Claude M. Chemtob

A Cognitive Action Theory of Post- Traumatic Stress Disorder

Abstract Post-Traumatic Stress Disorder (PTSD) is an anxiety disorder characterized in part by such phenomena as intrusive memories, flashbacks, numbing of affect, memory and attentional impairment, hyperalartness, and adjustment difficulties. In this paper we describe a new theoretical approach to understanding PTSD in combat veterans that has implications for understanding PTSD resulting from other life-threatening situations, and for understanding other anxiety disorders and ordinary cognitive processes. Previous approaches to understanding PTSD have derived from associative learning theory, from a reinterpretation of psychodynamic theory, or from general notions of information processing. The perspective presented in this paper integrates these previous approaches and elaborates them into a hierarchical network view of cognition and action. According to this view, emotion, action, and memory all flow from the processing of information by specific mental network structures. The symptoms of PTSD are derived from structures that were acquired during combat because they were then adaptive in promoting the soldiers survival, but now lead to actions that are inappropriate for the civilian environment. The presence of these structures continues to produce difficulties for some individuals. Such occurs because they are particularly susceptible to a vicious-cycle positive feedback loop in which mild evidence of threat activates threat-response structures that bias the individual to interpret ambiguous evidence as threatening. This, then, further raises the threat arousal, further activates the threat-response structures, and so forth. The implications of this view for the treatment of PTSD and other anxiety disorders are discussed.

The effect of power on susceptibility to emotional contagion

Abstract This study explored two questions: Do people tend to display and experience other peoples emotions? If so, what impact does power have on peoples susceptibility to emotional contagion? We speculated that the powerless should pay more attention to their superiors (than their superiors pay to them) and should thus be especially likely to “catch” their superion emotions as well. College students, given the role of “teacher” (powerful person) or “learner” (powerless person), observed videotapes of another (fictitious) subject relating an emotional experience. They were asked what emotions they felt as they watched their partner describe the happiest and saddest event in his life. In addition, they were videotaped as they watched the tape. As predicted, clear evidence of emotional contagion was obtained in this controlled laboratory setting. However, a direct (rather than inverse) relation between power and emotional contagion was found. Powerful subjects were more likely to display their subordina...

Anger, impulsivity, and anger control in combat-related posttraumatic stress disorder.

Empirical evidence of a relationship between combat-related PTSD and increased anger is lacking. In this study, 24 veterans of the Vietnam War with posttraumatic stress disorder (PTSD) scored significantly higher on an Anger factor comprising multiple measures of anger than did comparison groups of 23 well-adjusted Vietnam combat veterans and 12 noncombat Vietnam-era veterans with psychiatric diagnoses. In contrast, the 3 groups did not differ significantly on orthogonal factors, one of which comprised cognitive impulsivity measures and the other of which reflected motor impulsivity. Changes in heart rate in response to provocation loaded positively on the Anger factor and negatively on the 2 Impulsivity factors. Concurrent depression and trait anxiety did not have an effect on level of anger in individuals with PTSD. These empirical findings support and extend the clinical evidence regarding PTSD and anger.

Measuring Exposure to Racism: Development and Validation of a Race-Related Stressor Scale (RRSS) for Asian American Vietnam Veterans

This article describes the development and validation of the Race-Related Stressor Scale (RRSS), a questionnaire that assesses exposure to race-related stressors in the military and war zone. Validated on a sample of 300 Asian American Vietnam veterans, the RRSS has high internal consistency and adequate temporal stability. Hierarchical regression analyses revealed that exposure to race-related stressors accounted for a significant proportion of the variance in posttraumatic stress disorder (PTSD) symptoms and general psychiatric symptoms, over and above (by 20% and 19%, respectively) that accounted for by combat exposure and military rank. The RRSS appears to be a psychometrically sound measure of exposure to race-related stressors for this population. Race-related stressors as measured by the RRSS appear to contribute uniquely and substantially to PTSD symptoms and generalized psychiatric distress.

Adverse Race-Related Events as a Risk Factor for Posttraumatic Stress Disorder in Asian American Vietnam Veterans

Few studies have explored the relationship between exposure to adverse race-related events and posttraumatic stress disorder (PTSD). This study examined whether adverse race-related events can give rise to symptoms that meet the criteria for a PTSD diagnosis as specified in the DSM-IV. Three hundred Asian American Vietnam veterans were administered a Mississippi Scale and a questionnaire that assessed exposure to adverse race-related events in the military and associated PTSD symptoms. A subsample was administered the Clinician-Administered PTSD Scale. A majority of the participants (77%) reported exposure to adverse race-related events. Depending on the number of events to which they were exposed, between 13% and 36% reported symptoms consistent with meeting full criteria for PTSD. Mississippi Scale scores increased significantly as a function of frequency of exposure to adverse race-related events. These results converge with the Clinician-Administered PTSD Scale findings to demonstrate that adverse race-related events can be traumatic and associated with PTSD. These findings support the construct and convergent validity of race-related PTSD.

Head injury and combat-related posttraumatic stress disorder.

Given the association of injury and posttraumatic stress disorder (PTSD), we examined whether head injury might be associated with increased frequency and severity of PTSD. Using a mail survey, we queried 143 male combat veterans with and without PTSD, who had previously participated in PTSD research in our laboratory, about their history of head injury. Respondents with a PTSD diagnosis were significantly more likely to report a history of head injury than those without. Patients with a history of head injury also reported more severe symptoms of PTSD compared with PTSD patients without head injury. The association of head injury and PTSD was not due to greater combat exposure in the head-injured group. Head injury is associated with a greater likelihood of developing combat-related PTSD and with more severe PTSD symptoms. This retrospective study did not address mechanisms that could account for this finding. The results indicate head injury should be systematically assessed by both nonpsychiatric and psychiatric physicians concerned with the psychological sequelae of exposure to victimizing experiences.

Posttraumatic reactions of hostages after an aircraft hijacking.

Studies of collective trauma and disasters emphasize the importance of psychiatric screening and evaluation after the event (Duckworth, 1986; Dyregrov, 1989; McFarlane, 1986; Salomon and Benbenishty, 1986). Hostages are often exposed to extreme psychological and physical violence (Allodi, 1994; Hill

Facial EMG responses to combat-related visual stimuli in veterans with and without posttraumatic stress disorder

Veterans with (n = 10) and without (n = 10) posttraumatic stress disorder (PTSD) participated in an exploratory study of facial reactivity to neutral slides and to slides depicting unpleasant combat-related material that were previously determined to be emotionally evocative. It was found that the zygomaticus major (cheek), masseter (jaw), and lateral frontalis (forehead) muscles were especially reactive to the combat slides in the veterans with PTSD, suggesting the importance of facial emotional expression in this disorder. The PTSD participants self-reports of overall distress paralleled these effects. However, autonomic reactivity did not reflect general arousal effects due to the visual stimuli, showing both the sensitivity of facial muscle assessment in this context and the need for further research on the relationship between stimulus modality and physiological trauma reactions. Additional directions for research in this area are discussed including efforts to correlate subjective and physiological reactions.