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Biomedical subjects

David M Clark

Publications and source records attributed to David M Clark.

At least 19 recordsLinked to original sources
PubMed2007

Perception of arousal in social anxiety: effects of false feedback during a social interaction.

Cognitive models suggest that during social interactions, socially anxious individuals direct their attention to internal cues of arousal and use this information to erroneously infer how they appear to others. High (N=36) and low (N=36) socially anxious adults had a conversation with a stooge, and were led to believe by false feedback that they were experiencing either an increase or decrease in arousal, or evaluating the comfort level of the feedback equipment. Compared to the other groups, participants who believed their arousal had increased, reported greater anxiety, poorer perceived performance, more physical cues of anxiety, and greater underestimation of their performance and overestimation of the visibility of their anxiety. The effects were not specific to participants with high social anxiety. Observers rated the behaviour of participants who believed that their arousal had decreased most favourably. The results have implications for the treatment of social phobia.

Adult↗
PubMed2007

Rumination in posttraumatic stress disorder.

Recent studies have shown that rumination is a powerful predictor of persistent posttraumatic stress disorder (PTSD). However, to date, the mechanisms by which rumination maintains PTSD symptoms are little understood. Two studies of assault survivors, a cross-sectional (N = 81) and a 6-month prospective longitudinal study (N = 73), examined several facets of ruminative thinking to establish which aspects of rumination provide the link to PTSD. The current investigation showed that rumination is not only used as a strategy to cope with intrusive memories but it also triggers such memories. Certain characteristics of rumination, such as compulsion to continue ruminating, occurrence of unproductive thoughts, and "why" and "what if" type questions, as well as negative emotions before and after rumination, were significantly associated with PTSD, concurrently and prospectively. These characteristics explained significantly more variance in PTSD severity than the mere presence of rumination, thereby indicating that not all ways of ruminative thinking are equally maladaptive.

Adult↗
PubMed2006

Inducing an interpretation bias changes self-imagery: a preliminary investigation.

Prior work suggests that variations in self-imagery can influence the emotional interpretations people make about social situations. The current experiment investigated the converse possibility: that inducing an inferential bias can change the content of self-related images. The effects of repeated practice in accessing either negative or positive social outcomes was tested by having participants report on self-images generated during subsequent experience with ambiguous social situations. Participants and independent judges rated the content of participants' self-images as being more negative after prior practice in accessing negative rather than positive social outcomes. Furthermore, participants who practiced accessing negative outcomes rated their anticipated anxiety in an imagined stressful social situation as being greater, and their expected social performance as poorer than participants in the positive outcome group. Groups did not differ in state anxiety levels when making their ratings, so it is unlikely that any observed differences between groups can be attributed to mood effects. We suggest that this finding is consistent with the hypothesis that inferential biases and content of self-images can interact with each other and may together serve to maintain social anxiety.

Adolescent↗
PubMed2006

Imagery and interpretations in social phobia: support for the combined cognitive biases hypothesis.

Cognitive-behavioral models of clinical problems typically postulate a role for the combined effects of different cognitive biases in the maintenance of a given disorder. It is striking therefore that research has tended to examine cognitive biases in isolation rather than assessing how they work together to maintain psychological dysfunction. The combined cognitive biases hypothesis presented here suggests that cognitive biases influence each another and can interact to maintain a given disorder. Furthermore, it is proposed that the combined effects of cognitive biases may have a greater impact on sustaining a given disorder than if the biases operated in isolation. The combined cognitive biases hypothesis is examined in relation to imagery and interpretation in social phobia. Individuals with social phobia experience negative images of themselves performing poorly in social situations, and they also interpret external social information in a less positive way than those without social anxiety. Evidence of a reciprocal relationship between imagery and interpretations is presented, and the mechanisms underlying the combined effects are discussed. Clinical implications and the potential utility of examining the combined influence of other cognitive biases are highlighted.

Affective Symptoms↗
PubMed2006

Reduced heart rate responding to trauma reliving in trauma survivors with PTSD: correlates and consequences.

The authors investigated whether heart rate (HR) responses to voluntary recall of trauma memories (a) are related to posttraumatic stress disorder (PTSD), and (b) predict recovery 6 months later. Sixty-two assault survivors completed a recall task modeled on imaginal reliving in the initial weeks postassault. Possible cognitive modulators of HR responsivity were assessed; dissociation, rumination, trauma memory disorganization. Individuals with PTSD showed a reduced HR response to reliving compared to those without PTSD, but reported greater distress. Notably, higher HR response but not self-reported distress during reliving predicted greater symptom reduction at follow-up in participants with PTSD. Engagement in rumination was the only cognitive factor that predicted lower HR response. The data are in contrast to studies using trauma reminders to trigger memories, which have found greater physiological reactivity in PTSD. The authors' observations are consistent with models of PTSD that highlight differences between cued or stimulus-driven retrieval and intentional trauma recall, and with E. B. Foa and M. J. Kozak's (1986) hypothesis that full activation of trauma memories facilitates emotional processing.

Adolescent↗
PubMed2006

Changes in intrusive memories associated with imaginal reliving in posttraumatic stress disorder.

The study investigated changes in intrusive memories associated with imaginal reliving of traumatic events in posttraumatic stress disorder (PTSD). The study population comprised 44 patients treated with imaginal reliving in the context of cognitive therapy for PTSD [Behav. Res. Ther. 38 (2000) 319-345]. For most patients, imaginal reliving did not lead to exacerbations in intrusion frequency. The decrease in intrusion frequency after reliving was gradual, as was the decrease in their distress, vividness, and perceived "nowness." Poorer outcome, i.e., a smaller reduction in residual gain scores for intrusion frequency with reliving, was associated with greater initial PTSD severity, greater anger, greater perceived "nowness" of intrusive memories, and more negative interpretations of PTSD symptoms. The patient's anxiety, depression, self-blame, and dissociation were not predictive of response to reliving.

Adult↗
PubMed2006

The causal role of negative imagery in social anxiety: a test in confident public speakers.

This study tests the causal role of negative self-imagery in social anxiety. Low public-speaking anxious volunteers rehearsed a negative self-image, a positive self-image or a control image prior to giving a speech. As predicted, the negative image group felt more anxious, believed they performed less well and reported more negative thoughts than the positive image group. These findings do not appear to be due to changes in state anxiety, since they remained unchanged when anxiety was controlled in an analysis of covariance. The negative image group also reported more anxiety than the control group. Given that participants do not currently have anxiety problems, the findings are consistent with the idea that negative self-imagery has a causal role in the development and maintenance of social anxiety.

Affect↗
PubMed2006

Cognitive therapy versus exposure and applied relaxation in social phobia: A randomized controlled trial.

A new cognitive therapy (CT) program was compared with an established behavioral treatment. Sixty-two patients meeting Diagnostic and Statistical Manual of Mental Disorders (4th ed.; American Psychiatric Association, 1994) criteria for social phobia were randomly assigned to CT, exposure plus applied relaxation (EXP = AR), or wait-list (WAIT). CT and EXP = AR were superior to WAIT on all measures. On measures of social phobia, CT led to greater improvement than did EXP = AR. Percentages of patients who no longer met diagnostic criteria for social phobia at posttreatment-wait were as follows: 84% in CT, 42% in EXP = AR, and 0% in WAIT. At the 1-year follow-up, differences in outcome persisted. In addition, patients in EXP = AR were more likely to have sought additional treatment. Therapist effects were small and nonsignificant. CT appears to be superior to EXP = AR in the treatment of social phobia.

Adult↗
PubMed2006

An experimental study on fear of public speaking using a virtual environment.

This paper examines a necessary condition for successful exploitation of a virtual environment (VE) in therapeutic intervention for fear of public speaking. The condition is that clients experience a degree of anxiety in the VE that is similar to what they would have been expected to experience in a similar real world setting. We refer to this as a "presence" response. The experimental study involved 20 people who were confident public speakers and 16 who were phobic, assessed on a standard psychological scale. Half of each group spoke within a VE depicting an empty seminar room, and the other half within the same room but populated by a neutrally behaving virtual audience of five people. Three responses were measured--a questionnaire-based measure of anxiety, a measure of self-focused attention on somatic responses, and actual heart rate. On all responses, the people with phobia showed a significant increase in signs of anxiety when speaking to the virtual audience compared to the empty room, whereas the confident people did not. The result was strong in spite of the relatively low representational and behavioral fidelity of the virtual characters.

Adult↗
PubMed2006

Preliminary evidence for an association between social anxiety symptoms and avoidance of negative faces in school-age children.

Attentional biases with regard to emotional facial expressions are associated with social anxiety in adults. We investigated whether similar relations exist in children. Seventy-nine 8- to 11-year-olds completed a probe detection task. On a given trial, 1 of 3 pairs of faces was presented: negative-neutral, negative-positive, and positive-neutral. The strongest association was between social anxiety symptoms and avoidance of negative faces from negative-neutral trials (r = - .32), with all other correlations less than half that size. This association was largely due to avoidance of angry and fearful expressions. These results provide preliminary evidence that anxiety is associated with attentional biases in children as in adults.

Anger↗
PubMed2005

Cognitive therapy for post-traumatic stress disorder: development and evaluation.

The paper describes the development of a cognitive therapy (CT) program for post-traumatic stress disorder (PTSD) that is based on a recent cognitive model (Behav. Res. Therapy 38 (2000) 319). In a consecutive case series, 20 PTSD patients treated with CT showed highly significant improvement in symptoms of PTSD, depression and anxiety. A subsequent randomized controlled trial compared CT (N = 14) and a 3-month waitlist condition (WL, N = 14). CT led to large reductions in PTSD symptoms, disability, depression and anxiety, whereas the waitlist group did not improve. In both studies, treatment gains were well maintained at 6-month follow-up. CT was highly acceptable, with an overall dropout rate of only 3%. The intent-to-treat effect sizes for the degree of change in PTSD symptoms from pre to post-treatment were 2.70-2.82 (self-report), and 2.07 (assessor-rated). The controlled effect sizes for CT versus WL post-treatment scores were 2.25 (self-report) and 2.18 (assessor-rated). As predicted by the cognitive model, good treatment outcome was related to greater changes in dysfunctional post-traumatic cognitions. Patient characteristics such as comorbidity, type of trauma, history of previous trauma, or time since the traumatic event did not predict treatment response, however, low educational attainment and low socioeconomic status were related to better outcome.

Adolescent↗
PubMed2004

Developing new treatments: on the interplay between theories, experimental science and clinical innovation.

It is often argued that behaviour therapy and cognitive-behaviour therapy have a sound theoretical and experimental basis. In the early days of behaviour therapy, the learning theory accounts that were the basis of treatment made clear suggestions about the procedures that were likely to be effective in treatment. In contrast, more recent cognitive-behavioural models tend to specify targets for therapy, but not the procedures that might be optimal for changing the targets. As a consequence, a considerable amount of work has to be done in order to create an effective cognitive-behavioural treatment from a promising cognitive-behavioural model. The process by which cognitive-behavioural treatments are developed is rarely discussed in the literature. For this reason, the way in which one group has used a mixture of phenomenological, experimental and treatment development studies to create effective cognitive therapy programmes for anxiety disorders is described.

Anxiety Disorders↗
PubMed2004

Information-processing bias in social phobia.

Social phobia is a persistent disorder that is unlikely to be maintained by avoidance alone. One reason for the enduring nature of social phobia may be the way individuals with the disorder process social information. It is important for those involved in social phobia to have an understanding of information-processing biases, because it has the potential to guide psychological interventions. In this review of social phobia, probability and cost estimates of social situations are examined, interpretive biases are evaluated and findings relating to memory and negative imagery are also reviewed. The clinical implications of social-phobia-related information-processing biases are discussed and possible avenues for future research are outlined.

Autobiographies as Topic↗
PubMed2004

Heart-beat perception, panic/somatic symptoms and anxiety sensitivity in children.

There is considerable evidence implicating heart-beat perception (HBP) accuracy and anxiety sensitivity (AS) in the development of panic in adults. However, to date there have been no studies exploring the association between HBP, AS and childhood panic/somatic symptoms. Seventy-nine children aged 8 to 11 years completed a mental tracking paradigm (Psychophysiology 18 (1981) 483) to assess HBP, the Children's Anxiety Sensitivity Index (J Clin Chil Psychol 20 (1991) 162) and the Screen for Childhood Anxiety Related Emotional Disorders (J Am Acad Child Adoles Psych 38 (1999) 1230). Those with good HBP (n = 7, 9%) had significantly higher panic/somatic symptoms (t = -1.71, P < 0.05), and AS (t = -2.16, P < 0.02) than those with poor HBP. There were no effects of age, sex or BMI on HBP. Those with high levels of panic/somatic symptoms were seven times more likely to have good HBP and had AS scores 1 S.D. higher than the remainder of the sample. Multivariate analyses revealed that these two phenotypes had independent associations with high panic/somatic symptoms. These results extend the literature on HBP and panic and suggest that in children, as in adults, increased panic/somatic symptoms are associated with enhanced ability to perceive internal physiological cues, and fear of such sensations.

Anxiety Disorders↗
PubMed2004

Characteristics and content of intrusive memories in PTSD and their changes with treatment.

Although intrusive reexperiencing is a core symptom of postraumatic stress disorder (PTSD), relatively little is known about its phenomenology. The present study assessed the characteristics and content of intrusive trauma memories in 22 patients with PTSD, and followed their changes in the course of cognitive behavioral treatment. Patients had a small number of different intrusive memories (1-4, M = 2.2) that occurred in an invariable, repetitive way. The intrusions were distressing and had a vivid perceptual content. They appeared to the patient to be happening in the "here and now." With therapy, the frequency, vividness, distress, and nowness of the intrusions faded gradually. There was no exacerbation with imaginal reliving. The content of intrusions was classified by raters to test A. Ehlers et al.'s (2002) hypothesis that intrusive memories are usually of warning stimuli that signalled the moments with the greatest emotional impact. The results were consistent with this hypothesis.

Adult↗
PubMed2004

Negative self-imagery in social anxiety contaminates social interactions.

Patients with social phobia report experiencing negative images of themselves performing poorly when in feared social situations. The present study investigates whether such negative self-imagery (based on memory of past social situations) contaminates social interactions. High socially anxious volunteers participated in two conversations with another volunteer (conversational partner). During one conversation, the socially anxious volunteers held in mind a negative self-image, and during the other they held in mind a less negative (control) self-image. As predicted, when holding the negative image the socially anxious volunteers felt more anxious, reported using more safety behaviours, believed that they performed more poorly, and showed greater overestimation of how poorly they came across (relative to ratings by the conversational partner). Conversational partners rated the socially anxious volunteers' performance as poorer in the negative image condition. Furthermore, the conversation was contaminated since both groups of participants rated its quality as poorer in the negative image condition.

Analysis of Variance↗
PubMed2003

A randomized controlled trial of cognitive therapy, a self-help booklet, and repeated assessments as early interventions for posttraumatic stress disorder.

BACKGROUND: It is unclear what psychological help should be offered in the aftermath of traumatic events. Similarly, there is a lack of clarity about the best way of identifying people who are unlikely to recover from early posttraumatic symptoms without intervention. OBJECTIVE: To determine whether cognitive therapy or a self-help booklet given in the initial months after a traumatic event is more effective in preventing chronic posttraumatic stress disorder (PTSD) than repeated assessments. DESIGN: Randomized controlled trial. Patients Motor vehicle accident survivors (n = 97) who had PTSD in the initial months after the accident and met symptom criteria that had predicted persistent PTSD in a large naturalistic prospective study of a comparable population. SETTING: Patients were recruited from attendees at local accident and emergency departments. INTERVENTIONS: Patients completed a 3-week self-monitoring phase. Those who did not recover with self-monitoring (n = 85) were randomly assigned to receive cognitive therapy (n = 28), a self-help booklet based on principles of cognitive behavioral therapy (n = 28), or repeated assessments (n = 29). MAIN OUTCOME MEASURES: Symptoms of PTSD as assessed by self-report and independent assessors unaware of the patient's allocation. Main assessments were at 3 months (posttreatment, n = 80) and 9 months (follow-up, n = 79). RESULTS: Twelve percent (n = 12) of patients recovered with self-monitoring. Cognitive therapy was more effective in reducing symptoms of PTSD, depression, anxiety, and disability than the self-help booklet or repeated assessments. At follow-up, fewer cognitive therapy patients (3 [11%]) had PTSD compared with those receiving the self-help booklet (17 [61%]; odds ratio, 12.9; 95% confidence interval, 3.1-53.1) or repeated assessments (16 [55%]; odds ratio, 10.3; 95% confidence interval, 2.5-41.7). There was no indication that the self-help booklet was superior to repeated assessments. On 2 measures, high end-state functioning at follow-up and request for treatment, the outcome for the self-help group was worse than for the repeated assessments group. CONCLUSIONS: Cognitive therapy is an effective intervention for recent-onset PTSD. A self-help booklet was not effective. The combination of an elevated initial symptom score and failure to improve with self-monitoring was effective in identifying a group of patients with early PTSD symptoms who were unlikely to recover without intervention.

Accidents, Traffic↗