Unmasking Verbal Defensiveness: The Role of Psychological Threat in Sentence Completion Tests.

Shedding light on the validity of sentence completion test (SCT) verbal defensiveness as an index of defensive behavior, the current two-part study examined the relationship between psychological threat and verbal defensiveness among military security and mission-critical team candidates using SCTs. Our study showed that as the threatening nature of SCT stems increased, defensive responses also increased, substantiating the link between psychological threat and defensive behavior. In addition, expert ratings of stem content revealed moderately strong relationships with defensive responses across two different SCTs, irrespective of their structural characteristics. In contrast to previous studies using total verbal defensiveness scores, we examined specific defensive response types and their associations with stem threat ratings, finding that omissions, denial, and comments about the test were linked to stem threat levels. Lastly, our study extends the application of the SCT verbal defensiveness index beyond specialized personnel selection, finding no significant differences in verbal defensiveness based on gender or military status. Overall, these findings contribute to a comprehensive understanding of defensive behavior and its contextual variations.

Perspective: I believe what I remember, but it may not be true.

A growing number of research findings have challenged the conception that memory for traumatic events is highly accurate or even indelible in nature. Research involving soldiers indicates that realistic levels of high stress decrease the accuracy of eyewitness memory. In addition, recent findings from several studies show quite clearly that memories for stressful events - including those from combat trauma - are malleable and vulnerable to alteration by exposure to misinformation. Under high stress, our brains facilitate the formation of "gist" memories that allow us to avoid future dangers but which may not contain the detail and precision demanded by the judicial system. Although mental health professionals ought to play a role in educating the courts about mental illness and trauma, it is unwise for them to become advocates for the idea that traumatic memories are indelible, factual accounts of events.

Sex differences in cardiovascular and subjective stress reactions: prospective evidence in a realistic military setting.

Evidence points to heightened physiological arousal in response to acute stress exposure as both a prospective indicator and a core characteristic of posttraumatic stress disorder (PTSD). Because females may be at higher risk for PTSD development, it is important to evaluate sex differences in acute stress reactions. This study characterized sex differences in cardiovascular and subjective stress reactions among military survival trainees. One hundred and eighty-five military members (78% males) were studied before, during, and 24 h after stressful mock captivity. Cardiovascular (heart rate [HR], systolic blood pressure [SBP], diastolic blood pressure [DBP]) and dissociative states were measured at all three time points. Psychological impact of mock captivity was assessed during recovery. General linear modeling with repeated measures evaluated sex differences for each cardiovascular endpoint, and causal steps modeling was used to explore interrelationships among sex, cardiovascular reactions and psychological impact of mock captivity. Although females had lower SBP than males at all three time points, the difference was most pronounced at baseline and during stress. Accordingly, females showed greater residual elevation in SBP during recovery. Females had lower DBP at all three time points. In addition, females reported greater psychological impact of mock captivity than males. Exploratory causal steps modeling suggested that stress-induced HR may partially mediate the effect of sex on psychological impact of mock captivity. In conclusion, this study demonstrated sex-specific cardiovascular stress reactions in military personnel, along with greater psychological impact of stress exposure in females. This research may elucidate sex differences in PTSD development.

Efficacy of combining interview techniques in detecting deception related to bio-threat issues.

The purpose of this project was to assess the detecting deception efficacy of three well-validated "detecting deception" methods - i.e., forced choice testing (FCT), modified cognitive interviewing (MCI) and autobiographical implicit association testing (aIAT) - when applied to the issue of bio-threat. The detecting deception accuracies of FCT and MCI were 81% and 75%, respectively. Although the aIAT mean response times in block 5 differed significantly between deceptive and truthful persons, the classification accuracy was low. FCT alone reduced the group of 64 persons to 11 and detected 50% of the liars; the false positive rate was 9%. MCI alone reduced the group of 64 to 24 and detected 92% of the liars; the false positive rate was 54%. When FCT was paired with MCI, 75% of liars were detected and the false positive rate was 13%. Forced choice testing and MCI show promise as methods for detecting deception related to bio-threat under low-base-rate conditions. These methods took little time, enhanced the odds of detecting deceptive individuals and exhibited high positive likelihood ratios, suggesting that they have merit as screening tools. The aIAT required more time and was less accurate but may still serve as a useful screening tool.

Spontaneous and deliberate dissociative states in military personnel: are such states helpful?

This study explored distinctions between spontaneous and deliberate dissociative states in 335 military personnel exposed to stressful survival training. Participants completed the Clinician-Administered Dissociative States Scale (CADSS) after a stressful mock-captivity event. They were also asked to indicate whether the dissociative experiences just happened (i.e., spontaneous), or whether they chose to have them happen (i.e., deliberate); and whether they appraised the dissociative experience as helpful (i.e., facilitative) or hurtful (i.e., debilitative) to their ability to cope with the stressful event. A majority (95.4%) endorsed dissociative states during stress. More than half (57.4%) described dissociative experiences as spontaneous, 13.0% as deliberate, and 29.5% endorsed neither. In Special Forces soldiers only, those who endorsed facilitative dissociation exhibited higher total CADSS scores than those who endorsed debilitative dissociation. Seventy-three percent of spontaneous dissociators described the experience as debilitative to coping with stress; conversely, 76% of deliberate dissociators said these experiences facilitated coping with stress. Individuals with prior trauma exposure tended to appraise dissociative states as more debilitative to coping. This research may enhance the fidelity of studies of dissociation constructs and may offer pivot points for prevention and treatment of stress-related disorders.

Baseline burnout symptoms predict visuospatial executive function during survival school training in special operations military personnel.

Burnout symptoms, which are characterized by exhaustion, cynicism, and a reduced sense of professional efficacy, may deleteriously affect cognitive function in military personnel. A total of 32 U.S. Military Special Operations personnel enrolled in Survival School completed measures of trauma history, dissociation, and burnout before training. They then completed the Groton Maze Learning Test (GMLT), a neuropsychological measure of integrative visuospatial executive function during three field-based phases of Survival School-enemy evasion, captivity/interrogation, and escape/release from captivity. Lower pre-training perceptions of professional efficacy were associated with reduced executive function during all of the field-based phases of Survival School, even after adjustment for years of education, cynicism, and baseline GMLT scores. Magnitudes of decrements in executive function in Marines with low efficacy relative to those with high efficacy increased as training progressed and ranged from .58 during enemy evasion to .99 during escape/release from captivity. Pre-training perceptions of burnout may predict visuospatial executive function during naturalistic training-related stress in military personnel. Assessment of burnout symptoms, particularly perceptions of professional efficacy, may help identify military personnel at risk for stress-related executive dysfunction.

Effect of carbohydrate administration on recovery from stress-induced deficits in cognitive function: a double-blind, placebo-controlled study of soldiers exposed to survival school stress.

OBJECTIVE: The goal of this project was to evaluate the effects of energy supplementation, as liquid carbohydrate (CHO), on facilitating recovery of cognitive function in soldiers who have been exposed to sustained psychological and physical stress during Survival School Training. PROJECT DESIGN: A double-blind, placebo-controlled design was used. Healthy, male volunteers attending survival training were recruited for participation in the study. At the conclusion of the mock captivity phase of survival training and before a recovery night of sleep, subjects participated in cognitive testing. After this, subjects were randomly assigned to one of three treatment groups. Subjects received either a 6% CHO (35.1 kJ/kg), 12% CHO (70.2 kJ/kg), or placebo beverage in four isovolemic doses. In the morning of the following day, all subjects participated in a second assessment of cognitive functioning. RESULTS: Compared to subjects who received placebo, those who received supplemental CHO beverages exhibited significantly improved performance on a complex cognitive task (i.e., Stroop Test) involving concentration effectiveness associated with selective attention and response inhibition. No differences were observed on a variety of cognitive tasks of lesser complexity. DISCUSSION: These data suggest nutritional interventions enhance the rapid recovery of complex cognitive functions impaired by exposure to significant or sustained stressful conditions. In addition to enhancing speed of recovery of function between operational intervals, the current data suggest that dietary supplement strategies may hold promise for enhancing field performance and a capacity to assist in sustaining operations by military personnel over time.

Changes in mood, fatigue, sleep, cognitive performance and stress hormones among instructors conducting stressful military captivity survival training.

Numerous studies have examined the effects of captivity survival training on psychological and physiological function in trainees. In the present study we shifted the focus to instructors, and measured the effects that the delivery of training exerts on their levels of stress and performance. Because instructors are called upon to perform difficult duties (e.g., mock interrogations) under extreme conditions, we hypothesized that significant increases in psychological and physiological indices of stress would occur due to training. In addition, as part of their job tasking, the instructors conducted courses in consecutive weeks. This offered a unique and ecologically valid opportunity to assess carryover of stress from one week to the next. We hypothesized stress levels would be higher in the second than the first week of training. Our first hypothesis was supported: Delivering training was associated with impairments in mood, fatigue, and sleep, as well as a reduction in the ratio of testosterone/cortisol level in blood. Our second hypothesis was largely not supported as a 3-day break separating consecutive courses appeared sufficient for restoring psychological and physiological function. Our results demonstrate that although the delivery of training exerts negative effects on instructors' levels of stress, the 3-day recovery period separating consecutive courses is sufficient to return psychological and physiological function to baseline levels.

Cohesion, burnout, and past trauma in tri-service medical and support personnel.

Past research suggests that the negative consequences related to exposure to traumatic events and injury may impact cohesive work relationships. Additionally, trauma and low cohesive relationships independently predict poorer psychological and physical health in service members. The objective of the present study was to examine the interrelationships between exposure to traumatic events, burnout, and cohesion among tri-service medical and support staff. Surveys were administered to 253 U.S. Army, Army Reserve Units, U.S. Air Force, and U.S. Navy personnel upon arrival in Hawaii for participation in a stressful, 2-week training exercise. Results showed that history of trauma was correlated with poorer view of officers and higher levels on two components of burnout. We discuss how findings can apply to prevention and early intervention efforts.

Accuracy of eyewitness identification is significantly associated with performance on a standardized test of face recognition.

OBJECTIVES: This study assessed the relationship between Eyewitness Accuracy regarding a person met under conditions of high stress and performance on a standardized, neutral test of memory for human faces. METHOD: Fifty-three U.S. Army personnel were exposed to interrogation stress. Forty-eight hours later, participants were administered the Weschler Face Test and then asked to identify the one interrogator who they had encountered 48 h earlier. RESULTS: A significant positive relationship was observed between performance on the Weschler Face Test and performance on the Eyewitness task. Inaccurate eyewitnesses exhibited more False Negative errors when performing the Weschler Face Test. DISCUSSION: Trait ability to remember human faces may be related to how accurately people recall faces that are associated with highly emotional circumstances. Detection probability methods, such as ROC curve analyses, may be of assistance to forensic examiners, the police, and the courts, when assessing the probability that eyewitness evidence is accurate.

Psychological Perspectives on Interrogation.

Proponents of "enhanced interrogation techniques" in the United States have claimed that such methods are necessary for obtaining information from uncooperative terrorism subjects. In the present article, we offer an informed, academic perspective on such claims. Psychological theory and research shows that harsh interrogation methods are ineffective. First, they are likely to increase resistance by the subject rather than facilitate cooperation. Second, the threatening and adversarial nature of harsh interrogation is often inimical to the goal of facilitating the retrieval of information from memory and therefore reduces the likelihood that a subject will provide reports that are extensive, detailed, and accurate. Third, harsh interrogation methods make lie detection difficult. Analyzing speech content and eliciting verifiable details are the most reliable cues to assessing credibility; however, to elicit such cues subjects must be encouraged to provide extensive narratives, something that does not occur in harsh interrogations. Evidence is accumulating for the effectiveness of rapport-based information-gathering approaches as an alternative to harsh interrogations. Such approaches promote cooperation, enhance recall of relevant and reliable information, and facilitate assessments of credibility. Given the available evidence that torture is ineffective, why might some laypersons, policymakers, and interrogation personnel support the use of torture? We conclude our review by offering a psychological perspective on this important question.

The effects of captivity survival training on mood, dissociation, PTSD symptoms, cognitive performance and stress hormones.

In the Canadian Armed Forces (CAF), Conduct After Capture (CAC) training is a 4-day captivity survival course during which soldiers are exposed to increasing stress, and evaluated on their ability to accomplish military objectives. We hypothesized that: (a) compared to baseline, CAC training would cause significant, reversible perturbations in measures of psychological functioning and serum and salivary stress hormone levels relevant to models of stress hardiness and vulnerability; and (b) deviations from baseline would be maximal at the time point of most intense stress during training. CAF personnel were assessed at baseline, twice during training (immediately prior to a less challenging interrogation role-play scenario and again following another much more intense interrogation role-play scenario), and after completion of training. At each occasion, mood, fatigue, dissociation, PTSD symptoms, short-term and working memory, and salivary cortisol and dehydroepiandrosterone (DHEA) were assessed. As predicted, scores on all measures were degraded during CAC but recovered after completion of training, and almost all measures were most degraded at the more intense interrogation role-play scenario. Unexpectedly, memory performance was unaffected by training, suggesting that a short duration of intense stress might be insufficient for degrading it. Another unexpected finding was that mood assessed prior to training predicted successful completion of training, which bears important practical implications for increasing the success rate of training in similar environments. These results demonstrate that despite its relative brevity, CAC training nevertheless induces significant but reversible effects on psychological and physiological function-necessary preconditions for stress inoculation training.

Stress-induced deficits in working memory and visuo-constructive abilities in Special Operations soldiers.

BACKGROUND: Pre-clinical and clinical studies have shown acute stress may impair working memory and visuo-spatial ability. This study was designed to clarify the nature of stress-induced cognitive deficits in soldiers and how such deficits may contribute to operational or battlefield errors. METHODS: One hundred eighty-four Special Operations warfighters enrolled in Survival School completed pre-stress measures of dissociation and trauma exposure. Subjects were randomized to one of three assessment groups (Pre-stress, Stress, Post-stress) and were administered the Rey Ostereith Complex Figure (ROCF). All subjects completed post-stress measures of dissociation. RESULTS: ROCF copy and recall were normal in the Pre- and Post-stress groups. ROCF copy and recall were significantly impaired in the Stress Group. Stress group ROCF copy performance was piecemeal, and ROCF recall was impaired. Symptoms of dissociation were negatively associated with ROCF recall in the Stress group. Baseline dissociation and history of traumatic stress predicted cognitive impairment during stress. CONCLUSIONS: Stress exposure impaired visuo-spatial capacity and working memory. In rats, monkeys, and humans, high dopamine and NE turnover in the PFC induce deficits in cognition and spatial working memory. Improved understanding of stress-induced cognitive deficits may assist in identification of soldiers at risk and lead to the development of better countermeasures.

Dissociation, hardiness, and performance in military cadets participating in survival training.

The present study examined the relationship between peritraumatic dissociation, hardiness, and military performance in Norwegian Navy officer cadets (N = 80) after a simulated prisoner of war (POW) exercise. The cadets reported symptoms of peritraumatic amnesia, depersonalization, and derealization in response to a mild stress experience (time point 1) and exhibited a significant increase in such symptoms when subsequently exposed to a highly stressful experience of being placed in a mock POW camp (time point 2). Symptoms of peritraumatic dissociation were significantly and negatively related to performance, and predicted between 16 and 26% of the variance between subjects. A subscale of the personality hardiness measure (i.e., the subdimension of challenge) was negatively associated with peritraumatic dissociation in response to both the mild stress situation and the more stressful POW exercise in study subjects. Hardiness was not significantly associated with military performance scores. The present data indicate that individual differences in attribution style and in a propensity to dissociate significantly affect military performance during exposure to high stress situations.

How Personality Affects Vulnerability among Israelis and Palestinians following the 2009 Gaza Conflict.

Can the onset of PTSD symptoms and depression be predicted by personality factors and thought control strategies? A logical explanation for the different mental health outcomes of individuals exposed to trauma would seem to be personality factors and thought control strategies. Trauma exposure is necessary but not sufficient for the development of PTSD. To this end, we assess the role of personality traits and coping styles in PTSD vulnerability among Israeli and Palestinian students amid conflict. We also determine whether gender and exposure level to trauma impact the likelihood of the onset of PTSD symptoms. Five questionnaires assess previous trauma, PTSD symptoms, demographics, personality factors and thought control strategies, which are analyzed using path analysis. Findings show that the importance of personality factors and thought control strategies in predicting vulnerability increases in the face of political violence: the higher stress, the more important the roles of personality and thought control strategies. Thought control strategies associated with introverted and less emotionally stable personality-types correlate positively with higher levels of PTSD symptoms and depression, particularly among Palestinians. By extension, because mental health is key to reducing violence in the region, PTSD reduction in conflict zones warrants rethinking.

Severe decrements in cognition function and mood induced by sleep loss, heat, dehydration, and undernutrition during simulated combat.

BACKGROUND: Military exercises generate high levels of stress to simulate combat, providing a unique opportunity to examine cognitive and physiologic responses of normal humans to acute stress. METHODS: Cognitive and physiologic markers of stress were evaluated before, during, and after an intense training exercise conducted for 53 hours in the heat. Cognitive performance, mood, physical activity, sleep, body composition, hydration, and saliva cortisol, testosterone, and melatonin were assessed. Volunteers were 31 male U.S. Army officers from an elite unit, aged 31.6 +/- .4 years. RESULTS: Wrist activity monitors documented that soldiers slept only 3.0 +/- .3 hours during the exercise and were active throughout. Volunteers lost 4.1 +/- .2 kg (p < .001) of weight, predominately water (3.1 +/- .3 L) (p < .001). Substantial degradation in cognitive function, assessed with computerized tests, occurred. Vigilance, reaction time, attention, memory, and reasoning were impaired (p < .001). Mood, including vigor (p < .001), fatigue (p < .001), confusion (p < .001), depression (p < .001), and tension (p < .002), assessed by questionnaire, deteriorated. The highest cortisol and testosterone levels were observed before the exercise. CONCLUSIONS: This study quantifies the overwhelmingly adverse impact of multiple stressors on cognitive performance, mood, and physiologic parameters, during a continuous but brief military exercise conducted by highly motivated, well-trained officers.

Relationships among plasma dehydroepiandrosterone sulfate and cortisol levels, symptoms of dissociation, and objective performance in humans exposed to acute stress.

CONTEXT: Recently, a growing body of research has provided evidence that dehydroepiandrosterone sulfate (DHEA-S) is involved in an organism's response to stress and that it may provide beneficial behavioral and neurotrophic effects. OBJECTIVE: To investigate plasma DHEA-S and cortisol levels, psychological symptoms of dissociation, and military performance. DESIGN: Prospective study. SETTING AND PARTICIPANTS: Twenty-five healthy subjects enrolled in military survival school. RESULTS: The DHEA-S-cortisol ratios during stress were significantly higher in subjects who reported fewer symptoms of dissociation and exhibited superior military performance. CONCLUSIONS: These data provide prospective, empirical evidence that the DHEA-S level is increased by acute stress in healthy humans and that the DHEA-S-cortisol ratio may index the degree to which an individual is buffered against the negative effects of stress.

Smaller head of the hippocampus in Gulf War-related posttraumatic stress disorder.

Reductions in hippocampal volume and impairment in short-term verbal memory have been reported in Vietnam combat veterans with posttraumatic stress disorder (PTSD) and in women with abuse-related PTSD. The present investigation evaluated hippocampal volume and memory in Gulf War veterans. This research is timely given the ongoing war in Iraq and the anticipated high rates of PTSD among returning combat soldiers. Fourteen veterans with PTSD related to traumatic experiences during the Gulf War (1990-1991), 23 deployed veterans without PTSD, 22 non-deployed reservists and 29 healthy civilians were studied. Volumes of the hippocampus, temporal lobe, and whole brain were measured on coronal MRI scans, and hippocampal mediated memory function was evaluated. The head of the hippocampus was the only subregion that was significantly smaller in Gulf War veterans with PTSD than in healthy civilians. Deployed veterans with PTSD, deployed veterans without PTSD, and non-deployed reservists had significantly smaller whole hippocampal volume and lower scores on immediate and delayed verbal and visual retrieval compared with healthy civilians.

The fog of war: decrements in cognitive performance and mood associated with combat-like stress.

INTRODUCTION: Anecdotal reports from military conflicts suggest cognitive performance and mood are severely degraded by the stress of combat. However, little objective information is available to confirm these observations. METHODS: Our laboratory had several unique opportunities to study cognitive function in warfighters engaged in exercises designed to simulate the stress of combat. These studies were conducted in different environments with two different types of military volunteers. In one study, subjects were officers, with an average 9 yr of military service, who were members of an elite U.S. Army unit, the Rangers. In the other study, participants were younger, mostly enlisted, trainees with only 3 yr of military experience on average, in training to determine if they would qualify for an elite U.S. Navy unit, the SEALS. We administered a variety of identical, computer-based cognitive tests to both groups. RESULTS: In both groups, during stressful combat-like training, every aspect of cognitive function assessed was severely degraded compared with baseline, pre-stress performance. Relatively simple cognitive functions such as reaction time and vigilance were significantly impaired, as were more complex functions, including memory and logical reasoning. DISCUSSION: The deficits observed were greater than those typically produced by alcohol intoxication, treatment with sedating drugs, or clinical hypoglycemia. Undoubtedly, such decrements would severely degrade operational effectiveness. Furthermore, it is likely such cognitive decrements would be greater during actual combat. War planners, doctrine developers, and warfighters, especially leaders, need to be aware that combat stress will result in extensive and severe deficits in cognitive performance.

Toward early pharmacological posttraumatic stress intervention.

In the acute aftermath of exposure to extreme stress, nearly all trauma survivors experience one or more transient symptoms of stress. In the short run, these symptoms may serve an adaptive role and generally remit; in some cases, however, acute stress-related symptoms do not diminish and instead evolve into posttraumatic stress disorder (PTSD). At present it is not clear when and with whom to intervene. On one hand, it is possible that some responses, such as early intrusive memories, effectively recruit support from others and facilitate the psychological processing of trauma; on the other hand, failing to intervene clinically with a recently traumatized individual may permit the subsequent development of PTSD. In this review, we focus on potential pharmacologic interventions aimed at treating early symptoms of extreme arousal or dissociation with the hope of possibly preventing PTSD. To date there is almost no empirical data on effective pharmacologic interventions in the immediate aftermath of extreme psychological trauma. As a result, much of what is discussed in this review is speculative in nature