Hyperarousal Symptoms Explain the Relationship Between Cognitive Complaints and Working Memory Performance in Veterans Seeking PTSD Treatment

Using network models to explore the associations between posttraumatic stress disorder symptoms and subjective cognitive functioning

Several studies have identified relationships between posttraumatic stress disorder (PTSD) and cognitive functioning. Here, we aimed to elucidate the nature of this relationship by investigating cross-sectional associations between subjective cognitive functioning (SCF) and 1) the PTSD sum score, 2) symptom domains, and 3) individual symptoms. We also investigated temporal stability by testing whether results replicated over a 3-year period. We estimated partial correlation networks of DSM-5 PTSD symptoms (at baseline) and SCF (at baseline and follow-up, respectively), using data from the National Health and Resilience in Veterans Study (NHRVS; N = 1484; Mdn = 65 years). The PTSD sum score was negatively associated with SCF. SCF was consistently negatively associated with the PTSD symptom domains 'marked alterations in arousal and reactivity' and 'negative alterations in cognitions and mood', and showed robust relations with the specific symptoms 'having difficulty concentrating' and 'trouble experiencing positive feelings'. Results largely replicated at the 3-year follow-up, suggesting that some PTSD symptoms both temporally precede and are statistically associated with the development or maintenance of reduced SCF. We discuss the importance of examining links between specific PTSD domains and symptoms with SCF-relations obfuscated by focusing on PTSD diagnoses or sum scores-as well as investigating mechanisms underlying these relations. Registration Number: 37069 (https://aspredicted.org/n5sw7.pdf).

Posttraumatic stress, visual working memory, and visual imagery in military personnel

Posttraumatic stress disorder (PTSD) is characterized by disruptions to cognitive functioning. Two studies were conducted to examine the relevance of military-related PTSD to two cognitive functions - visual working memory and visual imagery. Participants were military personnel who reported their PTSD diagnosis history and completed a self-administered screening tool for PTSD, the PTSD Checklist - Military Version. In Study 1, 138 personnel also completed a memory span task and a 2-back task using colored words in which Stroop interference was introduced via the semantic content of the words. In Study 2, a separate group of 211 personnel completed measures of perceived imagery vividness and spontaneous use of visual imagery. Interference effects on working memory in PTSD-diagnosed military personnel were not replicated. However, ANCOVA and structural equation modelling revealed that PTSD-intrusions were associated with poorer working memory whereas PTSD-arousal was associated with spontaneous use of visual imagery. We interpret these results as evidence that intrusive flashbacks disrupt working memory performance not by limiting memory capacity nor by interfering directly with memory functions such as inhibition, but by adding internal noise in the form of task-irrelevant memories and emotions. Visual imagery appears to be unrelated to these flashbacks but with arousal symptoms of PTSD, perhaps in the form of flashforwards about feared/anticipated threats.

The role of posttraumatic stress symptoms on memory complaints and performance in active-duty service members

OBJECTIVE

Memory complaints are the most common form of cognitive limitation reported by military service members, but prior research suggests that posttraumatic stress symptoms (PTSS) may account for the link between subjective cognitive complaints and objective cognitive performance. The mechanisms underlying this relationship are largely unknown, including whether the finding applies to memory complaints and performance, which clinical dimensions are involved, and how the association varies when memory complaints are non-credible.

METHOD

Using a sample of 196 US military service members, the present study aims to address these gaps by modeling the relationship between objective memory performance and plausible/implausible subjective memory complaints, then evaluating how the association is influenced by PTSS and clinical traits commonly found within PTSS (e.g. depression, anxiety, and somatic concerns).

RESULTS

Overall memory complaints were associated with immediate and delayed recall, but both associations were fully mediated by PTSS (95% CI -0.14, -0.01; 95% CI -0.14, -0.02, respectively). Implausible memory complaints, however, were inconsistently linked to memory performance, and no PTSS mediation was observed. Of the clinical traits, only depression moderated the impact of PTSS, specifically by influencing the link between PTSS and overall memory complaints (β = -0.02, SE = 0.004, p < .001).

CONCLUSIONS

These results corroborate the importance of assessment for PTSS and depression in service members who report subjective memory complaints and highlight how targeted intervention for these conditions may play a key role in the management of memory complaints.

The role of inhibitory processes in the relationship between subsyndromal PTSD symptoms and aggressive behaviour

The issue of aggressive behaviours among military populations is important for a number of reasons, including the potential associated occupational, social and functional impacts. Controlled aggressive behaviour is an adaptive requirement of some military roles, however, this aggression can become maladaptive when uncontrolled, or contextually inappropriate. Elevated aggression among deployed veterans has been identified in a number of studies, although the reasons for it are not well understood. Deployed populations have elevated levels of stress and trauma exposure, have higher rates of childhood and other lifetime trauma exposures and have a heightened risk for subsyndromal or full PTSD. Both trauma exposure and PTSD have been found to be associated with executive function deficits, and increased anger and aggressive behaviours. The purpose of this paper was to explore the contribution of both early PTSD symptoms and cognitive disinhibition in predicting increased aggressive behaviour following deployment in a healthy active serving cohort. After controlling for pre-deployment PTSD symptoms and cognitive function, there were significant main effects of both PTSD symptoms and cognitive function on increased aggression at post-deployment. Furthermore, the positive association between PTSD symptoms and post-deployment aggression was moderated by response inhibition deficits in the domains of false positive errors as well as faster reaction times. Subsidiary analyses showed that the effects of increased reaction time in particular increased the likelihood of PTSD symptoms being coupled with increased aggression. These findings highlight the potential effects of repeated occupational stress exposure and point to possible cognitive adaptations and long-term risk for disorder.

Improvement in executive functioning after Goal-Oriented Attentional Self-Regulation training is associated with reduction in PTSD hyperarousal symptoms among veterans with comorbid PTSD and mild TBI

Goal-Oriented Attentional Self-Regulation (GOALS) is a cognitive rehabilitation training program that combines mindfulness-based attention regulation with individualized goal management strategies to improve functioning in daily life after traumatic brain injury (TBI). While not a specific target of GOALS training, previous research has indicated improvements in emotional functioning following GOALS training, specifically symptoms related to depression and posttraumatic stress disorder (PTSD). The current study is based on the hypothesis that improvements in cognitive control processes related to executive functioning and attention after GOALS training generalize to improvements in emotional functioning, thereby resulting in reductions in emotional distress. The current study analyzed archival data from 33 Veteran participants with a confirmed diagnosis of PTSD and a history of mild TBI who received either GOALS training or a psychoeducational intervention matched for time, therapist attention, and participation format. Regression analysis was used to assess the strength of the relationship between improvements in Overall Attention/Executive Functioning and decreases in hyperarousal symptoms associated with PTSD. Results from the regression analysis revealed that improvements in Overall Attention/Executive Functioning after GOALS was significantly associated with reductions in hyperarousal symptoms associated with PTSD (R² = 0.26, F_(1,15) = 5.01, β = -.51, p < .05). The current findings suggest that cognitive improvements after GOALS training may lead to changes in emotional functioning, resulting in decreased emotional distress. This is important, particularly in VA settings, because the results potentially highlight additional areas of research and focus on the treatment of comorbid mild TBI and PTSD among Veterans.