Attention, learning, and memory performances and intellectual resources in Vietnam veterans: PTSD and no disorder comparisons

Neuropsychological measurement of inhibitory control in posttraumatic stress disorder: An exploratory antisaccade paradigm

OBJECTIVE

The aim of the study was to uncover inhibitory control dynamics and assess antisaccade eye-tracking tasks for relevance in a veteran posttraumatic stress disorder (PTSD) population.

METHOD

Participants were 36 veterans enrolled at the Washington DC Veterans Affairs Medical Center. The groups (PTSD diagnosed vs. controls) did not vary between age and sex. Participants completed a testing battery of clinical neuropsychological measures and two different eye-tracking conditions, one that utilized face stimuli and one with standard shape stimuli, which test pro- (PS) and antisaccade (AS) eye movements.

RESULTS

Veterans with PTSD, t(33) = 2.2, p = .04, took longer to respond than controls in the standard condition AS. In the face condition, a group by task interaction was seen with increased latency for PTSD veterans in the AS versus PS task, F(3, 33) = 3.99, p = .05, with a large overall effect (Hedges' g = 1.18, p < .001) compared to controls. After controlling for depression, analyses suggested that only the face condition AS task significantly predicted dimensions of PTSD symptomology measured by the Clinician Administered PTSD Scale (CAPS) for veterans with PTSD.

CONCLUSIONS

This is the first study to extend AS findings to PTSD and suggests a specific capability to measure inhibitory control using eye-tracking technology. We discuss the notion that reduced capacity to regulate facial-related processing affects cognitive and attentional control networks of PTSD patients, potentially representing a core cognitive deficit.

Effects of traumatic brain injury and posttraumatic stress disorder on development of Alzheimer's disease in Vietnam Veterans using the Alzheimer's Disease Neuroimaging Initiative: Preliminary Report

INTRODUCTION

Traumatic brain injury (TBI) and posttraumatic stress disorder (PTSD) have previously been reported to be associated with increased risk of Alzheimer's disease (AD). We are using biomarkers to study Vietnam Veterans with/without mild cognitive impairment with a history of at least one TBI and/or ongoing PTSD to determine whether these contribute to the development of AD.

METHODS

Potential subjects identified by Veterans Administration records underwent an initial telephone screen. Consented subjects underwent clinical evaluation, lumbar puncture, structural MRI and amyloid PET scans.

RESULTS

We observed worse cognitive functioning in PTSD and TBI + PTSD groups, worse global cognitive functioning in the PTSD group, lower superior parietal volume in the TBI + PTSD group, and lower amyloid positivity in the PTSD group, but not the TBI group compared to controls without TBI/PTSD. Medial temporal lobe atrophy was not increased in the PTSD and/or TBI groups.

DISCUSSION

Preliminary results do not indicate that TBI or PTSD increase the risk for AD measured by amyloid PET. Additional recruitment, longitudinal follow-up, and tau PET scans will provide more information in the future.

Association of Fluid Intelligence and Psychiatric Disorders in a Population-Representative Sample of US Adolescents

IMPORTANCE

Despite long-standing interest in the association of psychiatric disorders with intelligence, few population-based studies of psychiatric disorders have assessed intelligence.

OBJECTIVE

To investigate the association of fluid intelligence with past-year and lifetime psychiatric disorders, disorder age at onset, and disorder severity in a nationally representative sample of US adolescents.

DESIGN, SETTING, AND PARTICIPANTS

National sample of adolescents ascertained from schools and households from the National Comorbidity Survey Replication-Adolescent Supplement, collected 2001 through 2004. Face-to-face household interviews with adolescents and questionnaires from parents were obtained. The data were analyzed from February to December 2016. DSM-IV mental disorders were assessed with the World Health Organization Composite International Diagnostic Interview, and included a broad range of fear, distress, behavior, substance use, and other disorders. Disorder severity was measured with the Sheehan Disability Scale.

MAIN OUTCOMES AND MEASURES

Fluid IQ measured with the Kaufman Brief Intelligence Test, normed within the sample by 6-month age groups.

RESULTS

The sample included 10 073 adolescents (mean [SD] age, 15.2 [1.50] years; 49.0% female) with valid data on fluid intelligence. Lower mean (SE) IQ was observed among adolescents with past-year bipolar disorder (94.2 [1.69]; P = .004), attention-deficit/hyperactivity disorder (96.3 [0.91]; P = .002), oppositional defiant disorder (97.3 [0.66]; P = .007), conduct disorder (97.1 [0.82]; P = .02), substance use disorders (alcohol abuse, 96.5 [0.67]; P < .001; drug abuse, 97.6 [0.64]; P = .02), and specific phobia (97.1 [0.39]; P = .001) after adjustment for a wide range of potential confounders. Intelligence was not associated with posttraumatic stress disorder, eating disorders, and anxiety disorders other than specific phobia, and was positively associated with past-year major depression (mean [SE], 100 [0.5]; P = .01). Associations of fluid intelligence with lifetime disorders that had remitted were attenuated compared with past-year disorders, with the exception of separation anxiety disorder. Multiple past-year disorders had a larger proportion of adolescents less than 1 SD below the mean IQ range than those without a disorder. Across disorders, higher disorder severity was associated with lower fluid intelligence. For example, among adolescents with specific phobia, those with severe disorder had a mean (SE) of 4.4 (0.72) points lower IQ than those without severe disorder (P < .001), and those with alcohol abuse had a mean (SE) of 5.6 (1.2) points lower IQ than those without severe disorder (P < .001).

CONCLUSIONS AND RELEVANCE

Numerous psychiatric disorders were associated with reductions in fluid intelligence; associations were generally small in magnitude. Stronger associations of current than past disorders with intelligence suggest that active symptoms of psychiatric disorders interfere with cognitive functioning. Early identification and treatment of children with mental disorders in school settings is critical to promote academic achievement and long-term success.

Development, Administration, and Structural Validity of a Brief, Computerized Neurocognitive Battery: Results From the Army Study to Assess Risk and Resilience in Servicemembers

The Army Study to Assess Risk and Resilience in Servicemembers (Army STARRS) is a research project aimed at identifying risk and protective factors for suicide and related mental health outcomes among Army Soldiers. The New Soldier Study component of Army STARRS included the assessment of a range of cognitive- and emotion-processing domains linked to brain systems related to suicidal behavior including posttraumatic stress disorder, mood disorders, substance use disorders, and impulsivity. We describe the design and application of the Army STARRS neurocognitive test battery to a sample of 56,824 soldiers. We investigate its structural and concurrent validity through factor analysis and correlation of scores with demographics. We conclude that, in addition to being composed of previously well-validated measures, the Army STARRS neurocognitive battery as a whole demonstrates good psychometric properties. Correlations of scores with age and sex differences mostly replicate previously published findings, highlighting moderate to large effect sizes even within this restricted age range. Factor structures of scores conform to theoretical expectations. This neurocognitive battery provides a brief, valid measurement of neurocognition that may be helpful in predicting mental health and military performance. These measures can be integrated with neuroimaging to offer a powerful tool for assessing neurocognition in Servicemembers.

Dissociation between working memory performance and proactive interference control in post-traumatic stress disorder

Deficits in working memory (WM) and cognitive control processes have been reported in post-traumatic stress disorder (PTSD), in addition to clinical symptoms such as hypervigilance, re-experiencing, and avoidance of trauma reminders. Given the uncontrollable nature of intrusive memories, an important question is whether PTSD is associated with altered control of interference in WM. Some studies also suggest that episodic memory shows a material-specific dissociation in PTSD, with greater impairments in verbal memory and relative sparing of nonverbal memory. It is unclear whether this dissociation applies to WM, as no studies have used identical task parameters across material. Here we tested 29 combat Veterans with PTSD and 29 age-matched control Veterans on a recent probes WM task with words and visual patterns in separate blocks. Participants studied four-item sets, followed by a probe stimulus that had been presented in the previous set (recent probe) or not (nonrecent probe). Participants with PTSD made more errors than controls, and this decrement was similar for verbal and visual stimuli. Proactive interference from items recently presented, but no longer relevant, was not significantly different in the PTSD group and showed no relationship to re-experiencing symptom severity. These results demonstrate that PTSD is not reliably associated with increased intrusions of irrelevant representations into WM when non-emotional stimuli are used. Future studies that use trauma-related material may provide insight into the flashbacks and intrusive thoughts that plague those with PTSD.

A meta-analysis of the relationship between symptom severity of Posttraumatic Stress Disorder and executive function

INTRODUCTION

Some studies of Posttraumatic Stress Disorder (PTSD) find executive dysfunction, whereas others do not. We meta-analytically examined the association between executive function and PTSD and used meta-regression to examine the potential moderating effect of PTSD severity on executive function.

METHODS

We conducted a meta-analysis according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We identified published peer-reviewed articles containing measures of executive function and PTSD symptom severity in subjects with PTSD compared to trauma-unexposed controls or trauma-exposed controls without PTSD, or both. We calculated an effect size for each study containing at least one measure of executive function and PTSD symptom severity.

RESULTS

PTSD subjects for whom the Clinician-Administered PTSD Scale (CAPS) score was available had worse executive function compared to both trauma-unexposed controls (g = 0.464, p < .001) and to trauma-exposed controls without PTSD (g = 0.414, p = .001), as did PTSD subjects for whom the Mississippi Scale for Combat-Related PTSD (M-PTSD) score was available (g = 0.390, p < .001). Neither CAPS nor M-PTSD scores significantly moderated the effect size of executive function.

CONCLUSIONS

PTSD is associated with executive dysfunction, but this association was not moderated by PTSD symptom severity, suggesting that once PTSD occurs, executive dysfunction may occur regardless of PTSD severity.

War and remembrance: Combat exposure in young adulthood and memory function sixty years later

OBJECTIVE

Identifying adaptive ways to cope with extreme stress is essential to promoting long-term health. Memory systems are highly sensitive to stress, and combat exposure during war has been shown to have deleterious effects on cognitive processes, such as memory, decades later. No studies have examined coping styles used by combat veterans and associations with later-life cognitive functioning. Defenses are coping mechanisms that manage difficult memories and feelings, with some more closely related to memory processes (e.g., suppression, repression). Utilizing a longitudinal database, we assessed how reliance on certain defense mechanisms after World War II combat exposure could affect cognitive health 60years later.

METHOD

Data spanning 75years were available on 71 men who had post-war assessment of combat exposure, defense mechanism ratings (ages 19-50), and late-life neuropsychological testing. Interaction models of combat exposure with defenses predicting late-life memory were examined.

RESULTS

In bivariate analyses, greater reliance on suppression correlated with worse memory performance (r=-0.30, p=.01), but greater reliance on repression did not. Greater reliance on suppression strengthened the link between combat exposure and worse memory in late life (R²=0.24, p<.001). In contrast, greater reliance on repression attenuated the link between combat exposure and poorer late-life memory (R²=0.19, p<.001).

CONCLUSIONS

Results suggest that coping styles may affect the relationship between early-adult stress and late-life cognition. Findings highlight the importance of understanding how coping styles may impact cognitive functioning as people move through adult life.

PTSD symptom severity relates to cognitive and psycho-social dysfunctioning - a study with Congolese refugees in Uganda

Background: In the ongoing conflict in the Democratic Republic of the Congo (DRC), civilians have been heavily exposed to traumatic stressors. Traumatizing experiences cumulatively heighten the risk for trauma-related disorders, and with it affect cognitive and psycho-social functioning. Objectives: We aimed at investigating the association between trauma-related disorders and cognitive and psycho-social functioning and hypothesized that PTSD symptom severity would negatively correlate with executive functioning, working memory and psycho-social functioning in everyday life. Method: In total, 323 Congolese refugees (mean age: 31.3 years) who arrived in the Ugandan Nakivale refugee settlement after January 2012 were assessed regarding their exposure to traumatic events, PTSD symptom severity (posttraumatic symptom scale interview), executive functioning (Tower of London), working memory performance (Corsi block tapping task) and psycho-social dysfunctioning (Luo functioning scale). Results: Hierarchical regression analyses indicated a significant negative association between PTSD symptom severity and working memory (β = -0.32, p < 0.001), as well as executive functions (β = -0.19, p = 0.003). Furthermore, the impairment of psycho-social functioning in everyday life was positively related with PTSD symptom severity (β = 0.70, p < 0.001), and negatively with executive functioning (β = -0.15, p = 0.003). However, working memory performance was not significantly related to psycho-social dysfunctioning (β = 0.09, p > 0.05). Conclusion: Trauma survivors not only suffer from the core PTSD symptoms but also from impaired cognitive functioning. PTSD symptom severity seems furthermore to be related to impaired psycho-social functioning. Our findings suggest that trauma-related mental health problems may heighten the risk for poverty and lack of prospect and further aggravate the consequences of war and conflict.

Elevated rates of memory impairment in military service-members and veterans with posttraumatic stress disorder

INTRODUCTION

Studies investigating the neurocognitive effects of posttraumatic stress disorder (PTSD) routinely find "deficits" in various cognitive domains. However, the rate of cognitive impairment in individuals with PTSD remains unclear, as studies have focused on null hypothesis testing (NHT) and inferring patterns of impairment rather than empirically determining the rate of cognitive impairment in this sample.

METHOD

This study examined rates of cognitive impairment using a domain-specific approach in non-treatment-seeking Operation Enduring Freedom/Operation Iraqi Freedom/Operation New Dawn service members and veterans with (n = 92) and without (n = 79) PTSD and without substance abuse/dependence who passed a performance validity measure and were matched on age, education, estimated IQ, and ethnicity. Chi-square analyses were used to compare the rate of cognitive impairment across groups based on normative scores using three cutoffs (-1, -1.5, and -2 SDs). NHT was also used to compare performances across groups.

RESULTS

Individuals with PTSD showed higher rates of impairment in memory (-1-SD cutoff) than controls, but equivalent rates of impairment in attention, processing speed, and executive functioning; no significant differences were found on NHT. Impairment in any domain was also more prevalent in PTSD (-1-, -1.5-, and -2-SD cutoffs). No differences were found on NHT or rates of impairment in individuals with PTSD with (n = 34) and without (n = 58) depression.

CONCLUSIONS

Patients with PTSD were more likely to meet criteria for memory impairment and to show impairment in any domain than controls. Patients with PTSD and comorbid depression were no more likely to be impaired in any cognitive domain or to have lower scores on individual cognitive tasks than patients with PTSD alone. Clinicians noting cognitive impairment in individuals with PTSD should exercise caution before ascribing that impairment to another etiology if deficits are limited to memory.

Exposure to childhood trauma is associated with altered n-back activation and performance in healthy adults: implications for a commonly used working memory task

Previous research suggests that a history of early life stress (ELS) impacts working memory (WM) in adulthood. Despite the widespread use of WM paradigms, few studies have evaluated whether ELS exposure, in the absence of psychiatric illness, also impacts WM-associated brain activity in ways that might improve sensitivity to these ELS effects or provide insights into the mechanisms of these effects. This study evaluated whether ELS affects WM behavioral performance and task-associated activity by acquiring 3T functional images from 27 medication-free healthy adults (14 with ELS) during an N-back WM task that included 0- and 2-back components. Whole brain voxel-wise analysis was performed to evaluate WM activation, followed by region of interest analyses to evaluate relationships between activation and clinical variables. ELS was associated with poorer accuracy during the 2-back (79% ± 19 vs. 92% ± 9, p = 0.049); accuracy and response time otherwise did not differ between groups. During the 0-back, ELS participants demonstrated increased activation in the superior temporal gyrus/insula, left inferior parietal lobule (IPL) (both corrected p < 0.001), and middle temporal and parahippocampal gyrus (MTG/PHG)(corrected p < 0.010). During the 2-back, ELS was associated with greater activation in the IPL, MTG/PHG and inferior frontal gyrus (corrected p < 0.001), with a trend towards precuneus activation (p = 0.080). These findings support previous research showing that ELS is associated with impaired neurobehavioral performance and changes in brain activation, suggesting recruitment of additional cognitive resources during WM in ELS. Based on these findings, ELS screening in future WM imaging studies appears warranted.

The Neuropsychological Profile of Comorbid Post-Traumatic Stress Disorder in Adult ADHD

OBJECTIVE

ADHD and post-traumatic stress disorder (PTSD) are often comorbid yet despite the increased comorbidity between the two disorders, to our knowledge, no data have been published regarding the neuropsychological profile of adults with comorbid ADHD and PTSD. Likewise, previous empirical studies of the neuropsychology of PTSD did not control for ADHD status. We sought to fill this gap in the literature and to assess the extent to which neuropsychological test performance predicted psychosocial functioning, and perceived quality of life.

METHOD

Participants were 201 adults with ADHD attending an outpatient mental health clinic between 1998 and 2003 and 123 controls without ADHD. Participants completed a large battery of self-report measures and psychological tests. Diagnoses were made using data obtained from structured psychiatric interviews (i.e., Structured Clinical Interview for DSM-IV, Schedule for Affective Disorders and Schizophrenia for School-Age Children Epidemiologic Version).

RESULTS

Differences emerged between control participants and participants with ADHD on multiple neuropsychological tests. Across all tests, control participants outperformed participants with ADHD. Differences between the two ADHD groups emerged on seven psychological subtests including multiple Wechsler Adult Intelligence Scale-Third edition and Rey-Osterrieth Complex Figure Test measures. These test differences did not account for self-reported quality of life differences between groups.

CONCLUSION

The comorbidity with PTSD in adults with ADHD is associated with weaker cognitive performance on several tasks that appear related to spatial/perceptual abilities and fluency. Neuropsychological test performances may share variance with the quality of life variables yet are not mediators of the quality of life ratings.

Executive Dysfunctions: The Role in Attention Deficit Hyperactivity and Post-traumatic Stress Neuropsychiatric Disorders

Executive functions (EFs) is an umbrella term for various cognitive processes controlled by a complex neural activity, which allow the production of different types of behaviors seeking to achieve specific objectives, one of them being inhibitory control. There is a wide consensus that clinical and behavioral alterations associated with EF, such as inhibitory control, are present in various neuropsychiatric disorders. This paper reviews the research literature on the relationship between executive dysfunction, frontal-subcortical neural circuit changes, and the psychopathological processes associated with attention deficit hyperactivity disorder (ADHD) and post-traumatic stress disorder (PTSD). A revision on the role of frontal-subcortical neural circuits and their presumable abnormal functioning and the high frequency of neuropsychiatric symptoms could explain the difficulties with putting effector mechanisms into action, giving individuals the necessary tools to act efficiently in their environment. Although, neuronal substrate data about ADHD and PTSD has been reported in the literature, it is isolated. Therefore, this review highlights the overlapping of neural substrates in the symptomatology of ADHD and PTSD disorders concerning EFs, especially in the inhibitory component. Thus, the changes related to impaired EF that accompany disorders like ADHD and PTSD could be explained by disturbances that have a direct or indirect impact on the functioning of these loops. Initially, the theoretical model of EF according to current neuropsychology will be presented, focusing on the inhibitory component. In a second stage, this component will be analyzed for each of the disorders of interest, considering the clinical aspects, the etiology and the neurobiological basis. Additionally, commonalities between the two neuropsychiatric conditions will be taken into consideration from the perspectives of cognitive and emotional inhibition. Finally, the implications and future prospects for research and interventions in the area will be outlined, with the intention of contributing scientific reference information that encompasses the knowledge and understanding of executive dysfunction and its relationship with these treated disorders.

Prospective Memory in Posttraumatic Stress Disorder

OBJECTIVES

Neuropsychological studies of posttraumatic stress disorder (PTSD) have revealed deficits in attention/working memory, processing speed, executive functioning, and retrospective memory. However, little is known about prospective memory (PM) in PTSD, a clinically relevant aspect of episodic memory that supports the encoding and retrieval of intentions for future actions.

METHODS

Here we examined PM performance in 40 veterans with PTSD compared to 38 trauma comparison (TC) veterans who were exposed to combat but did not develop PTSD. All participants were administered the Memory for Intentions Test (MIST; Raskin, Buckheit, & Sherrod, 2010), a standardized and validated measure of PM, alongside a comprehensive neurocognitive battery, structured diagnostic interviews for psychiatric conditions, and behavioral questionnaires.

RESULTS

Veterans with PTSD performed moderately lower than TC on time-based PM, with errors primarily characterized as PM failure errors (i.e., omissions). However, groups did not differ in event-based PM, ongoing task performance, or post-test recognition of PM intentions for each trial. Lower time-based PM performance was specifically related to hyperarousal symptoms of PTSD. Time-based-performance was also associated with neuropsychological measures of retrospective memory and executive functions in the PTSD group. Nevertheless, PTSD was significantly associated with poorer PM above and beyond age and performance in retrospective memory and executive functions.

DISCUSSION

Results provide initial evidence of PM dysfunction in PTSD, especially in strategic monitoring during time-based PM tasks. Findings have potential implications for everyday functioning and health behaviors in persons with PTSD, and deserve replication and future study. (JINS, 2016, 22, 724-734).

The centrality of fear extinction in linking risk factors to PTSD: A narrative review

Recent prospective studies in emergency services have identified impaired fear extinction learning and memory to be a significant predictor of Posttraumatic Stress Disorder (PTSD), complementing a wealth of cross-sectional evidence of extinction deficits associated with the disorder. Additional fields of research show specific risk factors and biomarkers of the disorder, including candidate genotypes, stress and sex hormones, cognitive factors, and sleep disturbances. Studies in mostly nonclinical populations also reveal that the aforementioned factors are involved in fear extinction learning and memory. Here, we provide a comprehensive narrative review of the literature linking PTSD to these risk factors, and linking these risk factors to impaired fear extinction. On balance, the evidence suggests that fear extinction may play a role in the relationship between risk factors and PTSD. Should this notion hold true, this review carries important implications for the improvement of exposure-based treatments, as well as strategies for the implementation of treatment.

Prefrontal responses to Stroop tasks in subjects with post-traumatic stress disorder assessed by functional near infrared spectroscopy

Studies on posttraumatic stress disorder (PTSD) showing attentional deficits have implicated abnormal activities in the frontal lobe. In this study, we utilized multichannel functional near-infrared spectroscopy (fNIRS) to investigate selective attention-related hemodynamic activity in the prefrontal cortex among 15 combat-exposed war-zone veterans with PTSD and 13 age- and gender-matched healthy controls. While performing the incongruent Stroop task, healthy controls showed significant activations in the left lateral prefrontal cortex (LPFC) compared to baseline readings. This observation is consistent with previously reported results. In comparison, subjects with PTSD failed to activate left LPFC during the same Stroop task. Our observations may implicate that subjects with PTSD experienced difficulty in overcoming Stroop interference. We also observed significant negative correlation between task reaction times and hemodynamic responses from left LPFC during the incongruent Stroop task in the PTSD group. Regarding the methodology used in this study, we have learned that an appropriate design of Stroop paradigms is important for meeting an optimal cognitive load which can lead to better brain image contrasts in response to Stroop interference between healthy versus PTSD subjects. Overall, the feasibility of fNIRS for studying and mapping neural correlates of selective attention and interference in subjects with PTSD is reported.

Neurocognitive Correlates of Successful Treatment of PTSD in Female Veterans

BACKGROUND

The influence of psychotherapy on neurocognition in post-traumatic stress disorder (PTSD) has not been examined methodically. This is despite evidence that pre-treatment learning and memory has been associated with treatment success and that executive function theories emphasize weak executive functions (especially inhibition/switching) are associated with PTSD.

OBJECTIVES

To determine (1) if higher pre-treatment learning/memory, inhibition/switching, or both predict treatment success; and (2) if treatment success is associated with specific improvement in inhibition/switching and not learning/memory or working memory, another aspect of executive function.

METHODS

Pre-treatment neurocognition and neurocognitive changes (inhibition/switching, learning/memory, working memory) were examined in female veterans with PTSD. They were evaluated before and after 16-weeks of group psychotherapy for PTSD that included three counterbalanced modules (cognitive restructuring therapy, exposure therapy, skills training) with fidelity checks for therapist adherence.

RESULTS

Only pre-treatment learning/memory predicted better treatment outcome. Treatment success was associated with improvement in inhibition/switching only, even after controlling for mild traumatic brain injury, and changes in depressive symptoms, working memory, and learning/memory.

CONCLUSIONS

Our finding that learning/memory predicted treatment success is consistent with previous studies. We extended these studies by showing that the effect was restricted to learning/memory, which is contrary to the executive function theory of PTSD. In contrast, the fact that only inhibition/switching significantly improved with better treatment success is consistent with its potential importance in maintaining PTSD symptoms. Future research should determine whether inhibition/switching abilities are a risk for development and maintenance of PTSD or whether such abilities have a broader reciprocal relationship with PTSD symptom change. (JINS, 2016, 22, 643-651).

Parental bonding and neuropsychological performance are associated with episodic simulation of future events in trauma-exposed patients with major depressive disorder

INTRODUCTION

Major depressive disorder (MDD) and trauma-related disorders are associated with deficits in remembering the past and imagining the future (i.e., episodic simulation). We examined parental bonding and neuropsychological performance in relation to episodic simulation in trauma-exposed patients with recurrent MDD.

METHODS

Trauma-exposed patients with MDD (n = 21) and matched controls (n = 20) completed a future-oriented Autobiographical Interview, the Parental Bonding Instrument, and a standardized neuropsychological battery.

RESULTS

Patients with major depressive disorder generated fewer episodic details for future neutral events compared to controls. Although higher reported levels of maternal care were associated with increased specificity of negative future events among the patient group, higher maternal overprotection was related to decreased specificity of negative and positive future events. Higher levels of performance on measures of intelligence, verbal memory, executive functioning, and sustained attention were associated with increased specificity of future events.

CONCLUSIONS

Maternal relations during childhood and neuropsychological performance are related to the specificity of episodic simulation in adult patients with MDD. Childhood experience continues to influence memory performance into adulthood.

Does Early Psychological Intervention Promote Recovery From Posttraumatic Stress?

In the wake of the terrorist attacks at the World Trade Center, more than 9,000 counselors went to New York City to offer aid to rescue workers, families, and direct victims of the violence of September 11, 2001. These mental health professionals assumed that many New Yorkers were at high risk for developing posttraumatic stress disorder (PTSD), and they hoped that their interventions would mitigate psychological distress and prevent the emergence of this syndrome. Typically developing in response to horrific, life-threatening events, such as combat, rape, and earthquakes, PTSD is characterized by reexperiencing symptoms (e.g., intrusive recollections of the trauma, nightmares), emotional numbing and avoidance of reminders of the trauma, and hyperarousal (e.g., exaggerated startle, difficulty sleeping). People vary widely in their vulnerability for developing PTSD in the wake of trauma. For example, higher cognitive ability and strong social support buffer people against PTSD, whereas a family or personal history of emotional disorder heightens risk, as does negative appraisal of one's stress reactions (e.g., as a sign of personal weakness) and dissociation during the trauma (e.g., feeling unreal or experiencing time slowing down). However, the vast majority of trauma survivors recover from initial posttrauma reactions without professional help. Accordingly, the efficacy of interventions designed to mitigate acute distress and prevent long-term psychopathology, such as PTSD, needs to be evaluated against the effects of natural recovery. The need for controlled evaluations of early interventions has only recently been widely acknowledged.

Psychological debriefing—the most widely used method—has undergone increasing empirical scrutiny, and the results have been disappointing. Although the majority of debriefed survivors describe the experience as helpful, there is no convincing evidence that debriefing reduces the incidence of PTSD, and some controlled studies suggest that it may impede natural recovery from trauma. Most studies show that individuals who receive debriefing fare no better than those who do not receive debriefing. Methodological limitations have complicated interpretation of the data, and an intense controversy has developed regarding how best to help people in the immediate wake of trauma.

Recent published recommendations suggest that individuals providing crisis intervention in the immediate aftermath of the event should carefully assess trauma survivors' needs and offer support as necessary, without forcing survivors to disclose their personal thoughts and feelings about the event. Providing information about the trauma and its consequences is also important. However, research evaluating the efficacy of such “psychological first aid” is needed.

Some researchers have developed early interventions to treat individuals who are already showing marked stress symptoms, and have tested methods of identifying those at risk for chronic PTSD. The single most important indicator of subsequent risk for chronic PTSD appears to be the severity or number of posttrauma symptoms from about 1 to 2 weeks after the event onward (provided that the event is over and that there is no ongoing threat).

Cognitive-behavioral treatments differ from crisis intervention (e.g., debriefing) in that they are delivered weeks or months after the trauma, and therefore constitute a form of psychotherapy, not immediate emotional first aid. Several controlled trials suggest that certain cognitive-behavioral therapy methods may reduce the incidence of PTSD among people exposed to traumatic events. These methods are more effective than either supportive counseling or no intervention.

In this monograph, we review risk factors for PTSD, research on psychological debriefing, recent recommendations for crisis intervention and the identification of individuals at risk of chronic PTSD, and research on early interventions based on cognitive-behavioral therapy. We close by placing the controversy regarding early aid for trauma survivors in its social, political, and economic context.

Attentional processes in posttraumatic stress disorder and the associated changes in neural functioning

Posttraumatic Stress Disorder (PTSD) is associated with alterations in attention at the behavioral and neural levels. However, there are conflicting findings regarding the specific type of attention impairments present in PTSD, as the commonly used tests of attention do not isolate the mechanisms behind attention abnormalities, and the constructs measured do not map onto the neurocircuits governing attention. Here, we review the literature on attention processing in PTSD and offer directions for future research to clarify these unanswered questions. First, using instruments that allow assessment of behavioral and neurophysiological attention components will be necessary to understand attention deficits in PTSD. Second, focus on intra-individual variability in addition to assessment of central tendency may help clarify some of the mixed findings. Third, longitudinal studies on attentional processes are warranted to determine how attention contributes to the development and maintenance of PTSD. Integration of behavioral and neural measures of attention will be useful in understanding the pathophysiology of PTSD.

Neuropsychological Functioning in Veterans with Posttraumatic Stress Disorder: Associations with Performance Validity, Comorbidities, and Functional Outcomes

OBJECTIVES

Numerous studies have shown that individuals with posttraumatic stress disorder (PTSD) display reduced performances on neuropsychological tests, although most prior research has not adequately accounted for comorbidities or performance validity concerns that are common in this population and could partially account for the observed neurocognitive findings. Moreover, few studies have examined the functional implications of neuropsychological results in PTSD.

METHODS

We examined neuropsychological functioning in 44 veterans with PTSD and 40 veteran trauma comparison (TC) participants with combat exposure and no PTSD.

RESULTS

After excluding four veterans with PTSD for performance validity concerns, multivariate analyses of variance by neurocognitive domain revealed significantly worse performance by the PTSD group in the domains of speed of information processing (p=.035) and executive functions (p=.017), but no group differences in attention/working memory, verbal/language functioning, visuoconstruction, or episodic memory. Group differences by PTSD status were still present after covarying for depression, a history of head injuries, and substance use disorders. Executive functioning performance was associated with poorer self-reported occupational functioning and physical health-related quality of life, while speed of information processing performance was associated with poorer physical health-related quality of life.

DISCUSSION

These results are generally consistent with a fronto-limbic conceptualization of PTSD-associated neuropsychological dysfunction and show that cognitive functioning may be associated with critical functional outcomes. Taken together, results suggest that consideration of neurocognitive functioning may enhance the clinical management of individuals with PTSD.

Propranolol's impact on cognitive performance in post-traumatic stress disorder

BACKGROUND

Propranolol has effectively diminished fear-based emotional memories in posttraumatic stress disorder (PTSD) and this effect has been attributed to traumatic memory reconsolidation blockade. However, propranolol may also exert cognitive effects by modulating stress and arousal.

METHOD

Within a randomized double-blind placebo controlled trial, propranolol's impact on cognitive functioning was examined in individuals who were diagnosed with chronic PTSD. Participants received a single dose of 1mg/kg of propranolol (n=20) or placebo (n=21), and completed subtests of the Wechsler Adult Intelligence Scale third edition (WAIS-III). PTSD symptoms were assessed 1 week before and after treatment by the Impact of Event Scale Revised (IES-R).

RESULTS

The propranolol group performed significantly better on the Processing Speed composite measure compared to the placebo group. Furthermore, greater heart rate decreases were associated with higher Perceptual Organization performance, within the propranolol group.

LIMITATIONS

The generalizability of results may have been reduced as participants were treatment seeking; the sample size was small and included a greater proportion of females.This study could not assess whether pre-existing psychological function influenced cognitive performance, post-trauma. Future studies might consider including a non-PTSD control group to determine if our findings are specific to propranolol's effect on PTSD associated cognitive impairment.

CONCLUSIONS

Our preliminary results demonstrated that cognitive functioning improved following propranolol administration in PTSD patients. The implications are discussed with regards to the processing of traumatic events.

Changes in temporal attention inhibition following prolonged exposure and sertraline in the treatment of PTSD

OBJECTIVE

Attentional inhibitory deficits expressed as difficulty ignoring irrelevant stimuli in the pursuit of goal-directed behavior may serve as a fundamental mechanism of posttraumatic stress disorder (PTSD). Evidence of inhibitory processes as central to extinction suggests that exposure-based treatments may act more directly on the inhibitory deficits implicated in PTSD, whereas, in facilitating serotonergic neurotransmission, selective serotonin reuptake inhibitors (SSRIs) may be less direct and bring about general neurochemical changes in the fear circuitry. If these inhibitory deficits underlie PTSD, then inhibition should improve with successful treatment, with those treated with prolonged exposure (PE) potentially resulting in greater changes in inhibition than those treated with sertraline.

METHOD

Changes in temporal attentional inhibition, using an attentional blink (AB) paradigm, were examined at pre- and posttreatment in 49 individuals (74.5% female, 66.7% Caucasian, age M = 37.69, SD = 12.8 years) with chronic PTSD. Participants completed 10 weeks of either PE or sertraline.

RESULTS

Individuals who made greater improvements with PE showed faster improvements in temporal inhibition on the critical inhibitory lag of AB than those who made greater improvements with sertraline (d = 0.94). These changes could not be accounted for by basic attention.

CONCLUSIONS

Greater improvement in fundamental attentional inhibitory processes with better treatment response to PE, compared with sertraline, suggests potential specificity in how PTSD treatments normalize inhibitory processes, such that exposure-based treatments like PE may target inhibitory processes and improve basic inhibitory functioning.

Breakdown of Inter-Hemispheric Connectivity Is Associated with Posttraumatic Symptomatology and Memory Impairment

Altered brain anatomy in specific gray-matter regions has been shown in patients with posttraumatic stress disorder (PTSD). Recently, white-matter tracts have become a focus of research in PTSD. The corpus callosum (CC) is the principal white-matter fiber bundle, crucial in relaying sensory, motor and cognitive information between hemispheres. Alterations in CC fibers have been reported in PTSD and might be assumed to underlie substantial behavioral and cognitive sequelae; however most diffusion tensor imaging (DTI) studies in adult-onset PTSD failed to address the clinical correlates between imaging and PTSD symptoms severity, behavioral manifestation and cognitive functions. In the current study we examined (a) to what extent microstructural integrity of the CC is associated with memory performance and (b) whether imaging and cognitive parameters are associated with PTSD symptom severity. DTI data were obtained and fractional anisotropy (FA) values were computed for 16 patients and 14 controls. PTSD symptom severity was assessed by employing the clinician administered PTSD scale (CAPS) and memory was tested using a task probing item and associative memory for words and pictures. Significant correlations were found between PTSD symptoms severity, memory accuracy and reaction-time to CC FA values in the PTSD group. This study demonstrates meaningful clinical and cognitive correlates of microstructural connectivity. These results have implications for diagnostic tools and future studies aimed at identifying individuals at risk for PTSD.

The maternal brain and its plasticity in humans

This article is part of a Special Issue "Parental Care". Early mother-infant relationships play important roles in infants' optimal development. New mothers undergo neurobiological changes that support developing mother-infant relationships regardless of great individual differences in those relationships. In this article, we review the neural plasticity in human mothers' brains based on functional magnetic resonance imaging (fMRI) studies. First, we review the neural circuits that are involved in establishing and maintaining mother-infant relationships. Second, we discuss early postpartum factors (e.g., birth and feeding methods, hormones, and parental sensitivity) that are associated with individual differences in maternal brain neuroplasticity. Third, we discuss abnormal changes in the maternal brain related to psychopathology (i.e., postpartum depression, posttraumatic stress disorder, substance abuse) and potential brain remodeling associated with interventions. Last, we highlight potentially important future research directions to better understand normative changes in the maternal brain and risks for abnormal changes that may disrupt early mother-infant relationships.

An analysis of inhibitory functioning in individuals with chronic posttraumatic stress disorder

Cognitive abnormalities in posttraumatic stress disorder (PTSD) may be a function of underlying inhibitory deficits. Prepulse inhibition (PPI) and attentional blink (AB) are paradigms thought to assess inhibition. Using a sample of 28 individuals with PTSD compared to 20 trauma-exposed and 19 healthy individuals, PPI was examined using white noise that was preceded by a tone, and AB was examined using a presentation of letters in a stream of numbers. Relative to the control group, the PTSD and trauma-exposed groups did not follow the u-shaped pattern in AB, suggesting trauma-exposure and subsequent PTSD are associated with similar impairment in attention. Individuals with PTSD showed reduced PPI compared to trauma-exposed and healthy individuals, suggesting individuals with PTSD exhibit faulty automatic processing. For individuals with PTSD, PTSD severity was associated with a decline in PPI. These findings suggest a general faulty inhibitory mechanism associated with trauma exposure and PTSD.

Magnetic Resonance Therapy Improves Clinical Phenotype and EEG Alpha Power in Posttraumatic Stress Disorder

Background:

Posttraumatic stress disorder (PTSD) is a disabling and prevalent psychiatric disorder with limited effective treatment options. In addition to the clinical features of the disease, pathologic changes in the electroencephalogram (EEG), including decreased alpha power, have been reported.

Objectives:

To determine if magnetic brain stimulation can induce normalization of EEG abnormalities and improve clinical symptoms in PTSD in a preliminary, open-label evaluation.

Materials and Methods:

We reviewed prospectively-collected data on 21 veterans that were consecutively-treated for PTSD. Magnetic resonance therapy (MRT) was administered for two weeks at treatment frequencies based on frequency-domain analysis of each patient’s dominant alpha-band EEG frequencies and resting heart rate. Patients were evaluated on the PTSD checklist (PCL-M) and pre- and post-treatment EEGs before and after MRT.

Results:

Of the 21 patients who initiated therapy, 16 completed treatment. Clinical improvements on the PCL-M were seen in these 16 patients, with an average pre-treatment score of 54.9 and post-treatment score of 31.8 (P < 0.001). In addition, relative global EEG alpha-band (8 - 13 Hz) power increased from 32.0 to 38.5 percent (P = 0.013), and EEG delta-band (1 - 4 Hz) power decreased from 32.3 percent to 26.8 percent (P = 0.028).

Conclusions:

These open-label data show trends toward normalization of EEG and concomitant clinical improvement using magnetic stimulation for PTSD.

Cognitive disruptions in stress-related psychiatric disorders: A role for corticotropin releasing factor (CRF)

This article is part of a Special Issue "SBN 2014". Stress is a potential etiology contributor to both post-traumatic stress disorders (PTSD) and major depression. One stress-related neuropeptide that is hypersecreted in these disorders is corticotropin releasing factor (CRF). Dysregulation of CRF has long been linked to the emotion and mood symptoms that characterize PTSD and depression. However, the idea that CRF also mediates the cognitive disruptions observed in patients with these disorders has received less attention. Here we review literature indicating that CRF can alter cognitive functions. Detailed are anatomical studies revealing that CRF is poised to modulate regions required for learning and memory. We also describe preclinical behavioral studies that demonstrate CRF's ability to alter fear conditioning, impair memory consolidation, and alter a number of executive functions, including attention and cognitive flexibility. The implications of these findings for the etiology and treatment of the cognitive impairments observed in stress-related psychiatric disorders are described.

Avoidance symptoms and delayed verbal memory are associated with post-traumatic stress symptoms in female victims of sexual violence

BACKGROUND

Victimization by sexual violence is strongly associated with the development of posttraumatic stress disorder (PTSD). While several psychological and cognitive factors are known to be associated with PTSD prognosis, multivariable analysis is scarce. This study examined factors affecting the severity of PTSD symptoms in early stage of traumatic experience of sexual violence, including initial post-traumatic symptoms and cognitive characteristics.

METHODS

Participants were recruited from the center for women and children victims of violence in a university hospital. Thirty-four sexual assault victims were assessed at the baseline and the second visit one to five months after the baseline. At the baseline, an array of posttraumatic symptoms and cognitive functions were measured: at follow-up, PTSD symptoms were determined by Clinician Administered PTSD Scale.

RESULTS

Stepwise multiple regression showed that avoidance symptoms (β = 0.551, P < 0.01) and delayed verbal memory (β = -0.331, P < 0.05) at early stage of trauma predicted the severity of PTSD symptoms one to five month later. The regression model, factoring in avoidance and delayed verbal memory, showed a 34.9% explanatory power regarding the PTSD symptom severity.

CONCLUSION

This study suggests that avoidance symptoms and verbal memory at the early stage of trauma are associated with later PTSD symptoms. It is also suggested that early intervention targeting avoidance symptoms may be beneficial in decreasing PTSD symptoms.

Executive functions as a potential neurocognitive endophenotype in anxiety disorders: A systematic review considering DSM-IV and DSM-5 diagnostic criteria classification

Evidence in the literature indicates that neurocognitive impairments may represent endophenotypes in psychiatric disorders.

Objective

This study aimed to conduct a systematic review on executive functions as a potential neurocognitive endophenotype in anxiety disorder diagnosis according to the DSM-IV and DSM-5 classifications.

Methods

A literature search of the LILACS, Cochrane Library, Index Psi Periódicos Técnico-Científicos, PubMed and PsycInfo databases was conducted, with no time limits. Of the 259 studies found, 14 were included in this review.

Results

Only studies on obsessive-compulsive disorder (OCD) were found. The executive function components of decision-making, planning, response inhibition, behavioral reversal/alternation, reversal learning and set-shifting/cognitive flexibility were considered to be a neurocognitive endophenotypes in OCD.

Conclusion

Further studies on executive functions as a neurocognitive endophenotype in other anxiety disorders are needed since these may have different neurocognitive endophenotypes and require other prevention and treatment approaches.

Effects of Posttraumatic Stress Disorder and Metabolic Syndrome on Cognitive Aging in Veterans

PURPOSE OF THE STUDY

With the influx of veterans entering older adulthood, it is increasingly important to understand risk factors for cognitive decline. Posttraumatic stress disorder (PTSD) and the metabolic syndrome (MetS) are highly prevalent in older veterans. Although both increase risk for cognitive decline and often co-occur, it is unclear how they may interact to negatively impact cognition. The aim of this cross-sectional study was to investigate associations among PTSD, MetS, and cognitive function in older veterans. We hypothesized that co-occurring PTSD and MetS would be associated with worse cognitive performance than seen in either illness alone.

DESIGN AND METHODS

Participants completed cognitive testing to assess processing speed, verbal memory, and executive function. Data from 204 male veterans aged 55-89 were analyzed with the use of hierarchical multiple regression models.

RESULTS

Veterans with MetS demonstrated poorer performance on tasks of executive function (response inhibition and cognitive set shifting) and immediate verbal memory regardless of PTSD status. There was an interaction between MetS and PTSD on delayed verbal memory, suggesting that the negative impact of MetS on verbal memory was only significant for veterans not classified as having PTSD.

IMPLICATIONS

This is the first study to examine the impact of comorbid PTSD and MetS on cognition. The results suggest that MetS is associated with poorer verbal learning and executive functioning independent of PTSD. We discuss the necessity of monitoring cerebrovascular risk factors and providing early behavioral and/or pharmaceutical interventions to lessen the risk of cognitive decline in older age.

Role of morality in the experience of guilt and shame within the armed forces

OBJECTIVE

Despite advances in our understanding of mental health issues among military forces, a large proportion of military personnel continue to exhibit deployment-related psychological issues. Recent work has identified symptoms of guilt and shame related to moral injury as contributing significantly to combat-related mental health issues. This systematic scoping review explores the association between morality and symptoms of guilt and shame within military forces.

METHOD

A search of the literature pertaining to guilt, shame and morality within military samples was conducted.

RESULTS

Nineteen articles were selected for review. There is strong evidence linking exposure to and the perceived perpetration of moral transgressions with experiences of guilt and shame. Critically, symptoms of guilt and shame were related to adverse mental health outcomes, particularly the onset of post-traumatic stress disorder (PTSD). No studies have explored moral judgment in conjunction with assessments of guilt or moral injury.

CONCLUSION

These findings have important implications for the prevention and treatment of PTSD-related symptoms in military samples. By measuring moral judgment prior to deployment, it may be possible to predict the likelihood of incurring moral injuries and the development of associated symptoms. Early intervention programmes aimed at ameliorating guilt and shame are required to prevent the long-term development of deployment-related psychological distress.

Sleep disturbances, TBI and PTSD: Implications for treatment and recovery

Post-Traumatic Stress Disorder (PTSD), traumatic brain injury (TBI), and sleep problems significantly affect recovery and functional status in military personnel and Veterans returning from combat. Despite recent attention, sleep is understudied in the Veteran population. Few treatments and rehabilitation protocols target sleep, although poor sleep remains at clinical levels and continues to adversely impact functioning even after the resolution of PTSD or mild TBI symptoms. Recent developments in non-pharmacologic sleep treatments have proven efficacious as stand-alone interventions and have potential to improve treatment outcomes by augmenting traditional behavioral and cognitive therapies. This review discusses the extensive scope of work in the area of sleep as it relates to TBI and PTSD, including pathophysiology and neurobiology of sleep; existing and emerging treatment options; as well as methodological issues in sleep measurements for TBI and PTSD. Understanding sleep problems and their role in the development and maintenance of PTSD and TBI symptoms may lead to improvement in overall treatment outcomes while offering a non-stigmatizing entry in mental health services and make current treatments more comprehensive by helping to address a broader spectrum of difficulties.

An Open-Label Trial of Memantine for Cognitive Impairment in Patients with Posttraumatic Stress Disorder

Background. Studies using standard neuropsychological instruments have demonstrated memory deficits in patients with PTSD. We evaluated the efficacy and safety of the N-methyl-D-aspartate antagonist memantine in veterans with PTSD and cognitive impairment. Methods. Twenty-six veterans with PTSD and cognitive impairment received 16 weeks of memantine in an open-label fashion. Cognition was assessed using the Spatial Span, Logical Memory I, and Letter-Number Sequencing subtests of the Wechsler Memory Scale III and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). RBANS measures attention, language, visuospatial skills, and immediate and delayed memories. The Clinician Administered PTSD Scale (CAPS), Hamilton Depression Scale (HAM-D), Hamilton Anxiety Scale (HAM-A), Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q), and Sheehan Disability Scale (SDS) were secondary outcome measures. Results. There was a significant improvement in RBANS, both total and subscale scores (P < 0.05), over time. There was a reduction in total CAPS scores, avoidance/numbing symptoms (CAPS-C) and hyperarousal symptoms (CAPS-D), HAM-D, Q-LES-Q, and SDS scores. However, there was no reduction in reexperiencing (CAPS-B) and HAM-A scores. Memantine was well tolerated. Conclusions. Memantine improved cognitive symptoms, PTSD symptoms, and mood in veterans with PTSD. Randomized double-blind studies are needed to validate these preliminary observations.

A systematic review and meta-analysis of magnetic resonance imaging measurement of structural volumes in posttraumatic stress disorder

Posttraumatic stress disorder (PTSD) is a debilitating condition associated with mild to moderate cognitive impairment and with a prevalence rate of up to 22% in veterans. This systematic review and quantitative meta-analysis explore volumetric differences of three key structural brain regions (hippocampus, amygdala and anterior cingulate cortex (ACC)), all of which have been implicated in dysfunction of both salience network (SN) and default mode network (DMN) in PTSD sufferers. A literature search was conducted in Embase, Medline, PubMed and PsycINFO in May 2013. Fifty-nine volumetric analyses from 44 articles were examined and included (36 hippocampus, 14 amygdala and nine ACC) with n=846 PTSD participants, n=520 healthy controls (HCs) and n=624 traumatised controls (TCs). Nine statistical tests were performed for each of the three regions of interest (ROIs), measuring volume differences in PTSD subjects, healthy and traumatised controls. Hippocampal volume was reduced in subjects with PTSD, with a greater reduction in the left hippocampus. A medium effect size reduction was found in bilateral amygdala volume when compared with findings in healthy controls; however, no significant differences in amygdala volume between PTSD subjects and trauma-exposed controls were found. Significant volume reductions were found bilaterally in the ACC. While often well matched with their respective control groups, the samples of PTSD subjects composed from the source studies used in the meta-analyses are limited in their homogeneity. The current findings of reduced hippocampal volume in subjects with PTSD are consistent with the existing literature. Amygdala volumes did not show significant reductions in PTSD subjects when compared with volumes in trauma-exposed controls-congruous with reported symptoms of hypervigilance and increased propensity in acquisition of conditioned fear memories-but a significant reduction was found in the combined left and right hemisphere volume analysis when compared with healthy controls. Bilateral volume reductions in the ACC may underpin the attentional deficits and inabilities to modulate emotions that are characteristically associated with PTSD patients.

Theta, mental flexibility, and post-traumatic stress disorder: connecting in the parietal cortex

Post-traumatic stress disorder (PTSD) is a mental health injury characterised by re-experiencing, avoidance, numbing and hyperarousal. Whilst the aetiology of the disorder is relatively well understood, there is debate about the prevalence of cognitive sequelae that manifest in PTSD. In particular, there are conflicting reports about deficits in executive function and mental flexibility. Even less is known about the neural changes that underlie such deficits. Here, we used magnetoencephalography to study differences in functional connectivity during a mental flexibility task in combat-related PTSD (all males, mean age = 37.4, n = 18) versus a military control (all males, mean age = 33.05, n = 19) group. We observed large-scale increases in theta connectivity in the PTSD group compared to controls. The PTSD group performance was compromised in the more attentionally-demanding task and this was characterised by 'late-stage' theta hyperconnectivity, concentrated in network connections involving right parietal cortex. Furthermore, we observed significant correlations with the connectivity strength in this region with a number of cognitive-behavioural outcomes, including measures of attention, depression and anxiety. These findings suggest atypical coordination of neural synchronisation in large scale networks contributes to deficits in mental flexibility for PTSD populations in timed, attentionally-demanding tasks, and this propensity toward network hyperconnectivity may play a more general role in the cognitive sequelae evident in this disorder.

The nature of white matter abnormalities in blast-related mild traumatic brain injury

Blast-related traumatic brain injury (TBI) has been a common injury among returning troops due to the widespread use of improvised explosive devices in the Iraq and Afghanistan Wars. As most of the TBIs sustained are in the mild range, brain changes may not be detected by standard clinical imaging techniques such as CT. Furthermore, the functional significance of these types of injuries is currently being debated. However, accumulating evidence suggests that diffusion tensor imaging (DTI) is sensitive to subtle white matter abnormalities and may be especially useful in detecting mild TBI (mTBI). The primary aim of this study was to use DTI to characterize the nature of white matter abnormalities following blast-related mTBI, and in particular, examine the extent to which mTBI-related white matter abnormalities are region-specific or spatially heterogeneous. In addition, we examined whether mTBI with loss of consciousness (LOC) was associated with more extensive white matter abnormality than mTBI without LOC, as well as the potential moderating effect of number of blast exposures. A second aim was to examine the relationship between white matter integrity and neurocognitive function. Finally, a third aim was to examine the contribution of PTSD symptom severity to observed white matter alterations. One hundred fourteen OEF/OIF veterans underwent DTI and neuropsychological examination and were divided into three groups including a control group, blast-related mTBI without LOC (mTBI - LOC) group, and blast-related mTBI with LOC (mTBI + LOC) group. Hierarchical regression models were used to examine the extent to which mTBI and PTSD predicted white matter abnormalities using two approaches: 1) a region-specific analysis and 2) a measure of spatial heterogeneity. Neurocognitive composite scores were calculated for executive functions, attention, memory, and psychomotor speed. Results showed that blast-related mTBI + LOC was associated with greater odds of having spatially heterogeneous white matter abnormalities. Region-specific reduction in fractional anisotropy (FA) in the left retrolenticular part of the internal capsule was observed in the mTBI + LOC group as the number of blast exposures increased. A mediation analysis revealed that mTBI + LOC indirectly influenced verbal memory performance through its effect on white matter integrity. PTSD was not associated with spatially heterogeneous white matter abnormalities. However, there was a suggestion that at higher levels of PTSD symptom severity, LOC was associated with reduced FA in the left retrolenticular part of the internal capsule. These results support postmortem reports of diffuse axonal injury following mTBI and suggest that injuries with LOC involvement may be particularly detrimental to white matter integrity. Furthermore, these results suggest that LOC-associated white matter abnormalities in turn influence neurocognitive function.

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Diffusion tensor imaging was used to examine blast mild traumatic brain injury.

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114 Iraq and Afghanistan War veterans were studied.

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mTBI + loss of consciousness (LOC) was associated with white matter abnormalities.

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mTBI + LOC influenced verbal memory through white matter integrity.

The neurocognitive performance of female veterans with posttraumatic stress disorder

Neurocognitive problems are common with posttraumatic stress disorder (PTSD) and are important to understand because of their association with the success of PTSD treatment and its potential neural correlates. To our knowledge, this is the first neurocognitive study in an all-female U.S. veteran sample, some of whom had PTSD. We examined neurocognitive performance and assessed whether learning deficits, common in PTSD, were associated with executive functioning. Veterans with PTSD (n = 56) and without (n = 53) were evaluated for psychiatric and neurocognitive status. The PTSD group had a lower estimated IQ (d = 0.53) and performed more poorly on all neurocognitive domains (d range = 0.57-0.88), except verbal retention (d = 0.04). A subset of the 2 groups that were matched on IQ and demographics similarly demonstrated poorer performance for the PTSD group on all neurocognitive domains (d range = 0.52-0.79), except verbal retention (d = 0.15). Within the PTSD group, executive functioning accounted for significant variance in verbal learning over and above IQ and processing speed (ΔR(2) = .06), as well as depression (ΔR(2) = .07) and PTSD severity (ΔR(2) = .06). This study demonstrated that female veterans with PTSD performed more poorly than females without PTSD on several neurocognitive domains, including verbal learning, processing speed, and executive functioning. Replication of these results using a control group of veterans with more similar trauma exposure, history of mild traumatic brain injury, and psychiatric comorbidities would solidify these findings.

Children's cognitive performance and selective attention following recent community violence

Research has shown robust relationships between community violence and psychopathology, yet relatively little is known about the ways in which community violence may affect cognitive performance and attention. The present study estimates the effects of police-reported community violence on 359 urban children's performance on a computerized neuropsychological task using a quasi-experimental fixed-effects design. Living in close proximity to a recent violent crime predicted faster but marginally less accurate task performance for the full sample, evolutionarily adaptive patterns of "vigilant" attention (i.e., less attention toward positive stimuli, more attention toward negative stimuli) for children reporting low trait anxiety, and potentially maladaptive patterns of "avoidant" attention for highly anxious children. These results suggest that community violence can directly affect children's cognitive performance while also having different (and potentially orthogonal) impacts on attention deployment depending on children's levels of biobehavioral risk. Implications for mental health and sociological research are discussed.

Neural correlates of inhibition and contextual cue processing related to treatment response in PTSD

Thirty to fifty percent of posttraumatic stress disorder (PTSD) patients do not respond to treatment. Understanding the neural mechanisms underlying treatment response could contribute to improve response rates. PTSD is often associated with decreased inhibition of fear responses in a safe environment. Importantly, the mechanism of effective treatment (psychotherapy) relies on inhibition and so-called contextual cue processing. Therefore, we investigate inhibition and contextual cue processing in the context of treatment. Forty-one male war veterans with PTSD and 22 healthy male war veterans (combat controls) were scanned twice with a 6- to 8-month interval, in which PTSD patients received treatment (psychotherapy). We distinguished treatment responders from nonresponders on the base of percentage symptom decrease. Inhibition and contextual cue processing were assessed with the stop-signal anticipation task. Behavioral and functional MRI measures were compared between PTSD patients and combat controls, and between responders and nonresponders using repeated measures analyses. PTSD patients showed behavioral and neural deficits in inhibition and contextual cue processing at both time points compared with combat controls. These deficits were unaffected by treatment; therefore, they likely represent vulnerability factors or scar aspects of PTSD. Second, responders showed increased pretreatment activation of the left inferior parietal lobe (IPL) during contextual cue processing compared with nonresponders. Moreover, left IPL activation predicted percentage symptom improvement. The IPL has an important role in contextual cue processing, and may therefore facilitate the effect of psychotherapy. Hence, increased left IPL activation may represent a potential predictive biomarker for PTSD treatment response.

Different Neural Mechanisms Underlie Deficits in Mental Flexibility in Post-Traumatic Stress Disorder Compared to Mild Traumatic Brain Injury

Mental flexibility is a core executive function that underlies the ability to adapt to changing situations and respond to new information. Individuals with post-traumatic stress disorder (PTSD) and mild traumatic brain injury (mTBI) complain of a number of executive function difficulties, one of which is mental inflexibility or an inability to switch between concepts. While the behavioral presentation of mental inflexibility is similar in those with PTSD or mTBI, we hypothesized that the differences in their etiology would manifest as differences in their underlying brain processing. The neural substrates of mental flexibility have been examined with a number of neuroimaging modalities. Functional magnetic resonance imaging has elucidated the brain regions involved, whereas electroencephalography has been applied to understand the timing of the brain activations. Magnetoencephalography, with its high temporal and spatial resolution, has more recently been used to delineate the spatiotemporal progression of brain processes involved in mental flexibility and has been applied to the study of clinical populations. In a number of separate studies, our group has compared the source localization and brain connectivity during a mental flexibility set-shifting task in a group of soldiers with PTSD and civilians with an acute mTBI. In this article, we review the results from these studies and integrate the data between groups to compare and contrast differences in behavioral, neural, and connectivity findings. We show that the different etiologies of PTSD and mTBI are expressed as distinct neural profiles for mental flexibility that differentiate the groups despite their similar clinical presentations.

A quantitative meta-analysis of neurocognitive functioning in posttraumatic stress disorder

Posttraumatic stress disorder (PTSD) is associated with regional alterations in brain structure and function that are hypothesized to contribute to symptoms and cognitive deficits associated with the disorder. We present here the first systematic meta-analysis of neurocognitive outcomes associated with PTSD to examine a broad range of cognitive domains and describe the profile of cognitive deficits, as well as modifying clinical factors and study characteristics. This report is based on data from 60 studies totaling 4,108 participants, including 1,779 with PTSD, 1,446 trauma-exposed comparison participants, and 895 healthy comparison participants without trauma exposure. Effect-size estimates were calculated using a mixed-effects meta-analysis for 9 cognitive domains: attention/working memory, executive functions, verbal learning, verbal memory, visual learning, visual memory, language, speed of information processing, and visuospatial abilities. Analyses revealed significant neurocognitive effects associated with PTSD, although these ranged widely in magnitude, with the largest effect sizes in verbal learning (d = -.62), speed of information processing (d = -.59), attention/working memory (d = -.50), and verbal memory (d =-.46). Effect-size estimates were significantly larger in treatment-seeking than community samples and in studies that did not exclude participants with attention-deficit/hyperactivity disorder, and effect sizes were affected by between-group IQ discrepancies and the gender composition of the PTSD groups. Our findings indicate that consideration of neuropsychological functioning in attention, verbal memory, and speed of information processing may have important implications for the effective clinical management of persons with PTSD. Results are further discussed in the context of cognitive models of PTSD and the limitations of this literature.

Grape powder prevents cognitive, behavioral, and biochemical impairments in a rat model of posttraumatic stress disorder

Previously, using the single-prolonged stress (SPS) rat model of posttraumatic stress disorder, we reported that moderate treadmill exercise, via modulation of oxidative stress-related mechanisms, rescued anxiety- and depression-like behaviors and reversed SPS-induced memory impairment. In this study using the SPS model (2-hour restrain, 20-minute forced swimming, 15-minute rest, and 1-2-minute diethyl ether exposure), we hypothesized that antioxidant rich grape powder (GP) prevents SPS-induced behavioral and memory impairment in rats. Male Sprague Dawley rats were randomly assigned into control (CON) (provided tap water), SPS (provided tap water), GP-SPS (provided 15 g/L GP in tap water for 3 weeks followed by SPS), or GP-CON (3 weeks of GP followed by CON exposure). Anxiety- and depression-like behaviors were significantly greater in SPS rats, when compared with CON- or GP-treated rats, and GP reversed these behavioral deficits. Single-prolonged stress rats made significantly more errors in both short- and long-term memory tests compared with CON- or GP-treated rats, which were prevented in GP-SPS rats. Grape powder prevented SPS-induced increase in plasma corticosterone level. Furthermore, brain-derived neurotrophic factor levels were significantly decreased in amygdala of SPS rats but not in GP-SPS rats compared with CON or (GP-CON) rats. In addition, GP significantly increased acetylated histone 3 and histone deacetylase 5 in hippocampus and amygdala of SPS rats as compared with CON or GP-CON rats. In conclusion, we suggest protective role of GP in SPS-induced behavioral, cognitive, and biochemical impairments in rats. Perhaps, epigenetic regulation of brain-derived neurotrophic factor enables GP-mediated prevention of SPS-induced deficits in rats.

An experience sampling study of PTSD and alcohol-related problems

Posttraumatic stress disorder (PTSD) represents a debilitating psychiatric condition that is affecting the lives of many returning veterans. PTSD and alcohol use and dependence are highly comorbid. The purpose of this study was to understand the functional mechanisms between PTSD and alcohol use and problems. Specifically, the role of negative urgency and emotional intelligence were investigated as vulnerability and resiliency factors, respectively. This study utilized experience sampling to test associations between PTSD symptoms and alcohol use and related problems in a sample of 90 OIF/OEF veterans. Participants completed 8 brief questionnaires daily for 2 weeks on palmtop computers. Elevations in PTSD symptoms during the day were associated with subsequent increases in alcohol use and associated problems that night. PTSD symptoms were associated with greater problems above and beyond the effect of drinking level at both the within- and between- person level. Emotional intelligence was associated with lower negative urgency, fewer PTSD symptoms, and less alcohol use and associated problems. The effects of emotional intelligence were primarily indirect via negative urgency and the effects of negative urgency on alcohol use and problems were indirect via its positive association with PTSD symptoms. Hypothesized cross-level effects of emotional intelligence and negative urgency were not supported. The findings suggest a functional association between PTSD symptoms and alcohol consumption. The association between PTSD symptoms and alcohol consumption is consistent with a self-medication model. However, the significant associations between PTSD symptoms and alcohol problems, after controlling for use level, suggest a broader role of dysregulation.

Clinical and neuropsychological predictors of posttraumatic stress disorder

Although acute responses to traumatic stress generally resolve within a few weeks, some individuals experience severe and persistent problems, such as posttraumatic stress disorder (PTSD). While studies have identified a variety of predictors of PTSD, not all data are consistent. This longitudinal study examined the predictive power of neurocognitive deficits with regard to PTSD severity.One hundred thirty one road traffic collision (RTC) survivors were included within 2 weeks of the RTC and followed up 3 and 6 months later to determine severity of PTSD.Impairment on tests of information processing, executive functioning, verbal learning, and motor speed predicted PTSD severity when neuropsychological, clinical, and sociodemographic factors were all taken into account. Clinical variables (initial symptoms, psychiatric diagnoses, disability, trait anxiety, perceived stress, negative cognitions, and sleep) were associated with 3 and 6-month PTSD severity, but only trait anxiety was predictive of PTSD severity. Ethnicity and education were also found to be predictive.These findings suggest implementation of a holistic approach to screening for PTSD and support a need for interventions that target neurocognitive, clinical, and social variables. Early targeted profiling of this group of trauma survivors can inform early clinical interventions and policy.

Cognition, functional capacity, and self-reported disability in women with posttraumatic stress disorder: examining the convergence of performance-based measures and self-reports

Individuals with posttraumatic stress disorder (PTSD) experience cognitive impairments and disability in everyday activities. In other neuropsychiatric disorders, impairments in cognition and functional capacity (i.e., the ability to perform everyday tasks) are associated with impairments in real-world functioning, independent of symptom severity. To date, no studies of functional capacity have been conducted in PTSD. Seventy-three women with moderate to severe PTSD underwent assessment with measures of cognition (MATRICS Consensus Cognitive Battery: MCCB), functional capacity (UCSD Performance-Based Skills Assessment-Brief: UPSA-B), PTSD (Clinician-Administered PTSD Scale and PTSD Symptom Scale-Self-report (PSS-SR)), and depression (Montgomery Asberg Depression Rating Scale). Patients also reported their subjective level of disability (Sheehan Disability Scale). Over-reporting of symptom severity was assessed using six validity items embedded within the PSS-SR. Results indicated that on average PTSD patients manifested mild impairments on the functional capacity measure, performing about 1/3 standard deviation below healthy norms, and similar performance on the MCCB. Both clinician-rated and self-rated PTSD symptom severity correlated with self-reported disability but not with functional capacity. Self-reported disability did not correlate with functional capacity or cognition. Greater self-reported disability, depression, and PTSD symptoms all correlated with higher scores on the PSS-SR validity scale. The divergence between objective and subjective measures of disability suggests that individuals' distress, as indexed by symptom validity measures, may be impacting self-reports of disability. Future studies of disability should incorporate objective measures in order to obtain a broad perspective on functioning.

Intrusive trauma recollections is associated with impairment of interference inhibition and psychomotor speed in PTSD

BACKGROUND

Intrusive cognitions that enter consciousness involuntarily are prominent symptoms of posttraumatic stress disorder (PTSD). The present study aimed to identify neuropsychological mechanisms involved.

METHOD

Fifty PTSD outpatients and 50 healthy controls were tested using Finger Tapping, Simple and Choice Reaction Times and Stroop Tasks, to measure motor, psychomotor speed, response selection, and interference inhibition ability respectively.

RESULTS

PTSD patients performed poorly in all tests, presumably owing to their generalized slowness of information processing and motor reaction. Psychomotor speed was a predictor of slowness and high error rate during the Stroop. Impaired inhibition, as measured by the interference index of the Stroop task, explained 9.7% of the predicated variance in frequency of re-experiencing PTSD symptoms and 23.5% of the predicated variance in augmentation of the interference response time.

CONCLUSION

Impaired interference control may be related to internal (re-experiencing) and external (sensory) stimuli that leads to cognitive deficits in PTSD patients.