Bundy Mackintosh

A Cognitive Model of Selective Processing in Anxiety

Anxiety states are associated with increasedattention to threat and a greater likelihood of reachinga pessimistic interpretation of ambiguous events.Existing models of this selective processing possess features that are difficult to reconcile withcurrent experimental findings. In this paper we build onthese earlier ideas to develop a new model,incorporating adaptations that allow it to accountbetter for the accumulating data. Essential featuresare that attributes or meanings of stimuli are processedin parallel and compete for attentional resources. Inputfrom a threat evaluation system (TES) strengthens activation of threat-related attributes, to anextent influenced by anxiety level. Such activation canbe countered, within limits, by voluntary task-relatedeffort, and the balance between these opposing influences determines the extent of anyattentional or interpretative bias seen. Such a model isplausible from an evolutionary perspective and isconsistent with neurological evidence concerning theacquisition and extinction of aversiveconditioning.

Induced emotional interpretation bias and anxiety.

Five experiments are reported showing that the interpretation of personally relevant emotional information can be modified by systematic exposure to congruent exemplars. Participants were induced to interpret ambiguous information in a relatively threatening or a benign way. Comparison with a baseline condition suggested that negative and positive induction had similar but opposing effects. Induction of an interpretative bias did not require active generation of personally relevant meanings, but such active processing was necessary before state anxiety changed in parallel with the induced interpretative bias. These findings provide evidence consistent with a causal link between the deployment of interpretative bias and anxiety and reveal something of the processes underlying this association.

The causal effect of mental imagery on emotion assessed using picture-word cues.

The hypothesis that mental imagery is more likely to elicit emotion than verbal processing of the same material was investigated in two studies. Participants saw a series of pictures, each accompanied by a word, designed to yield a negative or benign meaning when combined. Participants were either free to combine the picture and word as they wished (Experiment 1) or instructed to integrate them using either a descriptive sentence or a mental image (Experiment 2). Emotional response was consistently greater following imagery than after producing a sentence. Experiment 2 also demonstrated the causal effect of imagery on emotion and evaluative learning. Additional participants in Experiment 2 described aloud their images/sentences. Independent ratings of descriptions indicated that, as well as being more emotional, images differed from sentences elicited by identical cues by greater similarity to memories, and greater involvement of sensations and specific events. Results support the hypothesis that imagery evokes stronger affective responses than does verbal processing, perhaps because of sensitivity of emotional brain regions to imagery, the similarity of imagery to perception, and to autobiographical episodes.

Cognitive biases in anxiety and attention to threat

The existence of cognitive biases in anxiety is now well established, and we summarize evidence demonstrating attentional vigilance to cues associated with threat, pessimistic interpretation of ambiguous items and an increased perception of the likelihood of occurrence of negative events. We explore how these reactions can be understood within an evolutionary context, and present a descriptive model consistent with the experimental findings, conducive to modification of responses through learning. A computational implementation of aspects of the model successfully simulates changes in reaction time for a simple task as anxiety levels increase. Future directions include pursuing the causal nature of biases in anxiety and examining the potential for change through training techniques.

Cognitive bias modification for attention and interpretation reduces trait and state anxiety in anxious patients referred to an out-patient service: Results from a pilot study

It is well established that anxious individuals show biases in information processing, such that they attend preferentially to threatening stimuli and interpret emotional ambiguity in a threatening way. It has also been established that these biases in attention and interpretation can causally influence anxiety. Recent advances in experimental work have involved the development of a paradigm known as Cognitive Bias Modification (CBM), a constellation of procedures which directly modify bias using computerised tasks. Excitingly, these procedures have been shown to reduce bias in attention to threat (CBM-A), and to promote a positive interpretive bias (CBM-I) in anxious populations; furthermore, these modifications are associated with reductions in anxiety. We believe that these techniques have the potential to create a real clinical impact for people with anxiety. Initial studies involved volunteer participants who reached criteria for clinical diagnoses to be made, but emerging evidence suggests that patients referred for therapy also benefit. For the purposes of experimentation researchers have normally looked at one procedure at a time. In order to try to maximise the potential clinical impact we wished to investigate whether the combination of the procedures would be more effective than either alone. We also wished to investigate whether the procedures could be carried out in routine clinical settings with patients referred to an out-patient psychological treatment service. We therefore carried out a pilot study using a combined approach of CBM-A and CBM-I with a sample of 13 anxious patients referred to an out-patient psychology service for cognitive therapy. The results showed successful reductions in threat related attentional and interpretive bias, as well as reductions in trait and state anxiety. Participant reports describe the procedures as acceptable, with the attentional task experienced as boring, but the interpretive one experienced as helpful. While recognising the methodological problems of the pilot study we believe that these results give indications that the techniques could provide an effective intervention for anxiety, and that further study is well justified.

Anxiety and the deployment of visual attention over time

Two studies investigated the effects of anxiety on the time course of attention to threatening material. A rapid serial visual presentation (RSVP) paradigm required report of words belonging to a prespecified semantic category with a distractor placed at varying positions preceding the target. Where there was little resemblance in meaning between distractors and targets, threat distractors briefly captured the attention of high state anxious individuals but only after a delay. Where distractors resembled the meaning of the targets, attention was captured more immediately, but processing of threat-related material was concentrated at different points in time as a function of both the degree of semantic resemblance between distractors and target, and state anxiety. The extent to which distractors are salient to the experimental task influences attentional capture and the temporal course of processing. The methodological implications of these results are discussed together with a new hypothesis about the effects of state anxiety on attention.

A Comparison of Cognitive Bias Modification for Interpretation and Computerized Cognitive Behavior Therapy: Effects on Anxiety, Depression, Attentional Control, and Interpretive Bias

Objective: Computerized cognitive behavioral therapy (cCBT) and cognitive bias modification for interpretation (CBM-I) both have demonstrated efficacy in alleviating social anxiety, but how they compare with each other has not been investigated. The present study tested the prediction that both interventions would reduce anxiety relative to a no-intervention comparison condition, but CBM-I would be particularly effective at modifying threat-related cognitive bias under high mental load. Method: Sixty-three primarily Caucasian adults (mean age = 22.7, SD = 5.87; 68.3% female) with high social anxiety, randomly allocated to 3 groups: CBM-I (n = 21), cCBT (n = 21), and a no-intervention control group (n = 21) provided complete data for analysis. Pre- and postintervention (4 sessions lasting 2 weeks, control participants only attended the pre–post sessions) self-report measures of anxiety, depression, attentional control, and threat-related interpretive bias were completed. In addition, interpretive bias under high versus low cognitive load was measured using the Scrambled Sentences Test. Results: Both CBM-I and cCBT groups reported significantly reduced levels of social anxiety, trait anxiety, and depression and improved attentional control, relative to the control group, with no clear superiority of either active intervention. Although both active conditions reduced negative bias on the Scrambled Sentences Test completed under mental load, CBM-I was significantly more effective at doing so. Conclusions: The results suggest that although not differing in therapeutic efficacy, CBM-I and cCBT might differ in the resilience of their effects when under mental load.

Levels of specificity of autobiographical memories and of biographical memories of the deceased in bereaved individuals with and without complicated grief.

Traumatized individuals experiencing posttraumatic stress have difficulty retrieving specific autobiographical memories to cue words on the Autobiographical Memory Test (AMT; J. M. G. Williams & K. Broadbent, 1986). This may represent a generalized, functional avoidance of the personal past. However, such individuals also often report specific intrusive memories of their trauma in the day-to-day. This raises the possibility that memories tied to the source of the persons distress are immune to this putative avoidance process. This was investigated in bereaved individuals with complicated grief (CG) who reported intrusive, specific memories from the life of their deceased loved one, and matched bereaved controls without CG. Participants performed the AMT and two Biographical Memory Tests (BMTs), cueing memories from the life of the deceased (BMT-Deceased) and from a living significant other (BMT-Living). To negative word cues, the CG group showed reduced specificity for the AMT and BMT-Living, relative to controls, but this effect was reversed on the BMT-Deceased. These data support the proposal that memories tied to the source of an individuals distress are immune to the processes that underlie the standard reduced specificity effect.

Cognitive Bias Modification: The Critical Role of Active Training in Modifying Emotional Responses

Training participants to select threat or nonthreat interpretations of emotionally ambiguous stimuli or passively exposing them to valenced scenarios can modify later interpretation of ambiguity. However, only when encouraged to actively select meanings do congruent changes in emotional response occur during training itself (Mathews & Mackintosh, 2000). The present study assessed the more critical question of whether active training is also necessary for modifying subsequent emotional responses to images of new ambiguous scenarios presented after training. As predicted, active training did lead participants to rate their images of emotionally ambiguous scenarios as being more unpleasant after training as compared to a matched passive condition. This finding supports the view that active generation of meaning during interpretive training is critical for the modification of later emotional responses.

Ameliorating intrusive memories of distressing experiences using computerized reappraisal training.

The types of appraisals that follow traumatic experiences have been linked to the emergence of posttraumatic stress disorder (PTSD). Could changing reappraisals following a stressful event reduce the emergence of PTSD symptoms? The present proof-of-principle study examined whether a nonexplicit, systematic computerized training in reappraisal style following a stressful event (a highly distressing film) could reduce intrusive memories of the film, and symptoms associated with posttraumatic distress over the subsequent week. Participants were trained to adopt a generally positive or negative poststressor appraisal style using a series of scripted vignettes after having been exposed to highly distressing film clips. The training targeted self-efficacy beliefs and reappraisals of secondary emotions (emotions in response to the emotional reactions elicited by the film). Successful appraisal induction was verified using novel vignettes and via change scores on the post traumatic cognitions inventory. Compared with those trained negatively, those trained positively reported in a diary fewer intrusive memories of the film during the subsequent week, and lower scores on the Impact of Event Scale (a widely used measure of posttraumatic stress symptoms). Results support the use of computerized, nonexplicit, reappraisal training after a stressful event has occurred and provide a platform for future translational studies with clinical populations that have experienced significant real-world stress or trauma.