Andrew Mathews

The Emotional Stroop Task and Psychopathology

Attentional bias is a central feature of many cognitive theories of psychopathology. One of the most frequent methods of investigating such bias has been an emotional analog of the Stroop task. In this task, participants name the colors in which words are printed, and the words vary in their relevance to each theme of psychopathology. The authors review research showing that patients are often slower to name the color of a word associated with concerns relevant to their clinical condition. They address the causes and mechanisms underlying the phenomenon, focusing on J.D. Cohen, K. Dunbar, and J.L. McClellands (1990) parallel distributed processing model.

Brief standard self-rating for phobic patients.

Summary A one-page self-rating form is described to monitor change in phobic patients. It is derived from earlier versions used in 1000 phobic club members and 300 phobic patients. The form yields four scores: main phobia, global phobia, total phobia and anxiety-depression. The total phobia score is composed of agoraphobia, social and blood-injury subgroups. The form is short, reliable and valid. Adoption of this standard form for research in clinical populations would facilitate comparison of results across centres and studies.

Selective processing of threat cues in anxiety states

It was postulated that generalized anxiety states are associated with selective processing of threat cues arising from the activity of cognitive structures concerned with processing information related to personal danger (danger schemata). Selective processing was investigated using a modification of the Stroop Colour-naming Task, in which some of the target words were related to physical or social threat, while others were completely unrelated to danger. Anxious Ss were generally slower than controls in colour-naming all words, but were particularly slow with threat words. In the case of physical (but not social) threat words, there was also evidence that interference was most marked in those Ss reporting worries within the relevant domain. Taken together with correlational findings that degree of slowing was associated with mood state, the results were interpreted as evidence that the individual content of danger schemata determine the type of material that is selectively processed, while the extent of interference observed depends on current anxiety level.

WHY WORRY? THE COGNITIVE FUNCTION OF ANXIETY

The phenomenon of worry is considered to arise from cognitive processes involved in anxiety, that serve to maintain high levels of vigilance for personal danger. Rather than rely on self-report alone, the research described here draws on information processing methodology, to investigate this hypothesized cognitive function. Evidence is summarized to show that anxious subjects selectively attend to threatening information, and interpret ambiguous events in a relatively threatening way. However, the evidence on memory suggests that although such information may be easily activated, it is not necessarily more accessible. The allocation of attentional priority to threatening information is seen as a characteristic of anxious (rather than depressed) mood, while the ease with which this processing mode is adopted may underlie trait anxiety and vulnerability to anxiety disorders.

Anxiety and the allocation of attention to threat.

Using a probe detection technique we have recently demonstrated that anxious subjects consistently deploy attention towards threat-related stimuli, whereas non-anxious controls tend to move attention away from such material (MacLeod, Mathews, & Tata, 1986). The current study employed the same paradigm but attempted to distinguish the role of trait and state anxiety by testing high- and low-trait students when state anxiety was relatively low (12 weeks before a major examination) and again when it was relatively high (one week before this examination). High-trait subjects alone tended to shift attention towards generally threatening material on both test occasions. Results for examination-related stimuli were more complex. Increased proximity to the examination was associated with an increase in attentional bias towards such threat stimuli in high-trait subjects, but with increased attentional avoidance of such stimuli in low-trait subjects. It is suggested that the attentional response to currently relevant stress-related stimuli may be associated with neither trait nor state anxiety alone, but with an interactive function involving both these variables. These results are discussed in relation to existing models of emotion and cognition, and alternative interpretations of the findings are considered.

Cognitive processes in anxiety

Abstract Clinical reports suggest that anxiety states are associated with cognitions concerning danger. Since judgements of the risk of an event are thought to be influenced by judgemental heuristics such as availability of cognitive representations of such events, it was hypothesised that anxious individuals should overestimate subjective personal risk. This was confirmed in a comparison with matched control subjects, although patients who were also depressed as well as anxious over-estimated risks to at least the same extent. Results were interpreted as supporting an interaction between anxiety and the availability of ‘danger schemata’.

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 processing biases have causal effects on anxiety

After briefly describing the nature of emotional processing biases associated with vulnerability to anxiety, and a model of how they may be produced, we review new data on the experimental induction of attentional and interpretative biases. We show that these biases can be readily induced in the laboratory, in the absence of mood changes. However, induced biases exert effects on the processing of new information and cause congruent changes in state anxiety when they influence how emotionally significant information is encoded. We can therefore conclude that biases have causal effects on vulnerability to anxiety via their influence on how significant events are processed. Finally, we discuss how our model might account for the acquisition of processing bias and for when they can influence anxiety.

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.

Subliminal processing of emotional information in anxiety and depression.

The study investigated selective processing of emotional information in anxiety and depression using a modified Stroop color naming task. Anxious (n = 19), depressed (n = 18), and normal control (n = 18) subjects were required to name the background colors of anxiety-related, depression-related, positive, categorized, and uncategorized neutral words. Half of the words were presented supraliminally, half subliminally. Anxious subjects, compared with depressed and normal subjects, showed relatively slower color naming for both supraliminal and subliminal negative words. The results suggest a preattentive processing bias for negative information in anxiety.