Attention training and the threat bias: an ERP study

Anxiety is characterized by exaggerated attention to threat. Several studies suggest that this threat bias plays a causal role in the development and maintenance of anxiety disorders. Furthermore, although the threat bias can be reduced in anxious individuals and induced in non-anxious individual, the attentional mechanisms underlying these changes remain unclear. To address this issue, 49 non-anxious adults were randomly assigned to either attentional training toward or training away from threat using a modified version of the dot probe task. Behavioral measures of attentional biases were also generated pre- and post-training using the dot probe task. Event-related potentials (ERPs) were generated to threat and non-threat face pairs and probes during pre- and post-training assessments. Effects of training on behavioral measures of the threat bias were significant, but only for those participants showing pre-training biases. Attention training also influenced early spatial attention, as measured by post-training P1 amplitudes to cues. Results illustrate the importance of taking pre-training attention biases in non-anxious individuals into account when evaluating the effects of attention training and tracking physiological changes in attention following training.     

Threat-based cognitive biases in anxious children: comparison with non-anxious children before and after cognitive behavioural treatment

Attention and interpretation biases for threat stimuli were assessed in 19 anxious (ANX) children before and after cognitive behavioural therapy (CBT), and compared with responses from 19 non-anxious (NA) control children collected over the same period. Attentional bias was assessed using a picture version of the visual probe task with threat, neutral and pleasant pictures. Threat interpretation bias was assessed using both a homographs task in which children used homograph words in a sentence and their neutral or threatening meaning was assessed, and a stories task in which children rated their negative emotion, danger judgments, and influencing ability in ambiguous situations. ANX children showed attention biases towards threat on the visual probe task and threat interpretation biases on the stories task but not the homographs task at pre-treatment in comparison with NA children. Following treatment, ANX children's threat interpretation biases as assessed on the stories task reduced significantly to within levels comparable to NA children. However, ANX children continued to show larger attentional biases towards threat than pleasant pictures on the visual probe task at post-treatment, whereas NA children did not show attentional biases. Moreover, a residual threat interpretation style on the stories task at post-treatment was associated with higher anxiety symptoms in both ANX and NA children.     

Interpretation biases in angry and anxious individuals

Although previous research has demonstrated many similarities between anxious and angry individuals, few studies have compared the degree and direction to which they exhibit cognitive biases in the presence of threat. The present study was a preliminary investigation of 28 angry participants, 30 anxious participants, and 26 non-angry/non-anxious participants who rated the likelihood of various explanations to account for ambiguous but potentially threatening events described in short prose passages. Angry participants rated the likelihood of positive explanations for ambiguous events lower than non-angry/non-anxious participants. Angry participants rated the likelihood of anger-related explanations higher than anxious and non-angry/non-anxious participants, and both angry and anxious participants rated anxiety-related explanations as being more likely than non-angry/non-anxious participants. Thus, both angry and anxious participants demonstrated a negative interpretation bias, although the bias was more pervasive in angry participants.     

Vigilance for threat: effects of anxiety and defensiveness

Eysenck’s (1997) theory that attentional biases for threat vary as an interactive function of trait anxiety and defensiveness was tested using a visual probe task. Two stimulus exposure conditions were used to explore a secondary issue concerning attentional allocation over time. Results indicated that, among high trait anxious participants, only those with low levels of defensiveness showed vigilance for threatening faces presented for 500 ms. They also showed an attentional preference for neutral faces, relative to happy faces, irrespective of exposure condition. This pattern was reversed in high trait anxious participants with high levels of defensiveness, who showed an attentional bias towards happy faces (relative to neutral faces) under both exposure conditions. The findings are discussed in relation to their implications for (a) the significance of measures of defensiveness for the conceptualization of high trait anxious individuals, and (b) the status of anxiety-related biases at different stages of information processing.     

Effects of stress and anxiety on the processing of threat stimuli

Two experiments extended the work of MacLeod and Mathews (1988) and examined whether a cognitive bias for threat information is a function of state or trait anxiety. Color-naming and attention deployment tasks were used to assess the effects of a stress manipulation procedure on attentional responses in high and low trait anxious subjects. Subjects under high stress selectively allocated processing resources toward threat stimuli, irrespective of their trait anxiety level. There was no consistent evidence of a cognitive bias associated with trait anxiety, and the effect of the stress manipulation did not appear to be mediated by state anxiety. It was suggested that trait factors do not modify attentional biases associated with acute stress, but may influence such biases when stress is prolonged.     

Attentional bias in high- and low-anxious individuals: evidence for threat-induced effects on engagement and disengagement

Attentional bias to threatening visual stimuli (words or pictures) is commonly present in anxious individuals, but not in non-anxious people. There is evidence to show that attentional bias to threat can be induced in all individuals when threat is imposed by threat not of symbolic nature, but by cues that predict aversive stimulation (loud noise or electric shock). However, it is not known whether attentional bias in such situations is still influenced by individual differences in anxiety. This question was addressed in two experiments using a spatial cuing task in which visual cues predicted the occurrence of an aversive event consisting of a loud human scream. Speeded attentional engagement to threat cues was positively correlated with trait anxiety in Experiment 1. Experiment 2 showed that speeded attentional engagement was present only in participants selected for high anxiety but not in low-anxious participants. In both experiments, slower disengagement from threat cues was found in all participants, irrespective of their trait anxiety levels.     

Attentional bias in high- and low-anxious individuals: Evidence for threat-induced effects on engagement and disengagement

Attentional bias to threatening visual stimuli (words or pictures) is commonly present in anxious individuals, but not in non-anxious people. There is evidence to show that attentional bias to threat can be induced in all individuals when threat is imposed by threat not of symbolic nature, but by cues that predict aversive stimulation (loud noise or electric shock). However, it is not known whether attentional bias in such situations is still influenced by individual differences in anxiety. This question was addressed in two experiments using a spatial cuing task in which visual cues predicted the occurrence of an aversive event consisting of a loud human scream. Speeded attentional engagement to threat cues was positively correlated with trait anxiety in Experiment 1. Experiment 2 showed that speeded attentional engagement was present only in participants selected for high anxiety but not in low-anxious participants. In both experiments, slower disengagement from threat cues was found in all participants, irrespective of their trait anxiety levels.     

Fear of negative evaluation and attentional bias for facial expressions: An event-related study

Numerous studies have shown an exacerbation of attentional bias towards threat in anxiety states. However, the cognitive mechanisms responsible for these attentional biases remain largely unknown. Further, the authors outline the need to consider the nature of the attentional processes in operation (hypervigilance, avoidance, or disengagement). We adapted a dot-probe paradigm to record behavioral and electrophysiological responses in 26 participants reporting high or low fear of evaluation, a major component of social anxiety. Pairs of faces including a neutral and an emotional face (displaying anger, fear, disgust, or happiness) were presented during 200 ms and then replaced by a neutral target to discriminate. Results show that anxious participants were characterized by an increased P1 in response to pairs of faces, irrespective of the emotional expression included in the pair. They also showed an increased P2 in response to angry–neutral pairs selectively. Finally, in anxious participants, the P1 response to targets was enhanced when replacing emotional faces, whereas non-anxious subjects showed no difference between the two conditions. These results indicate an early hypervigilance to face stimuli in social anxiety, coupled with difficulty in disengaging from threat and sustained attention to emotional stimuli. They are discussed within the framework of current models of anxiety and psychopathology.     

Processing efficiency in anxiety: Evidence from eye-movements during visual search

It is generally held that anxiety is characterized by an attentional bias for threatening information. In recent years there has been an important debate whether these biases reside at the level of attentional selection (threat detection) or attentional processing after threat detection (attentional disengagement). In a visual search task containing emotional facial expressions, eye-movements were examined before and after threat detection in high and low trait anxious individuals to further elucidate the temporal unfolding of attentional bias. Results indicated that high-anxious individuals neither showed facilitated orienting to threat nor impaired disengagement of visual attention from threat. Interestingly, the presence of threat in the visual search display was associated with increased decision times in high-anxious individuals. These results challenge some of the current views on attentional bias to threat but indicate that emotional information reduces processing efficiency in anxiety.     

Anxiety, conscious awareness and change detection

Attentional scanning was studied in anxious and non-anxious participants, using a modified change detection paradigm. Participants detected changes in pairs of emotional scenes separated by two task irrelevant slides, which contained an emotionally valenced scene (the 'distractor scene') and a visual mask. In agreement with attentional control theory, change detection latencies were slower overall for anxious participants. Change detection in anxious, but not non-anxious, participants was influenced by the emotional valence and exposure duration of distractor scenes. When negative distractor scenes were presented at subliminal exposure durations, anxious participants detected changes more rapidly than when supraliminal negative scenes or subliminal positive scenes were presented. We propose that for anxious participants, subliminal presentation of emotionally negative distractor scenes stimulated attention into a dynamic state in the absence of attentional engagement. Presentation of the same scenes at longer exposure times was accompanied by conscious awareness, attentional engagement, and slower change detection.     

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.     

Intergenerational transmission of attentional bias and anxiety

Earlier evidence has revealed a bi‐directional causal relationship between anxiety and attention biases in adults and children. This study investigated the prospective and concurrent relations between anxiety and attentional bias in a sample of 89 families (mothers, fathers, and first‐born children). Parents’ and children's attentional bias was measured when children were 7.5 years old, using both a visual probe task and visual search task with angry versus happy facial expressions. Generalized and social anxiety symptoms in parents and children were measured when children were 4.5 and 7.5 years old. Anxiety in parents and children was prospectively (but not concurrently) related to their respective attentional biases to threat: All participants showed a larger attentional bias to threat in the visual search (but not in the visual probe) task if they were more anxious at the 4.5 (but not at the 7.5) year measurement. Moreover, parents’ anxiety levels were prospectively predictive of the visual search attentional bias of their children after controlling for child anxiety. More anxiety in mothers at 4.5 years was related to a faster detection of angry among happy faces, while more anxiety in fathers predicted a faster detection of happy among angry faces in children at 7.5 years. We found no direct association between parental and child attentional biases. Our study contributes to the recently emerging literature on attentional biases as a potential mechanism in the intergenerational transmission of anxiety by showing that parents’ anxiety rather than parents’ attentional bias contributes to the intergenerational transmission of risk for child anxiety.     

Health anxiety, anxiety sensitivity, and attentional biases for pictorial and linguistic health-threat cues

The study investigated attentional biases for pictorial and linguistic health-threat stimuli in high and low health anxious individuals, who were selected from the upper and lower quartile ranges of a normal sample using a screening measure of health anxiety. Attentional bias was assessed using a visual probe task which presented health-threat and neutral pictures and words at two exposure durations, 500 ms and 1250 ms. The prediction that the high health anxious group would show a greater attentional bias for health-threat cues than the low health anxious group was not supported despite the groups being well-differentiated on a general measure of health anxiety, the Illness Attitudes Scale (IAS). Instead, the results indicated that individuals with high levels of anxiety sensitivity showed a significantly greater initial attentional bias for threat pictures compared with those with low anxiety sensitivity, as assessed by the Anxiety Sensitivity Index (ASI).     

Health anxiety,anxiety sensitivity,and attentional biases for pictorial and linguistic health‐threat cues

The study investigated attentional biases for pictorial and linguistic health‐threat stimuli in high and low health anxious individuals, who were selected from the upper and lower quartile ranges of a normal sample using a screening measure of health anxiety. Attentional bias was assessed using a visual probe task which presented health‐threat and neutral pictures and words at two exposure durations, 500 ms and 1250 ms. The prediction that the high health anxious group would show a greater attentional bias for health‐threat cues than the low health anxious group was not supported despite the groups being well‐differentiated on a general measure of health anxiety, the Illness Attitudes Scale (IAS). Instead, the results indicated that individuals with high levels of anxiety sensitivity showed a significantly greater initial attentional bias for threat pictures compared with those with low anxiety sensitivity, as assessed by the Anxiety Sensitivity Index (ASI).     

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.     

Autobiographical memory in angry and anxious individuals

Recent studies have found that angry individuals are characterized by more pronounced attentional and interpretation biases toward threat than anxious individuals. The present study examined anger-related, anxiety-related, and neutral autobiographical memories in 35 angry participants, 33 anxious participants, and 29 non-angry/non-anxious, or healthy participants. Objective indices of autobiographical memories (i.e., retrieval latency, coding of specificity and affective tone) suggested that groups retrieved memories with similar properties. However, both angry and anxious participants rated their memories as less pleasant than healthy participants. These results indicate that memory biases are not part of the cognitive sequelae associated with anger and anxiety, although aspects of the appraisal of these personal memories are distorted.     

Emotional context influences access of visual stimuli to anxious individuals' awareness

Anxiety has been associated with enhanced unconscious processing of threat and attentional biases towards threat. Here, we focused on the phenomenology of perception in anxiety and examined whether threat-related material more readily enters anxious than non-anxious individuals' awareness. In six experiments, we compared the stimulus exposures required for each anxiety group to become objectively or subjectively aware of masked facial stimuli varying in emotional expression. Crucially, target emotion was task irrelevant. We found that high trait-anxiety individuals required less sensory evidence (shorter stimulus exposure times) to become aware of the face targets. This anxiety-based difference was observed for fearful faces in all experiments, but with non-threat faces, it emerged only when these were presented among threatening faces. Our findings suggest a prominent role for affective context in high-anxiety individuals' conscious perception of visual stimuli. Possible mechanisms underlying the influence of context in lowering awareness thresholds in anxious individuals are discussed.     

Threat interpretation bias as a vulnerability factor in childhood anxiety disorders

The present study examined threat interpretation biases in children 7-12 years of age with separation, social and generalised anxiety disorders (N=15), non-anxious offspring at risk due to parental anxiety (N=16) and non-anxious controls of non-anxious parents (N=14). Children provided interpretations of ambiguous situations to assess cognitive, emotional and behavioural responses. In comparison with non-anxious control children and at-risk children who did not differ from each other, anxious children reported stronger negative emotion and less ability to influence ambiguous situations. These results suggest that threat interpretation bias may be a cognitive factor associated with ongoing childhood anxiety but not a vulnerability factor associated with parental anxiety.     

Does anxiety lead to selective processing of threat-related information?

Four experiments investigating the detailed nature of the attentional bias in anxiety are reported. Previous research using the Stroop task has shown that, when compared with non-patient controls, anxious patients are relatively slower at colour naming threat-related words than non-threat words. Experiments One and Two investigated whether this apparent attentional bias is a function of anxiety per se and/or is related to patient/non-patient status. Experiment One compared colour-naming times for threat and non-threat words in low, medium and high trait anxiety normal subjects. High anxiety was not associated with slower colour-naming times for threat words. Experiment Two compared generalized anxiety disorder patients with equally anxious non-patients and found that the patients were significantly slower at colour-naming threat words. Read aloud and dwell tasks were also included in these experiments in order to identify the mechanism of Stroop interference. Experiments Three and Four investigated whether anxious patients' attentional bias is specific to threat-related material or also extends to certain positive, emotional material. In Experiment Three words used in previous Stroop studies were rated for emotionality. Threat words were more emotional, as well as more threatening, than control words, indicating that previous studies have confounded threat and emotionality. Experiment Four compared colour-naming times for threat words, equally emotional positive words, and neutral words. Consistent with the emotionality hypothesis, generalized anxiety disorder patients were slower than non-anxious controls at colour naming both threat words and positive words. The theoretical, methodological and clinical implications of these results are discussed.     

Anxiety-related attentional biases and their regulation by attentional control

This study examined the role of self-reported attentional control in regulating attentional biases related to trait anxiety. Simple detection targets were preceded by cues labeling potential target locations as threatening (likely to result in negative feedback) or safe (likely to result in positive feedback). Trait anxious participants showed an early attentional bias favoring the threatening location 250 ms after the cue and a late bias favoring the safe location 500 ms after the cue. The anxiety-related threat bias was moderated by attentional control at the 500-ms delay: Anxious participants with poor attentional control still showed the threat bias, whereas those with good control were better able to shift from the threatening location. Thus, skilled control of voluntary attention may allow anxious persons to limit the impact of threatening information.