Signals for threat modulate attentional capture and holding: Fear-conditioning and extinction during the exogenous cueing task

This experiment investigated whether acquired signals for threat capture and hold visual attention. Cues that were presented in an exogenous attentional cueing task were emotionally modulated using a fear-conditioning paradigm. During acquisition, undergraduate students (55 women, 11 men) learned that one cue (CS+) of the attentional task was a signal for an aversive white noise burst (UCS, 100 dBA) and that another cue (CS?) signalled its nonoccurrence. In a subsequent extinction phase, no UCSs were presented anymore during the cueing task. Results indicated that during acquisition, the CS+ cues strongly captured and held visual attention in comparison with the CS? cues, and that these effects diminished during extinction.     

Hemispheric asymmetry and human associative learning: Interactions with attention

In a previous study (Hugdahl & Brobeck, 1986) it was shown that Pavlovian conditioning to an auditory verbal conditioned stimulus (CS) initially presented only to the left cerebral hemisphere was stronger than when the same CS was presented to the right hemisphere. This was followed up in the present study by controlling for the possibility that the effect was caused by laterally biased attention. The study was performed using the “dichotic extinction paradigm,” which consists of three different phases. During the habituation phase, the CS+ and CS- were presented binaurally and separated in time. During the acquisition phase, the CS+ was followed by a white-noise unconditioned stimulus (UCS). During the dichotic extinction phase, the CS+ and CS- were presented dichotically, i.e., simultaneous presentations on each trial. Half of the subjects had the CS+ in the right ear, and half had the CS+ in the left ear. Each group was further divided into two subgroups, with one subgroup instructed to attend only to the right ear input, and the other subgroup to attend only to the left ear input. During acquisition, larger electrodermal responses were obtained to the CS+ than to the CS-. During dichotic extinction, the CS+ right ear group showed superior resistance to extinction compared to the CS+ left ear group, with no effect of the manipulation of attention. The effect was, however, attenuated when levels of acquisition was used as covariates in an analysis of covariance. There were overall larger responses from the left hand recording.     

Observational fear conditioning in the acquisition and extinction of attentional bias for threat: an experimental evaluation

Anxious persons show automatic and strategic attentional biases for threatening information. Yet, the mechanisms and processes that underlie such biases remain unclear. The central aim of the present study was to elucidate the relation between observational threat learning and the acquisition and extinction of biased threat processing by integrating emotional Stroop color naming tasks within an observational differential fear conditioning procedure. Forty-three healthy female participants underwent several consecutive observational fear conditioning phases. During acquisition, participants watched a confederate displaying mock panic attacks (UCS) paired with a verbal stimulus (CS+), but not with a second nonreinforced verbal stimulus (CS-). As expected, participants showed greater magnitude electrodermal and verbal-evaluative (e.g., distress, fear) conditioned responses to the CS+ over the CS- word. Participants also demonstrated slower color-naming latencies to CS+ compared to the CS- word following acquisition and showed attenuation of this preferential processing bias for threat following extinction. Findings are discussed broadly in the context of the interplay between fear learning and processing biases for threat as observed in persons suffering from anxiety disorders.     

On the costs and benefits of directing attention towards or away from threat-related stimuli: A classical conditioning experiment

In attentional bias modification programs, individuals are trained to attend away from threat in order to reduce emotional reactivity to stressful situations. However, attending towards threat is considered to be a prerequisite for fear reduction in other models of anxiety. We compared both views by manipulating attention towards or away from an acquired signal of threat. The strength of extinction and reacquisition was assessed with threat and US-expectancy ratings. We found more extinction in the attend towards threat group, compared to both the attend away from threat group and a control group in which attention was not manipulated. The results are in line with the Emotional Processing Theory and cognitive accounts of classical conditioning.     

Differential acquisition,extinction, and reinstatement of conditioned suppression in mice

In animals, the reappearance of conditioned fear responses after extinction has been primarily investigated using single-cue conditioning paradigms. However, a differential paradigm can overcome several of the disadvantages associated with a single-cue procedure. In the present study, the reinstatement phenomenon was assessed in mice using a differential conditioned suppression paradigm. In a first phase, one conditioned stimulus (CS + ) was consistently paired with an unconditioned stimulus (US; footshock) while another CS (CS–) was not, resulting in selective suppression of previously trained instrumental behaviour during the CS + . After the extinction phase, half of the animals (reinstatement group) were presented with unsignalled USs, while the other half were not (control group). A differential return of conditioned responding was observed in the reinstatement group, but not in the control group. The implications of these findings for future conditioning research are discussed.     

Differential acquisition, extinction, and reinstatement of conditioned suppression in mice

In animals, the reappearance of conditioned fear responses after extinction has been primarily investigated using single-cue conditioning paradigms. However, a differential paradigm can overcome several of the disadvantages associated with a single-cue procedure. In the present study, the reinstatement phenomenon was assessed in mice using a differential conditioned suppression paradigm. In a first phase, one conditioned stimulus (CS + ) was consistently paired with an unconditioned stimulus (US; footshock) while another CS (CS-) was not, resulting in selective suppression of previously trained instrumental behaviour during the CS + . After the extinction phase, half of the animals (reinstatement group) were presented with unsignalled USs, while the other half were not (control group). A differential return of conditioned responding was observed in the reinstatement group, but not in the control group. The implications of these findings for future conditioning research are discussed.     

Non-differential return of fear in humans after a reinstatement procedure

The present experiment investigated reinstatement of fear in humans using a differential fear conditioning preparation. In this experiment, one neutral stimulus (conditioned stimulus; CS+) was paired with an aversive stimulus (unconditioned stimulus; US) during the acquisition phase, while another neutral stimulus was not (CS−). This procedure led to a difference in responding between the CS+ and the CS− (i.e., differential conditioning). After this acquisition phase, an extinction phase followed, during which both CSs were presented without the US, resulting in a decrease in differential conditioned responding. Reinstatement refers to the return of extinguished conditioned responses due to the experience of US-only trials after the extinction phase. This phenomenon was investigated by presenting half of the participants (reinstatement group) with unpredictable USs after the extinction phase. The control group did not receive these USs after the extinction procedure. The results show that return of fear was clearly apparent after the reinstating USs. This return of fear was, however, not limited to the CS+. An increase in ‘conditioned’ responding was also observed for the control stimulus. This interesting observation will be discussed against the background of a number of recent theoretical conceptualizations of reinstatement.     

Higher attention bias for fear at 8 months of age is associated with better socioemotional competencies during toddlerhood

BackgroundIn previous studies, an attention bias for signals of fear and threat has been related to socioemotional problems, such as anxiety symptoms, and socioemotional competencies, such as altruistic behaviors in children, adolescents and adults. However, previous studies lack evidence about these relations among infants and toddlers.AimsOur aim was to study the association between the individual variance in attention bias for faces and, specifically, fearful faces during infancy and socioemotional problems and competencies during toddlerhood.Study design and subjectsThe study sample was comprised of 245 children (112 girls). We explored attentional face and fear biases at the age of 8 months using eye tracking and the face-distractor paradigm with neutral, happy and fearful faces and a scrambled-face control stimulus. Socioemotional problems and competencies were reported by parents with the Brief Infant and Toddler Social Emotional Assessment (BITSEA) when children were 24 months old.Outcome measures and resultsA higher attentional fear bias at 8 months of age was related to higher levels of socioemotional competence at 24 months of age (β = .18, p = .008), when infants’ sex and temperamental affectivity, maternal age, education and depressive symptoms were controlled. We found no significant association between attentional face or fear bias and socioemotional problems.ConclusionsWe found that the heightened attention bias for fearful faces was related to positive outcomes in early socioemotional development. Longitudinal study designs are needed to explore the changes in the relation between the attention bias for fear or threat and socioemotional development during early childhood.     

Selective attention and avoidance on a pictorial cueing task during stress in clinically anxious and depressed participants

Although it is well established that attentional biases exist in anxious populations, the specific components of visual orienting towards and away from emotional stimuli are not well delineated. The present study was designed to examine these processes. We used a modified spatial cueing task to assess the speed of engagement and disengagement from supraliminal and masked pictorial cues depicting threat, dysphoria, or neutral content in 36 clinically anxious, 41 depressed and 41 control participants. Participants were randomly assigned to a stress or neutral condition. During stress, anxious participants were slow to disengage from masked left hemifield pictures depicting threat or dysphoria, but were quick to disengage from supraliminal threat pictures. Information processing in anxious participants during stress was characterized by early selective attention of emotional stimuli, occurring prior to full conscious awareness, followed by effortful avoidance of threat. Depressed participants were distinct from the anxious group, displaying selective attention for stimuli depicting dysphoria, but not threat, during the neutral condition. In sum, attentional biases in clinical populations are associated with difficulties in the disengagement component of visual orienting. Further, a vigilant-avoidant pattern of attentional bias may represent a strategic attempt to compensate for the early activation of a fear response.     

Plasticity in attention: implications for stress response in children

Attention bias has been suggested as an etiological and maintaining factor in anxiety. However, empirical evidence establishing this causal association is scarce and has been provided only in adults. In this preliminary study, we tested whether an induction of attentional bias can cause changes in vulnerability to stress in children reporting normal anxiety levels. Twenty-six 7-12 year-old children were randomly assigned to two groups. One group was exposed to a training condition designed to induce an attentional bias away from threat. The other group was exposed to a training condition designed to induce an attentional bias toward threat. Children who were trained to attend to threat developed attentional vigilance to threat-related information. The training procedure was ineffective with children who were trained to avoid threat, and their attention remained unbiased. Children from both training groups reported elevated depression scores following stress-induction. However, only the children who were trained to attend to threat subsequently reported elevations in anxiety. The findings suggest that biased attentional responses to threat, among children, can exert a specific influence on the tendency to experience anxiety in the face of stress.     

Effects of endorphin blocking on conditioned SCR in humans

In order to test the hypothesis that low levels of endogenous opioids (endorphins) predispose to strong conditioning effects, female Ss (N = 36) were assigned to a placebo group, a low-dose naltrexone group, or a high-dose naltrexone group and then underwent a classical conditioning procedure. This procedure consisted of an acquisition phase in which all Ss received 5 pairings of a CS+ (neutral picture) and a UCS (100 dB white noise). The CS− (neutral picture) was never followed by a UCS. During extinction, Ss received 4 unreinforced presentations of CS+ and CS−. Throughout the experiment, skin conductance responses (SCRs) to the CSs and UCSs were recorded. Acquisition was successful in that CS+ slides elicited stronger SCRs than CS − slides. However, during acquisition, there was no interaction between drug and differential response (CS+ vs CS−). During extinction, there was no overall remaining effect of conditioning. Again, no evidence was found to suggest that (remaining) effects of conditioning were stronger in the naltrexone treated Ss than in the placebo S's. If anything, the opposite seemed to be true with especially high-dose naltrexone Ss showing relatively weak conditioning effects.     

Frontal and parietal EEG asymmetries interact to predict attentional bias to threat

Frontal and parietal electroencephalographic (EEG) asymmetries mark vulnerability to depression and anxiety. Drawing on cognitive theories of vulnerability, we hypothesise that cortical asymmetries predict attention to threat. Participants completed a dot-probe task in which bilateral face displays were followed by lateralised targets at either short (300 ms) or long (1050 ms) SOA. We also measured N2pc to face onset as an index of early attentional capture. At long SOA only, frontal and parietal asymmetry interacted to predict attentional bias to angry faces. Those with leftward frontal asymmetry showed no attentional bias. Among those with rightward frontal asymmetry those with low right parietal activity showed vigilance for threat, and those with high right parietal activity showed avoidance. Asymmetry was not related to the N2pc or to attentional bias at the short SOA. Findings suggest that trait asymmetries reflect function in a fronto-parietal network that controls attention to threat.     

Early detection and avoidance of threatening faces during passive viewing

To evaluate whether there is an early attentional bias towards negative stimuli, we tracked participants' eyes while they passively viewed displays composed of four Ekman faces. In Experiment 1 each display consisted of three neutral faces and one face depicting fear or happiness. In half of the trials, all faces were inverted. Although the passive viewing task should have been very sensitive to attentional biases, we found no evidence that overt attention was biased towards fearful faces. Instead, people tended to actively avoid looking at the fearful face. This avoidance was evident very early in scene viewing, suggesting that the threat associated with the faces was evaluated rapidly. Experiment 2 replicated this effect and extended it to angry faces. In sum, our data suggest that negative facial expressions are rapidly analysed and influence visual scanning, but, rather than attract attention, such faces are actively avoided.     

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.     

Looking out for danger: An attentional bias towards spatially predictable threatening stimuli

Attentional bias to threat is well established, however, the influence of spatial predictability on this attentional bias has never been investigated. Here we investigated how threat affects attentional capture and disengagement when its spatial location is predictable. Using a visual search paradigm, participants were required to identify a target inside one of a variable number of colored circles. One color (Conditioned Stimulus, CS+) was fear-conditioned using an electrocutaneous stimulus at tolerance level. In the experimental group the CS+ was made spatially predictable (occurred more often at one location in the visual display), while this was not the case in the control group. Results showed no complete automatic capture of attention by the CS+, but the experimental group did show more prioritization of the CS+ and less difficulty to disengage from the CS+ than the control group. Of further importance was the finding that the experimental group also attended to the location that was predictive of the CS+, even when no CS+ was presented. Findings are discussed in terms the effects of predictability on anxiety.     

Attentional bias to threat: Roles of trait anxiety, stressful events, and awareness

Attentional biases for threat stimuli were assessed in high and low trait anxious subjects (n = 66) using a probe detection task. To examine the effects of trait anxiety and situational stressors, each subject was tested three times: Under no stress, laboratory-induced stress, and examination-induced stress. To evaluate the role of awareness, half the word stimuli were presented very briefly (14 msec) and masked, and the other half were presented for 500 msec without a mask. Results showed that high trait anxious subjects under exam stress showed an attentional bias towards unmasked threat stimuli compared with low trait subjects. This effect was not found under lab-induced stress, suggesting that the attentional bias for unmasked threat in high trait subjects may be a function of a prolonged stressor, rather than a transient increase in state anxiety. The results from the masked exposure condition were not predicted; high trait anxious subjects shifted attention towards the spatial location of threat words despite lack of awareness of their lexical content, but this bias was only apparent in the no-stress condition. The results are discussed in relation to recent cognitive theories of anxiety.     

Anxiety and attention to threatening pictures

Previous research using attentional search tasks has revealed an anxiety-related bias favouring attention to threatening words when they are presented simultaneously with emotionally neutral words. In Experiment 1, using a similar task, a related effect was found here with emotionally threatening pictures. When pictures were used as location cues in a second experiment, high-trait anxious individuals were slower than less anxious controls when responding to targets requiring attentional disengagement from threat, and they were slower in general with pictures judged to be highly threatening. In a third experiment using the same task but with a longer cue exposure, a related disengagement difficulty occurred across both groups, although the more general slowing with severe threat was again confined to the anxious group. We conclude that attentional bias involves both a specific difficulty in disengaging attention from the location of any threat and a more general interference effect that is related to threat level.     

The time-course of threat processing in children: a temporal dissociation between selective attention and behavioral interference

Although selective attention to threatening information is an adaptive mechanism, exaggerated attention to threat may be related to anxiety disorders. However, studies examining threat processing in children have obtained mixed findings. In the present study, the time-course of attentional bias for threat and behavioral interference was analyzed in a community sample of 8-18-year-old children (N=33) using a pictorial dot probe task. Threatening and neutral stimuli were shown during 17 ms (masked), 500 ms, and 1250 ms. Results provide preliminary evidence of an automatic attentional bias for threat at 17 ms that persists during later, more controlled stages of information processing (500 and 1250 ms). Furthermore, participants showed a delayed response to threat-containing trials relative to neutral trials in the 500 and 1250 ms condition, which may indicate interference by threat. Together, these results suggest that an attentional bias for threat precedes behavioral interference in children. Furthermore, results indicate that performance in daily life can be temporarily interrupted by the processing of threatening information. In addition, results of earlier studies into selective attention in children using tasks based on behavioral responses may have been confounded by interference effects of threat. For future studies, we recommend to take behavioral interference into account.     

Attentional bias during emotional processing: evidence from an emotional flanker task using IAPS

Attention is biased towards threat-related stimuli. In three experiments, we investigated the mechanisms, processes, and time course of this processing bias. An emotional flanker task simultaneously presented affective or neutral pictures from the international affective picture system database either as central response-relevant stimuli or surrounding response-uninformative flankers. Participants’ response times to central stimuli was measured. The attentional bias was observed when stimuli were presented either for 1500?ms (Experiment 1) or 500?ms (Experiment 2). The threat-related attentional bias held regardless of the stimuli competing for attention even when presentation time was further reduced to 200?ms (Experiment 3). The results indicate that automatic and controlled mechanisms may interact to modulate the orientation of attention to threat. The data presented here shed new light on the mechanisms, processes, and time course of this long investigated by still largely unknown processing bias.     

Efficacy of Attention Bias Modification Using Threat and Appetitive Stimuli: A Meta-Analytic Review

Attention bias modification (ABM) protocols aim to modify attentional biases underlying many forms of pathology. Our objective was to conduct an effect size analysis of ABM across a wide range of samples and psychological problems. We conducted a literature search using PubMed, PsycInfo, and author searches to identify randomized studies that examined the effects of ABM on attention and subjective experiences. We identified 37 studies (41 experiments) totaling 2,135 participants who were randomized to training toward neutral, positive, threat, or appetitive stimuli or to a control condition. The effect size estimate for changes in attentional bias was large for the neutral versus threat comparisons (g = 1.06), neutral versus appetitive (g = 1.41), and neutral versus control comparisons (g = 0.80), and small for positive versus control (g = 0.24). The effects of ABM on attention bias were moderated by stimulus type (words vs. pictures) and sample characteristics (healthy vs. high symptomatology). Effect sizes of ABM on subjective experiences ranged from 0.03 to 0.60 for postchallenge outcomes, –0.31 to 0.51 for posttreatment, and were moderated by number of training sessions, stimulus type, and stimulus orientation (top/bottom vs. left/right). Fail-safe N calculations suggested that the effect size estimates were robust for the training effects on attentional biases, but not for the effect on subjective experiences. ABM studies using threat stimuli produced significant effects on attention bias across comparison conditions, whereas appetitive stimuli produced changes in attention only when comparing appetitive versus neutral conditions. ABM has a moderate and robust effect on attention bias when using threat stimuli. Further studies are needed to determine whether these effects are also robust when using appetitive stimuli and for affecting subjective experiences.