Attentional biases in PTSD: More evidence for interference

Attentional biases to trauma-related stimuli have been widely demonstrated in individuals with posttraumatic stress disorder (PTSD). However, the majority of these studies used methods not suited to differentiating difficulty disengaging attention from threatening stimuli (interference) from facilitated detection of threat. In the current study, a visual search task (VST) with a lexical decision component was used to differentiate between attentional interference and facilitation. Forty-six sexual assault survivors with High PTSD or Low PTSD symptoms completed the VST with three types of stimuli (trauma-related, general threat-related, and semantically-related neutral words), to examine the specificity of attentional biases associated with PTSD symptoms. High PTSD participants showed increased interference to trauma-related words relative to Low PTSD participants. Furthermore, the increased attentional interference in High PTSD participants was specific to trauma-related stimuli. No evidence was found for facilitated detection of threatening stimuli in PTSD. These results provide additional support for attentional biases in PTSD relating to attentional interference with trauma-related cues rather than facilitated detection of threat. The implications for this pattern of results are discussed in relation to anxiety disorders that are characterized by rumination and/or intrusions (e.g., PTSD, GAD) rather than those more circumscribed to fight or flight response (e.g., phobias).     

PTSD and Emotional Distress Symptoms Measured After a Motor Vehicle Accident: Relationships with Pain Coping Profiles

This study explored differences among pain patients classified as Dysfunctional, Interpersonally Distressed, and Adaptive Copers on the Multidimensional Pain Inventory with respect to PTSD symptomatology, anxiety, and depression. Eighty-five patients with pain complaints who had experienced a serious motor vehicle accident were classified into these three pain coping categories and assessed using clinician and self-report measures. Results indicated that patients classified as Adaptive Copers (n = 24) showed less PTSD symptomatology, anxiety, and depressed mood, relative to individuals classified as Dysfunctional (n = 36) and as Interpersonally Distressed (n = 25), who did not differ on these dimensions. Emotional responses during the accident (fear, helplessness, danger, perceived control, and certainty that one would die) did not differentiate the groups. Pain profiles contributed to the prediction of self-reported PTSD symptoms, controlling for state anxiety. These data suggest that pain patients with both Dysfunctional and Interpersonally Distressed coping profiles are at elevated risk for a range of posttrauma problems following a serious motor vehicle accident.     

Regional brain electrical activity in posttraumatic stress disorder after motor vehicle accident

This study examined whether patients with posttraumatic stress disorder (PTSD) related to motor vehicle accidents (MVAs) would show an abnormal pattern of electroencephalographic (EEG) alpha asymmetries, which has been proposed for particular types of anxiety. Patients with PTSD (n = 22) or subsyndromal PTSD (n = 21), traumatized controls without PTSD (non-PTSD with MVA; n = 21), and healthy controls without MVA (n = 23) underwent measurement of EEG activity during baseline and exposure to a neutral, a positive, a negative, and an accident-related picture. Differences in brain asymmetry between groups were observed only during exposure to trauma-related material. PTSD and subsyndromal PTSD patients showed a pattern of enhanced right anterior and posterior activation, whereas non-PTSD with MVA participants showed the opposite pattern. Furthermore, posterior asymmetry in nontraumatized healthy controls varied with gender, with female participants showing a pattern of higher right posterior activation. The results support the hypothesis that symptomatic MVA survivors are characterized by a pattern of right hemisphere activation that is associated with anxious arousal and symptoms of PTSD during processing of trauma-specific information.     

Effect of trait anger on cognitive processing of emotional stimuli

In the present experiment, the authors examined whether trait anger was associated with cognitive biases for anger-related semantic stimuli. Fifty-two undergraduate students completed the Trait Anger Scale (TAS; C. D. Spielberger, G. Jacobs, S. Russell, & R. Crane, 1983), and those reporting TAS scores in the upper (n = 17) or lower (n = 13) quartiles of the sample were assigned to high- and low-anger groups, respectively. The 30 participants then engaged in a lexical decision task that presented various emotion words, neutral words, and nonwords. Results indicated that individuals who reported high levels of trait anger displayed facilitative biases in the processing of semantic anger-related stimuli. This predisposition to more readily process anger-related information may underlie their propensity to experience intense feelings of anger when provoked.     

Examination of the Relationship Between PTSD and Distress Tolerance in a Sample of Male Veterans With Comorbid Substance Use Disorders

Distress tolerance (DT), the perceived or actual ability to tolerate negative emotional or physical states, is inversely related to posttraumatic stress disorder (PTSD) symptoms in civilian, community samples. No studies to date have examined the relationship between DT and PTSD in clinical samples of veterans with a comorbid diagnosis of PTSD and a substance use disorder (SUD). Thus, the present study examined the relationship between DT and PTSD in a sample of predominately African American, male veterans (n = 75) diagnosed with comorbid PTSD and SUD (according to a structured clinical interview). Results of hierarchical linear regression models indicated that DT was inversely related to total PTSD symptom severity score, above and beyond depressive symptoms and SUD severity. Of the 4 symptom clusters, DT was inversely associated with intrusions and hyperarousal. These findings are discussed in light of previous work with civilian samples. Determining whether treatment incorporating DT skills would be useful for veterans undergoing PTSD treatment should be evaluated.     

Posttraumatic stress disorder and psychosocial functioning within two samples of MVA survivors

To examine criterion F variables of PTSD, the psychosocial functioning of two samples of motor vehicle accident (MVA) survivors was investigated. Within each sample, comparisons between MVA survivors with and without PTSD were conducted on four psychosocial functioning indices at three time points. In addition, the relationships between specific PTSD symptom clusters and psychosocial functioning indices were examined. The study revealed that, in general, MVA survivors with PTSD evidenced poorer psychosocial functioning than did survivors without PTSD. The emotional numbing symptoms of PTSD emerged as the most consistent predictors of the psychosocial functioning indices. The implications of these findings to the comprehensive treatment of PTSD are discussed.     

Strategic and automatic threat processing in chronic musculoskeletal pain: a startle probe investigation

Attentional bias research with chronic pain samples has yielded conflicting results. In the present investigation the startle paradigm was used to test the postulate that fear-based mechanisms play an important role in attentional biases for pain-related threat in chronic pain. Participants, including 31 individuals with chronic musculoskeletal pain and 20 healthy controls, completed a startle task designed to measure attention to different types of words (neutral vs sensory pain vs affective pain vs health catastrophe) presented at different levels of cognitive processing (strategic vs automatic). Measures of fear-based individual difference variables, including anxiety sensitivity and fear of pain, were also completed. Startle amplitudes and latencies to acoustic startle probes that followed word presentations were recorded. Data were analyzed with repeated measures ANOVAs and correlational analysis. Significant between-group differences were found indicating that, relative to chronic pain participants, healthy controls had higher startle amplitude index scores for health catastrophe words. There was also a trend among patients with chronic pain for greater startle amplitude index scores for strategic presentations of sensory pain words. In the automatic condition, all participants demonstrated a lower startle latency index for sensory words relative to both affect and health catastrophe words, suggesting participants had more difficulty disengaging from affect and health catastrophe words or were more avoidant of sensory words. Correlational analyses indicated that startle response indices for words related to health catastrophe became more pronounced for chronic pain patients as anxiety sensitivity and fear of pain increased. Implications and directions for future research are discussed.     

Cognitive interference for trauma cues in sexually abused adolescent girls with posttraumatic stress disorder

Investigated cognitive processing of fear-relevant information in sexually abused adolescent girls with posttraumatic stress disorder (PTSD) using a modified Stroop procedure (MSP). Participants were 20 sexually abused girls with PTSD, 13 sexually abused girls without PTSD, and 20 nonvictimized girls who served as controls, 11 to 17 years old. Word conditions included abuse-related threat, developmentally relevant (related to the experience of sexual abuse, e.g., trust, secrecy, and intimacy), general threat, positive, and neutral. Girls with PTSD were expected to show cognitive interference for trauma-related words as well as for developmentally relevant words, relative to adolescents without PTSD. Overall color naming was significantly slower in the PTSD group than in the nonabused controls. Contrary to expectation, all participants demonstrated cognitive interference for trauma-related words. Relevant theoretical and methodological issues are highlighted.     

Pupil-BLAH-metry: Cognitive effort in speech planning reflected by pupil dilation

In reading research, a longstanding question is whether any stages of lexical processing require central attention, and whether such potential demands are frequency-sensitive. In the present study, we examined the allocation of cognitive effort in lexical processing by examining pupil dilations and naming latencies in a modified delayed naming procedure. In this dual-task/change procedure, participants read words and waited for various delays before being signaled to issue a response. On most trials (80%), participants issued a standard naming response. On the remaining trials, they were cued to abandon the original speech plan, saying "blah" instead, thereby equating production across different words. Using feature-matched low- and high-frequency words, we observed the differences in pupil dilations as a function of word frequency. Indeed, frequency-sensitive cognitive demands were seen in word processing, even after naming responses were issued. The results suggest that word perception and/or speech planning requires the frequency-sensitive allocation of cognitive resources.     

Altered processing of health threat words as a function of hypochondriacal tendencies and experimentally manipulated control beliefs

Attentional biases associated with various forms of psychopathology have been well documented. Few studies, however, have assessed the factors that moderate these biases. The present paper assesses the biased processing of health words as a function of hypochondriacal tendencies during a threat of bioterrorism (anthrax), and whether perceived control can moderate those biases. Based on a sample of 328 participants, hypochondriacal tendencies were associated with slower reaction times on a modified emotional Stroop task when the stimulus words were anthrax-related, and this effect was moderated by a manipulation of perceived control. Specifically, individuals with low perceived control over the health threat had greater attentional bias of anthrax infection, independent of related variables such as anxiety.     

Strategic and Automatic Threat Processing in Chronic Musculoskeletal Pain: A Startle Probe Investigation

Attentional bias research with chronic pain samples has yielded conflicting results. In the present investigation the startle paradigm was used to test the postulate that fear‐based mechanisms play an important role in attentional biases for pain‐related threat in chronic pain. Participants, including 31 individuals with chronic musculoskeletal pain and 20 healthy controls, completed a startle task designed to measure attention to different types of words (neutral vs sensory pain vs affective pain vs health catastrophe) presented at different levels of cognitive processing (strategic vs automatic). Measures of fear‐based individual difference variables, including anxiety sensitivity and fear of pain, were also completed. Startle amplitudes and latencies to acoustic startle probes that followed word presentations were recorded. Data were analyzed with repeated measures ANOVAs and correlational analysis. Significant between‐group differences were found indicating that, relative to chronic pain participants, healthy controls had higher startle amplitude index scores for health catastrophe words. There was also a trend among patients with chronic pain for greater startle amplitude index scores for strategic presentations of sensory pain words. In the automatic condition, all participants demonstrated a lower startle latency index for sensory words relative to both affect and health catastrophe words, suggesting participants had more difficulty disengaging from affect and health catastrophe words or were more avoidant of sensory words. Correlational analyses indicated that startle response indices for words related to health catastrophe became more pronounced for chronic pain patients as anxiety sensitivity and fear of pain increased. Implications and directions for future research are discussed.     

Conceptual and perceptual priming and dissociation in chronic posttraumatic stress disorder

Cognitive models of posttraumatic stress disorder (PTSD) assert that memory processes play a significant role in PTSD (see e.g., Ehlers & Clark, 2000). Intrusive reexperiencing in PTSD has been linked to perceptual processing of trauma-related material with a corresponding hypothesized lack of conceptual processing. In an experimental study that included clinical participants with and without PTSD (N = 50), perceptual priming and conceptual priming for trauma-related, general threat, and neutral words were investigated in a population with chronic trauma-induced complaints as a result of the Troubles in Northern Ireland. The study used a new version of the word-stem completion task (Michael, Ehlers, & Halligan, 2005) and a word-cue association task. It also assessed the role of dissociation in threat processing. Further evidence of enhanced perceptual priming in PTSD for trauma stimuli was found, along with evidence of lack of conceptual priming for such stimuli. Furthermore, this pattern of priming for trauma-related words was associated with PTSD severity, and state dissociation and PTSD group made significant contributions to predicting perceptual priming for trauma words. The findings shed light on the importance of state dissociation in trauma-related information processing and posttraumatic symptoms.     

Evidence of a disposition toward fearfulness and vulnerability to posttraumatic stress in dysfunctional pain patients

Few investigations have addressed whether patient subgroups derived using the Multiaxial Assessment of Pain (MAP) [Turk, D. C., & Rudy, T. E. (1987). Towards a comprehensive assessment of chronic pain patients. Behaviour Research and Therapy, 25, 237-249; Turk, D. C., & Rudy, T. E. (1988). Toward an empirically derived taxonomy of chronic pain patients: integration of psychological assessment data. Journal of Consulting and Clinical Psychology, 56, 233-238.] differ with regard to fear and avoidance. It has, however, been reported that dysfunctional patients exhibit more pain-specific fear and avoidance than patients classified as interpersonally distressed or minimizers/adaptive copers [Asmundson, G. J. G., Norton, G. R., & Allerdings, M. D. (1997). Fear and avoidance in dysfunctional chronic back pain patients. Pain, 69, 231-236.]. We attempted to extend these findings by examining two fear constructs that are receiving increased attention in the chronic pain literature-anxiety sensitivity and PTSD. The sample comprised 115 patients with chronic pain. Of these, 14 (12.2%) were classified as dysfunctional, 21 (18.3%) as interpersonally distressed and 47 (40.8%) as minimizers/adaptive copers. Between-group differences were observed on the fear of cognitive and emotional dyscontrol dimension of anxiety sensitivity, total and symptom cluster scores on the PTSD measure, and depression. No differences were observed for the fear of somatic sensations dimension of anxiety sensitivity or agoraphobia, social phobia, and blood/injury fears. Dysfunctional patients generally exhibited elevated scores relative to one or both of the other MAP subgroups on fear of cognitive and emotional dyscontrol, depressed affect, PTSD symptom total score and PTSD symptom cluster scores. As well, a substantial proportion of dysfunctional and interpersonally distressed patients were classified as having PTSD (71.4 and 42.9%, respectively) when compared to minimizers/adaptive copers (21.3%). These results suggest that MAP subgroups differ with regard to their propensity to be(come) fearful and in their likelihood of having PTSD. Theoretical and clinical implications are discussed.     

Depth of processing and recall of threat material in fearful and nonfearful individuals

Although many studies have examined the nature of memory distortions in anxious individuals, few have considered biases in specific memory processes, such as encoding or retrieval. To investigate whether the presentation of threat material facilitates encoding biases, spider fearful (n=63), blood fearful (n=73), and nonfearful (n=75) participants encoded spider related, blood related, and neutral words as a function of three levels of processing (i.e., structural, semantic, and self referent). Participants subsequently completed either a free recall or a recognition task. All participants demonstrated a partial depth of processing effect, such that they recalled more words encoded in the self referent condition than in the other two conditions, but groups did not differ in their recall of stimuli as a function of word type. Relative to participants in the other groups, spider fearful participants had fewer spider related intrusions in the recall condition, and they made fewer errors in responding to structural and semantic encoding questions when spider related words were presented. These results contribute to an increasingly large body of literature suggesting that anxious individuals are not characterized by a memory bias toward threat, and they raise the possibility that individuals with spider fears process threat-relevant information differently than individuals with blood fears.     

When and why does abuse predict reduced autobiographical memory specificity?

Two studies were conducted to explore the conditions that elicit autobiographical memory problems in abuse victims and the mechanism that underlie them. In Study 1 older adolescents (n=80) with and without self-reported abuse histories completed a modified version of the Autobiographical Memory Test (AMT-U); participants were given an unlimited amount of time to provide specific memories in response to cue words. Participants also completed measures of depression and post-traumatic stress disorder (PTSD), working memory, and attentional biases. This study found that abuse severity and PTSD symptoms were positively related to memory specificity on the AMT-U. In Study 2 older adolescents (n=78) with and without self-reported abuse histories completed the traditional (timed) version of the AMT. Participants also completed measures of working memory, attentional biases, self-reported coping, and psychopathological symptoms (i.e., depression and PTSD). In this study the opposite relationship was observed, such that abuse severity was related to poorer memory specificity, but this relationship was explained by disengagement coping and PTSD symptoms. This work suggests that poor memory specificity may represent a form of avoidance, but the application of avoidant mechanisms depends on the remembering context.     

Work potential of road accident survivors with post-traumatic stress disorder

Work potential in adult survivors of road accidents with and without post-traumatic stress disorder (PTSD) was examined at a mean of 8.6 months (SD = 3.77) post-accident. All participants were working prior to their accident. Results showed that survivors with PTSD had significantly less work potential post-accident than survivors without PTSD. Specific barriers to employability for survivors with PTSD identified by this study included high levels of depression, reduced time-management ability, and an over-concern or anxiety with physical injuries. Respondents with PTSD, however, reported significantly greater extrinsic motivation to work than those without PTSD. Early intervention and referral to occupational rehabilitation programs that: (1) help address these barriers to employability and stimulate the existing motivation to return to work, and (2) work alongside clinical treatment programs, may assist in the reduction of poor work outcomes that people with PTSD following road accidents often experience.     

How do I appear to others? Social anxiety and processing of the observable self

Two information processing biases that could maintain social anxiety were investigated. High and low socially anxious individuals encoded positive and negative trait words in one of three ways: public self-referent, private self-referent, and other-referent. Half were then told they would soon have to give a speech. As predicted, compared to low socially anxious individuals, high socially anxious individuals recalled less positive public self-referent words, but only when both groups were anticipating giving a speech. No memory biases were observed for private self-referent or other-referent words. Next all participants gave a speech. Correlational analyses suggested that high socially anxious individuals may use the somatic concomitants of anxiety to overestimate how anxious they appear and underestimate how well they come across.     

Inhibitory control of threat remembering in PTSD

ABSTRACT

Intrusive traumatic recollections suggest an inability in Posttraumatic Stress Disorder (PTSD) to control and notably to inhibit memories for trauma-related information. Supported by inhibitory deficits found on experimental settings in PTSD, memory functioning and memory biases in the disorder were usually explained through inhibitory and control deficits in the processing of trauma-related information. The present study aimed to directly assess this hypothesis by investigating memory control abilities for emotional information in PTSD. For this purpose, 34 patients diagnosed with PTSD were compared to 37 non-PTSD controls on an item-cued directed forgetting paradigm for emotional words combined with a Remember/Know recognition procedure. Results revealed enhanced amounts of Remember recognitions for trauma-related words in PTSD. Moreover, we replicated findings of memory control impairments in the disorder. However, such impairments only occurred for non-trauma-related words. Accordingly, it appeared that PTSD patients presented preserved memory control abilities for trauma-related words, at the expenses of other emotional valences. Surprisingly, PTSD patients presented a preserved ability to control and notably to inhibit their memory functioning for trauma-related material. In addition to potential theoretical and clinical relevance, these results are discussed in the light of resource reallocation hypotheses and vigilant-avoidant theories of information processing in PTSD.     

Attention training normalises combat-related post-traumatic stress disorder effects on emotional Stroop performance using lexically matched word lists

We examined two groups of combat veterans, one with post-traumatic stress disorder (PTSD) (n?=?27) and another without PTSD (n?=?16), using an emotional Stroop task (EST) with word lists matched across a series of lexical variables (e.g. length, frequency, neighbourhood size, etc.). Participants with PTSD exhibited a strong EST effect (longer colour-naming latencies for combat-relevant words as compared to neutral words). Veterans without PTSD produced no such effect, t?p?>?.37. Participants with PTSD then completed eight sessions of attention training (Attention Control Training or Attention Bias Modification Training) with a dot-probe task utilising threatening and neutral faces. After training, participants—especially those undergoing Attention Control Training—no longer produced longer colour-naming latencies for combat-related words as compared to other words, indicating normalised attention allocation processes after treatment.     

Influence of affective distractors on working memory capacity in relation to symptoms of posttraumatic stress disorder

Symptoms evoked in individuals with posttraumatic stress disorder (PTSD) when processing trauma‐relevant material arguably impair higher order cognitive functions. An example is working memory capacity (WMC), which has been shown to be disrupted by affective distractors. However, it is unknown whether this association varies across different types of PTSD symptoms. This study explored the association between WMC performed in affective (relative to neutral) contexts in relation to different symptoms of PTSD (avoidance, re‐experiencing, hyperarousal). Motor vehicle accident survivors with PTSD and without PTSD completed a delayed‐match‐to‐sample task including trauma‐related, neutral, and scrambled distractors in the interval between the presentation of the memoranda and the recognition target. The results showed that there was support for an indirect pathway between PTSD diagnosis and WMC performed in affective (versus neutral) contexts through re‐experiencing and avoidance symptoms. The findings suggest that avoidance symptoms in particular may benefit from interventions directed at improving WMC.