Selective attention for masked and unmasked emotionally toned stimuli: Effects of trait anxiety,state anxiety,and test order

We investigated selective attention for masked and unmasked, threat, and positively valenced words, in high trait anxious (HTA) and low trait anxious (LTA) individuals using the emotional Stroop colour‐naming task. State anxiety was varied within participants through the threat of electric shock. To investigate whether the sequencing of the state anxiety manipulation affected colour‐naming latencies, the ordering of the shock threat and shock safe conditions was counterbalanced across participants. The results indicated that the ordering of the state anxiety manipulation moderated masked and unmasked threat bias effects. Specifically, relative to LTA individuals, HTA individuals showed a threat interference effect, but this effect was limited to those who performed under the threat of shock in the later stages of the experiment. Irrespective of exposure mode and state anxiety status, all individuals showed interference for threat in the early stages of the experiment, relative to a threat facilitation effect in the later stages of the experiment. For the unmasked trials alone, the data also revealed a significant threat interference effect for the HTA group relative to the LTA group in the shock threat condition, and this effect was evident irrespective of shock threat order. The results are discussed with respect to the automatic nature of emotional processing in anxiety.     

The effect of induced anxiety on cognition: threat of shock enhances aversive processing in healthy individuals

Individuals with anxiety disorders demonstrate altered cognitive performance including (1) cognitive biases towards negative stimuli (affective biases) and (2) increased cognitive rigidity (e.g., impaired conflict adaptation) on affective Stroop tasks. Threat of electric shock is frequently used to induce anxiety in healthy individuals, but the extent to which this manipulation mimics the cognitive impairment seen in anxiety disorders is unclear. In this study, 31 healthy individuals completed an affective Stroop task under safe and threat-of-shock conditions. We showed that threat (1) enhanced aversive processing and abolished a positive affective bias but (2) had no effect on conflict adaptation. Threat of shock thus partially models the effects of anxiety disorders on affective Stroop tasks. We suggest that the affective state of anxiety—which is common to both threat and anxiety disorders—modulates the neural inhibition of subcortical aversive processing, whilst pathologies unique to anxiety disorders modulate conflict adaptation.     

The role of anxiety and perspective-taking strategy on affective empathic responses

Empathy is an important pro-social behaviour critical to a positive client–therapist relationship. Therapist anxiety has been linked to reduced ability to empathise and lower client satisfaction with therapy. However, the nature of the relationship between anxiety and empathy is currently unclear. The current study investigated the effect of experimentally-induced anxiety on empathic responses elicited during three different perspective-taking tasks. Perspective-taking was manipulated within-subjects with all participants (N = 52) completing imagine-self, imagine-other and objective conditions. A threat of shock manipulation was used to vary anxiety between-subjects. Participants in the threat of shock condition reported higher levels of anxiety during the experiment and lower levels of empathy-related distress for the targets than participants in the control condition. Perspective-taking was associated with higher levels of empathy-related distress and concern compared to the objective condition. The present results suggest that perspective-taking can to a large extent mitigate the influence of heightened anxiety on an individual’s ability to empathise.     

Effects of Threat on Police Officers' Shooting Behavior: Anxiety,Action Specificity,and Affective Influences on Perception

In the current study, we investigated the impact of threat and response mode on police officers' distance perception and shooting behavior in relation to a suspect that approached with a knife. To manipulate threat and increase anxiety, the suspect carried either a plastic knife (low threat) or an electrical knife (high threat). Regarding the manipulation of response mode, officers provided either an actual shooting response or indicated their shot verbally. In both cases, perceptual judgments of shooting distances were assessed through visual matching. Results show that high threat led to earlier shooting, but only for actual shooting responses. Although high threat generally induced more anxiety, perceptual judgments remained unaffected by threat and indicated systematic underestimations of the distance to the suspect. It is suggested that in the online control of action, increased anxiety does not affect distance perception but alters the functional relationship between distance and perceived threat, thereby causing officers to shoot the approaching suspect at an earlier stage. Copyright © 2012 John Wiley & Sons, Ltd.     

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.     

Anticipation of interoceptive threat in highly anxiety sensitive persons

Anticipatory anxiety plays a major role in the etiology of panic disorder. Although anticipatory anxiety elicited by expectation of interoceptive cues is specifically relevant for panic patients, it has rarely been studied. Using a population analogue in high fear of such interoceptive arousal sensations (highly anxiety sensitive persons) we evaluated a new experimental paradigm to assess anticipatory anxiety during anticipation of interoceptive (somatic sensations evoked by hyperventilation) and exteroceptive (electric shock) threat. Symptom reports, autonomic arousal, and defensive response mobilization (startle eyeblink response) were monitored during threat and matched safe conditions in 26 highly anxiety sensitive persons and 22 controls. The anticipation of exteroceptive threat led to a defensive and autonomic mobilization as indexed by a potentiation of the startle response and an increase in skin conductance level in both experimental groups. During interoceptive threat, however, only highly anxiety sensitive persons but not the controls exhibited a startle response potentiation as well as autonomic activation. The anticipation of a hyperventilation procedure thus seems a valid paradigm to investigate anticipatory anxiety elicited by interoceptive cues in the clinical context.     

Selective processing of masked and unmasked verbal threat material in anxiety: Influence of an immediate acute stressor

Attentional biases for threat were investigated using a computerised version of the emotional Stroop task. The study examined the influence of state and trait anxiety by employing a student sample assigned to high trait anxious (HTA; n=32) or low trait anxious (LTA; n=32) groups on the basis of questionnaire scores, and state anxiety was manipulated within participants through the threat of electric shock. Threatening words that were either unrelated (e.g., cancer, danger) or related to the threat of shock (e.g., electrocute, shock) were presented to participants both within and outside of awareness. In the latter condition a backward masking procedure was used to prevent awareness and exposure thresholds between the target and mask were individually set for each participant. For unmasked trials the HTA group showed significant interference in colour naming for all threat words relative to control words when performing under the threat of shock, but not in the shock safe condition. For the masked trials, despite chance performance in being able to identify the lexical status of the items, HTA participants showed facilitated colour naming for all threat words relative to control items when performing under threat of shock, but this effect was not evident in the shock safe condition. Neither valence of the items nor the threat of shock influenced colour naming latencies in either exposure mode for the LTA group.     

The effect of trait anxiety and mood manipulation on the breadth of attention

Eysenck (1992) predicts that among trait‐anxious individuals high levels of state anxiety broaden the attentional beam in order to facilitate the detection of threat. An experiment was therefore conducted to investigate the interactive role of trait anxiety and mood manipulation on attentional broadening. Target material varying in threat‐relatedness and concern‐relevance was presented to participants' central (parafoveal) and peripheral visual field. Whilst a mood manipulation was associated with a broadening of the attentional beam, it occurred irrespective of trait anxiety. However, differences in the processing of target material were determined by an interaction between trait anxiety and the mood manipulation. Specifically, when placed in an anxiety‐provoking mood manipulation, those high in anxiety increased in their vigilance for concern‐relevant threatening material. These results are discussed in light of Eysenck's hypervigilance theory of anxiety and attention. Copyright © 1999 John Wiley & Sons, Ltd.     

Anxiety and the spelling and use in sentences of threat/neutral homophones

The disambiguation of threat/neutral homophones was investigated in high- and low-trait anxiety subjects who had been exposed to either a positive or a negative mood manipulation procedure. Subjects were required first to spell each auditorily presented word and second, to generate and speak a sentence using the word. Difference indices were calculated for the spelling and the sentence usage data, i.e. the number of threat minus neutral interpretations. Examination of these indices revealed that subjects exposed to the negative mood manipulation procedure produced relatively more threat than neutral interpretations (for both spelling and sentence usage) than did subjects exposed to the positive mood manipulation procedure. Multiple regression analyses revealed that both the trait anxiety and mood manipulation variables contributed significantly to the prediction of the difference index on the spelling task. In the analysis of the use of homophones in sentences, only the mood manipulation variable contributed significantly to the prediction of the difference index on the sentence usage task.     

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.     

Influence of denial (situation redefinition) and projection on anxiety associated with threat to self-esteem.

Subjects in a threat condition were informed that they had failed an important test while subjects in a nonthreat condition were not told that they had failed. To manipulate the use and timing of coping strategies for dealing with threat, subjects were told to (a) redefine the nature and importance of the test before receiving feedback, (b) redefine the nature and importance of the test after feedback, or (c) estimate the performance of their friends on the test (i.e., project) after receiving feedback. Repeated measures of subjective anxiety and pulse rate indicated that (a) the threat manipulation was effective in increasing stress, (b) redefinition occurring before the onset of threat was effective in eliminating stress, and (c) redefinition occuring after the onset of threat was ineffective in reducing stress. Projection reduced the report of subjective anxiety. The results revealed factors that influence coping strategy effectiveness and resolved conflicts in previous findings.     

Selective attention for masked and unmasked threatening words in anxiety: Effects of trait anxiety, state anxiety and awareness

We investigated the effects of awareness on selective attention for masked and unmasked verbal threat material using a computerised version of the emotional Stroop. Participants were assigned to the high trait anxious (HTA) and low trait anxious (LTA) groups on the basis of questionnaire scores, and state anxiety was manipulated within participants through the threat of electric shock. To investigate the effects of awareness on responses to threat, the mode of exposure was blocked such that half the participants received masked trials before the unmasked trials, whereas the other half received the reverse order. The results revealed that there was no difference between the HTA and LTA groups in responses to threat for those who received the masked trials before the unmasked trials. However, when unmasked trials were presented before the masked trials HTA individuals were significantly slower to respond to both masked and unmasked threat words compared to the LTA group, and these effects were not further modified by participants' state anxiety status. The results are discussed in terms of the automatic nature of threat processing in anxiety.     

Safety behaviours preserve threat beliefs: Protection from extinction of human fear conditioning by an avoidance response

A laboratory autonomic conditioning procedure was used to establish fear conditioning in human participants by pairing neutral stimuli with electric shock. Participants were also trained to make a button-press response to avoid shock. A target fear stimulus was then extinguished by presenting it without shock. The experimental group was given the opportunity to make the avoidance response during extinction whereas the control group was not. When the fear stimulus was tested without the response available, the control group showed normal extinction of both shock expectancy ratings and skin conductance responses, but the experimental group showed “protection from extinction”: they continued to give high expectancy ratings and strong skin conductance responses. We interpret this effect as analogous to the role of within-situation safety behaviours in preserving threat beliefs during exposure therapy for anxiety disorders. The results support a cognitive account of learning and anxiety. The procedure provides a potential laboratory model for further examination of the cognitive and neural mechanisms underlying anxiety and its reduction.     

Human anterior and posterior hippocampus respond distinctly to state and trait anxiety

We examined whether anterior and posterior hippocampal subregions in humans show distinct relationships to state and trait anxiety. In rodents, the ventral (but not dorsal) hippocampus is critically involved in contextual anxiety, whereas dorsal hippocampus is affected by chronic stress and genetically bred trait anxiety. These studies suggest that state forms of anxiety may be more associated with anterior (ventral in rodents) hippocampus, whereas trait forms of anxiety maybe more associated with posterior (dorsal in rodents) hippocampus. Participants were placed under alternating blocks of threat of shock and safety conditions while performing a secondary task, and state and trait anxiety measures were obtained. Using subject-specific anatomically defined masks, we found that state anxiety was related to activity in anterior but not posterior hippocampus, whereas trait anxiety showed the opposite pattern. Additionally, a psychophysiological connectivity analysis showed that activity in anterior hippocampus was more strongly related to activity in ventromedial prefrontal cortex under threat than under safety conditions, significantly more so than activity in posterior hippocampus was. Hence, anterior hippocampus shows a distinct moment-to-moment connectivity profile with other neural regions during threat relative to posterior hippocampus. The findings provide several lines of evidence for functional differentiation of anterior and posterior hippocampal involvement across state and trait components of anxiety in humans.     

The effects of safety behaviors on the fear of contamination: an experimental investigation

The strategies used by anxious individuals to prevent feared outcomes, known as safety behaviors, are thought to maintain pathological anxiety by preventing the disconfirmation of inaccurate threat beliefs. However, it is possible that safety behaviors might also contribute to the development and exacerbation of anxiety symptoms. The present study tested this notion in a sample of undergraduate participants with either low (n=30) or high (n=26) levels of contamination fear. After a week-long baseline period, participants spent 1 week engaging in a clinically representative array of contamination-related safety behaviors on a daily basis, followed by a second baseline period. Subsequent to the safety behavior manipulation, participants evidenced statistically significant increases in threat overestimation, contamination fear symptoms, and emotional and avoidant responses to three contamination-related behavioral avoidance tasks (BATs). In contrast, anxiety and depressive symptoms remained stable. The magnitude of change in contamination concerns was equivalent among participants in both contamination fear groups. Our findings suggest that contamination-related safety behaviors elicit a modest and specific increase in the fear of contamination. Possible mechanisms for this effect, as well as implications for the role of safety behaviors in the psychopathology of anxiety disorders, are discussed.     

A multicomponent investigation of the interaction of generalized anxiety and phobia

Forty female undergraduates forming four groups, high or low trait anxiety with or without a specific fear (rats), participated in a psychophysiological assessment of their response to the phobic object, a neutral object (rabbit), and to a general anxiety-induction procedure (threat of shock). Subjects also completed a number of tasks requiring sustained attention. Blood samples were drawn to determine thyroid hormone (T3 and T4) levels. Trait anxiety was found to interact with specific fear in response to the feared object. The high-trait anxious/high-fear group was most physiologically responsive to the rat. Trait- anxious subjects were more responsive to the threat of shock and showed performance deficits on reaction time, vigilance, and backward digit span tasks. These subjects also had significantly higher T3 and T4 levels. The findings are discussed with regard to the role of general anxiety in the etiology and/or maintenance of specific fears and the role of thyroid hormones in accentuating physiological response to feared stimuli.     

Effect of anxiety on behavioural pattern separation in humans

Behavioural pattern separation (BPS), the ability to distinguish among similar stimuli based on subtle physical differences, has been used to study the mechanism underlying stimulus generalisation. Fear overgeneralisation is often observed in individuals with posttraumatic stress disorder and other anxiety disorders. However, the relationship between anxiety and BPS remains unclear. The purpose of this study was to determine the effect of anxiety (threat of shock) on BPS, which was assessed across separate encoding and retrieval sessions. Images were encoded/retrieved during blocks of threat or safety in a 2?×?2 factorial design. During retrieval, participants indicated whether images were new, old, or altered. Better accuracy was observed for altered images encoded during periods of threat compared to safety, but only if those images were also retrieved during periods of safety. These results suggest that overgeneralisation in anxiety may be due to altered pattern separation.     

The role of information in attenuating behavioral responses to stress: a reinterpretation of the misattribution phenomenon.

Two experiments replicating and extending Ross, Rodin, and Zimbardo were conducted to determine whether reductions in emotional behavior resulted from misattribution of naturally occurring arousal states or from informational factors confounded in previous research. In Experiment 1, arousal or arousal-irrelevant symptoms were attributed to noise or the threat of shock. Subjects receiving arousal symptoms avoided shock less, regardless of attribution. Extended manipulation checks revealed no evidence of differential attribution of arousal. In Experiment 2 subjects heard high or low noise. Arousal symptoms were attributed to noise or threat of shock. Subjects for whom arousal symptoms were attributed to noise and who heard low noise spent more time in shock avoidance than the other three groups. Again there was no evidence of misattribution of arousal. The results are interpreted as indicating that the results of misattribution studies are best explained in terms of the presentation of arousal information in a plausible context.     

Effect of attention control on sustained attention during induced anxiety

Anxiety has wide-reaching and complex effects on cognitive performance. Although it can intrude on cognition and interfere with performance, it can also facilitate information processing and behavioural responses. In a previous study, we showed that anxiety induced by threat of shock facilitates performance on the Sustained Attention to Response Task, a vigilance test, which probes response inhibition to infrequent nogo stimuli. The present study sought to identify factors that may have contributed to such improved performance, including on- and off-task thinking (assessed with thought probes) and individual differences in attention control, as measured with the Attention Control Scale. Replicating our prior finding, we showed that shock threat significantly reduced errors of commission on the nogo trials. However, we extended this finding in demonstrating that this effect was driven by subjects with low attention control. We therefore confirm that anxiety increases inhibitory control of prepotent responses—a mechanism which is adaptive under threat—and show that this effect is greater in those who rely more upon such prepotent responding, i.e., those with low attentional control.