems. It has been shown that clinically anxious adolescents exhibit attention biases toward negative stimuli, yet whether these biases can also be found in the subclinical range of subclinically anxious adolescents is currently unclear. In this study, we set out to investigate this question by combining an emotional Go-Nogo task with eye-tracking techniques to assess attention biases for emotional faces in a subclinical sample of 23 subclinically anxious adolescent girls. This combined approach allowed us to look at both, behavioral and covert attention biases. Using both traditional and Bayesian hypothesis testing, we found no evidence for a bias toward negative, threat-relevant stimuli in the behavioral level or eye-tracking data. We believe that the results can help close a gap in the current literature by showing that like low-anxious adolescents, subclinically anxious adolescents do not exhibit attention biases when viewing de-contextualized emotional stimuli in the Overlap task. Together with previous research findings in clinically anxious participants which have reported high levels of attention biases, our results seem to suggest that attention biases do no increase linearly as a function of individual anxiety level. Future research is now needed to explore the contribution of additional factors, such as depression for example.

Anterior cingulate activation to implicit threat before and after treatment for pediatric anxiety disorders

BackgroundResearch suggests that individuals with anxiety have difficulty ignoring threat distractors when completing tasks with competing stimuli. Studies examining the neural correlates of these emotional processing difficulties in youth anxiety highlight reduced recruitment of regions associated with goal-directed attention, such as the anterior cingulate cortex (ACC). In the current study, we examined neural activation during an emotional conflict task in youth with anxiety disorders before and after treatment. MethodsTwenty-five youth (ages 9–19 years) with generalized, separation, and/or social anxiety disorder and 25 healthy controls underwent 2 functional magnetic resonance imaging scans approximately 13 weeks apart. At each scan, participants completed a task in which they matched shapes in the context of emotional distractors (happy and threatening faces). Between scans, anxious youth were treated with the selective serotonin reuptake inhibitor (SSRI) sertraline or cognitive behavior therapy (CBT). ResultsPrior to treatment, anxious youth exhibited reduced activation of the medial prefrontal cortex, encompassing the rostral ACC, when matching shapes in the context of threat distractors relative to healthy controls. Activation in this region increased in anxious youth after treatment, but remained unchanged in the healthy control group. Increases in rostral ACC activation were related to greater reductions in social anxiety and avoidance symptoms following treatment. ConclusionsEffective treatments for pediatric anxiety may enhance rostral ACC response during attempts to filter out threat-relevant stimuli. Enhanced recruitment of this region may constitute one manner in which CBT and SSRI treatment reduce youth anxiety symptoms, particularly social anxiety and avoidance.

ERP correlates of attentional processing in spider fear: evidence of threat-specific hypervigilance

ABSTRACTAttentional bias towards threat can be demonstrated by enhanced processing of threat-related targets and/or greater interference when threat-related distractors are present. These effects are argued to reflect processing within the orienting and executive control networks of the brain respectively. This study investigated behavioural (RT) and electrophysiological correlates of early selective attention and top-down attentional control among females with high (n = 16) or low (n = 16) spider fear (Mean age = 22 years). Participants completed a novel flanker go/nogo task in which a central schematic flower or spider stimulus was flanked by either congruent or incongruent distractors. Participants responded to green stimuli (go trials) and withheld response to yellow stimuli (nogo trials). High fear participants demonstrated significantly shorter reaction times and greater P1 amplitude to spider targets, suggesting specific hypervigilance towards threat-relevant stimuli. In contrast to predictions, there was little evidence for behavioural interference effects or differences in N2 amplitude when distractor stimuli were threat-relevant.

Rapid detection of snakes modulates spatial orienting in infancy

Recent evidence for an evolved fear module in the brain comes from studies showing that adults, children and infants detect evolutionarily threatening stimuli such as snakes faster than non-threatening ones. A decisive argument for a threat detection system efficient early in life would come from data showing, in young infants, a functional threat-detection mechanism in terms of “what” and “where” visual pathways. The present study used a variant of Posner’s cuing paradigm, adapted to 7–11-month-olds. On each trial, a threat-irrelevant or a threat-relevant cue was presented (a flower or a snake, i.e., “what”). We measured how fast infants detected these cues and the extent to which they further influenced the spatial allocation of attention (“where”). In line with previous findings, we observed that infants oriented faster towards snake than flower cues. Importantly, a facilitation effect was found at the cued location for flowers but not for snakes, suggesting that these latter cues elicit a broadening of attention and arguing in favour of sophisticated “what–where” connections. These results strongly support the claim that humans have an early propensity to detect evolutionarily threat-relevant stimuli.

Threat-induced changes in attention during tests of static and anticipatory postural control

Postural threat, manipulated through changes in surface height, influences postural control. Evidence suggests changes in attention may contribute to this relationship. However, limited research has explored where and how attention is reallocated when threatened. The primary aim of this study was to describe changes in attention when presented with a postural threat, while a secondary aim was to explore associations between changes in attention and postural control. Eighty-two healthy young adults completed tests of static (quiet standing) and anticipatory (rise to toes) postural control under threatening and non-threatening conditions. Participants completed an open-ended questionnaire after each postural task which asked them to list what they thought about or directed their attention toward. Each item listed was assigned a percentage value reflecting how much attention it occupied. Exit interviews were completed to help confirm where attention was directed. Five attention categories were identified: movement processes, threat-relevant stimuli, self-regulatory strategies, task objectives, and task-irrelevant information. For both postural tasks, the percentage values and number of items listed for movement processes, threat-relevant stimuli, and self-regulatory strategies increased under threatening compared to non-threatening conditions, while the percentage values and number of items listed for task objectives and task-irrelevant information decreased. Changes in attention related to movement processes and self-regulatory strategies were associated with changes in static postural control, while changes in attention related to threat-relevant stimuli were associated with changes in anticipatory postural control. These results suggest that threat-induced changes in attention are multidimensional and contribute to changes in postural control.

Pupil Response to Threat in Trauma-Exposed Individuals With or Without PTSD.

An infrequently studied and potentially promising physiological marker for posttraumatic stress disorder (PTSD) is pupil response. This study tested the hypothesis that pupil responses to threat would be significantly larger in trauma-exposed individuals with PTSD compared to those without PTSD. Eye-tracking technology was used to evaluate pupil response to threatening and neutral images. Recruited for participation were 40 trauma-exposed individuals; 40.0% (n = 16) met diagnostic criteria for PTSD. Individuals with PTSD showed significantly more pupil dilation to threat-relevant stimuli compared to the neutral elements (Cohen's d = 0.76), and to trauma-exposed controls (Cohen's d = 0.75). Pupil dilation significantly accounted for 12% of variability in PTSD after time elapsed since most recent trauma, cumulative violence exposure, and trait anxiety were statistically adjusted. The final logistic regression model was associated with 85% of variability in PTSD status and correctly classified 93.8% of individuals with PTSD and 95.8% of those without. Pupil reactivity showed promise as a physiological marker for PTSD.

Autonomic arousal and attentional orienting to visual threat are predicted by awareness.

The rapid detection and evaluation of threat is of fundamental importance for survival. Theories suggest that this evolutionary pressure has driven functional adaptations in a specialized visual pathway that evaluates threat independently of conscious awareness. This is supported by evidence that threat-relevant stimuli rendered invisible by backward masking can induce physiological fear responses and modulate spatial attention. The validity of these findings has since been questioned by research using stringent, objective measures of awareness. Here, we use a modified continuous flash suppression paradigm to ask whether threatening images induce adaptive changes in autonomic arousal, attention, or perception when presented outside of awareness. In trials where stimuli broke suppression to become visible, threatening stimuli induced a significantly larger skin conductance response than nonthreatening stimuli and attracted spatial attention over scrambled images. However, these effects were eliminated in trials where observers were unaware of the stimuli. In addition, concurrent behavioral data provided no evidence that threatening images gained prioritized access to awareness. Taken together, our data suggest that the evaluation and spatial detection of visual threat are predicted by awareness.

Perceptual and conceptual similarities facilitate the generalization of instructed fear

Background and objectivesLearned fear can generalize to neutral events due their perceptual and conceptual similarity with threat relevant stimuli. This study simultaneously examined these forms of generalization to model the expansion of fear in anxiety disorders. MethodsFirst, artificial categories involving sounds, nonsense words and animal-like objects were established. Next, the words from one category were paired with threatening information while the words from the other category were paired with safety information. Lastly, we examined if fear generalized to (i) the conceptually related animal-like objects and (ii) other animal like-objects that were perceptually similar. This was measured using behavioral avoidance, US expectancy ratings and self-reported stimulus valence. ResultsAnimal-like objects conceptually connected to the aversive words evoked heightened fear. Perceptual variants of these animal-like objects also elicit fear. LimitationsFuture research would benefit from the use of online-US expectancy ratings and physiological measures of fear. ConclusionsInvestigating the role of both perceptual and conceptual fear generalization is important to better understand the etiology of anxiety disorders symptoms.

Children’s Attention Detection to Snakes: Evidence from Eye Movements

Previous research shows that preschool children detect snakes quickly than non-threating stimuli(e.g. flowers). In this study, we used eye tracking technology to provide direct evidences about the superior detection about threat-relevant stimuli. Two experiments were designed to testify whether the snakes would be fixated faster and quickly by preschool children and adults. In addition, we also used line drawing snakes and flowers as stimuli to control the shape of snakes and to testify the perceptual template hypothesis. In experiment 1, sixteen 4-to 6-year-old preschool children and 22 undergraduates were recruited as participants. A revised 3 × 3 matrices of color photographs of threat-relevant(snakes) and threat-irrelevant(flowers) stimuli were presented to both preschool children and adults. All participants were asked to find the threat target(snake) among seven non-threat distractors(flowers) and vice versa. Sixteen matrices with 8 pictures(1 target and 7 distractors) were presented to the participants. We changed the standard visual search task that did not present stimuli in the middle of the 3 × 3 matrices to control the central location effect and make the procedure appropriate for eye tracking calibration. It's a 2(age: children, adults)× 2(target: snake, flower) mixed design, and age was the between subject variable. In experiment 2, we improved the stimuli with line drawings to pop out the continuous curvilinear contour of snakes. The design, presentation method was the same as experiment 1. In two experiments, Tobii T120 Eye tracker was used to record the viewing behaviors of adults and children. The results of experiment 1 indicated that both the preschool children and adults fixated snakes faster and with less fixation counts than flowers, and their first fixation duration was shorter on snakes than flowers. Adults performed faster fixation, much less fixation counts than children. As distractors(flower was target), snakes were also fixated quickly than flowers(snake was target). In experiment 2, the same results were found that both children and adults located line drawing snakes quicker than line drawing flowers. And the first fixation duration to snakes were much shorter than flowers. Adults still fixated faster than children. For the snakes as distractors, we found the same results as experiment 1. Compared to the fixations of the line drawing snakes without color and pattern in experiment 2, real and colorful snakes in experiment 1 were fixated faster. The real and colorful snakes were detected faster and with less fixation counts before they were located as distractors. In conclusion, even preschool children who have little snake experience also show faster attention orienting and shorter attention holding. Based on the eye movements evidences, the continuous curvilinear shape plays an important role in the snake relevant threat detection. The eye fixations of line drawing snakes provide direct evidence to the perceptual template theory. To be a special reptile, the color, patterns can boost the quick detection.

Mechanisms of visual threat detection in specific phobia

People with anxiety or stress-related disorders attend differently to threat-relevant compared with non-threat stimuli, yet the temporal mechanisms of differential allocation of attention are not well understood. We investigated two independent mechanisms of temporal processing of visual threat by comparing spider-phobic and non-fearful participants using a rapid serial visual presentation task. Consistent with prior literature, spider phobics, but not non-fearful controls, displayed threat-specific facilitated detection of spider stimuli relative to negative stimuli and neutral stimuli. Further, signal detection analyses revealed that facilitated threat detection in spider-phobic participants was driven by greater sensitivity to threat stimulus features and a trend towards a lower threshold for detecting spider stimuli. However, phobic participants did not display reliably slowed temporal disengagement from threat-relevant stimuli. These findings advance our understanding of threat feature processing that might contribute to the onset and maintenance of symptoms in specific phobia and disorders that involve visual threat information more generally.