Higher self-reported posttraumatic stress symptoms are associated with poorer working memory in active-duty service members.

OBJECTIVE: Posttraumatic stress is a significant issue facing military service members and can negatively impact working memory (WM), which is critical for performance success. Yet, few studies have examined the link between self-reported posttraumatic stress symptoms (PTSS) and WM performance in active-duty military cohorts. The present study utilized hierarchical linear modeling to examine this relationship by considering PTSS and underlying symptom clusters as well as WM demands related to load and affective interference in an active-duty military cohort (N = 515). METHOD: PTSS severity was assessed via the posttraumatic stress disorder checklist-military version (PCL-M), and behavioral performance was measured on a delayed-recognition WM task that manipulated mnemonic load (low vs. high load) and affective interference (negative combat-related vs. neutral civilian images presented during the delay interval). RESULTS: Examination of the relationship between PCL-M and WM performance demonstrated that higher total PCL-M scores (especially higher numbing and hyperarousal symptoms) were associated with poorer WM task performance, b = -0.083, p = .003, 95% CI [-0.137, -0.029], even after controlling for combat experiences and previous deployment status. This relationship was stronger on trials with negative, b = -0.114, p < .001, 95% CI [-0.175, -0.054], compared to neutral distracters, b = -0.052, p = .093, 95% CI [-0.112, 0.009]. CONCLUSIONS: These results suggest that PTSS are associated with performance costs on a WM task with combat-related negative distracters. Broadly, these findings highlight the need to address PTSS in active-duty cohorts and further investigate vulnerabilities related to cognitive demands and psychological health. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Modeling neural and self-reported factors of affective distress in the relationship between pain and working memory in healthy individuals.

The relationship between pain and cognition has primarily been investigated in patients with chronic pain and healthy participants undergoing experimental pain. Recently, there has been interest in understanding the disruptive effects of non-experimental pain in otherwise healthy individuals. Recent studies suggest that healthy individuals reporting pain also demonstrate decrements in working memory (WM) performance, however factors contributing to this relationship remain poorly understood. The present study examined the association between pain and WM in a large community-based sample of healthy individuals and investigated whether self-reported affective distress and medial frontal cortex activity might help to explain this relationship. To address these research questions, a large publicly available dataset from the Human Connectome Project (N = 416) was sourced and structural equation modeling was utilized to examine relationships between pain intensity experienced over the past 7 days, self-reported affective distress, performance on a WM (n-back) task, and task-related activation in the medial frontal cortex. Examining participants who reported non-zero pain intensity in the past 7 days (n = 228), we found a direct negative association between pain intensity and performance on the WM n-back task, consistent with prior findings. Self-reported affective distress was not associated with WM performance. Additionally, pain intensity was indirectly associated with WM performance via WM task-related activity in the ventromedial prefrontal cortex (vmPFC). Our findings suggest that pain experienced in everyday life by otherwise healthy individuals may directly impact WM performance. Furthermore, WM task-related increases in vmPFC activity may be a factor contributing to this relationship.

Experience sampling of the degree of mind wandering distinguishes hidden attentional states.

Experience sampling of attentional states has consistently demonstrated that mind wandering is a frequent and disruptive obstacle when one must sustain attention during continuous task performance. Yet, methods commonly used to assess the subjective experience of mind wandering may conflate several potential sources of meaningful variation in individuals' degree of task engagement. In the present study, we examined evidence for distinct and identifiable patterns in subjective reports of the degree of task-related attentional focus during a sustained attention task in a large sample of adults (N = 537). Experience sampling probes embedded in the task assessed task-related focus using a continuum of response ratings ranging from 1 (on-task) to 6 (off-task). Participants used a range of probe response options in categorizing their current attentional state, and the continuum of probe ratings differentiated patterns of behavioral performance in the moments preceding probes. Markov-chain modeling of the categorical time series sequence of probe ratings further revealed distinct and behaviorally relevant hidden states underlying probe rating behavior. We replicated these findings in two additional independent data sets. Collectively, these findings suggest that three or more hidden attentional states best account for subjective ratings of task-related focus. The implications of these findings for models of sustained attention and mind wandering are discussed.

Memory load, distracter interference, and dynamic adjustments in cognitive control influence working memory performance across the lifespan.

Capacity-limited working memory (WM) systems have been known to degrade in older age. In line with inhibition-deficit theories of aging, WM deficits in older individuals have been attributed to failures in the ability to suppress the processing of task irrelevant, distracting information. Yet, other cognitive mechanisms underlying age-related WM deficits have been observed, including failures in WM with increasing memory load. Moreover, both distracting information and high memory load have been shown to trigger adjustments in cognitive control leading to subsequent performance benefits on later trials. However, no studies have characterized these dynamic adjustments across the life span or examined their contribution to WM deficits in older adults. We investigated the contribution of distracter interference, memory load, and dynamic adjustments in cognitive control on WM performance in 505 individuals with ages ranging from adolescence to older adulthood. Distracter interference and memory load were parametrically manipulated (high vs. low) in a delayed-recognition WM task, and accuracy was examined as a function of current (N) and previous (N-1) trial demands. Curvilinear models revealed that performance differs over the life span depending on specific WM task demands. Specifically, the ability to suppress task irrelevant distracters was greater in adulthood compared with adolescence, but worse in later life. In contrast, memory load resulted in performance deficits with increasing age, which were exacerbated when high load and interference demands combined. Dynamic adjustments in cognitive control was spared, in part, with memory-load triggered sequential trial effects maintained across the life span, but interference-triggered benefits observable up to middle age. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Does mindfulness training help working memory 'work' better?

There has been a proliferation of mindfulness training (MT) programs offered across a multitude of settings, including military, business, sports, education, and medicine. As such, ascertaining training effectiveness and determining best practices for program delivery are of the utmost importance. MT is often introduced to promote an array of desired effects from better mood, better leadership and management skills, to improved workplace or academic performance. Despite the diversity of factors motivating adoption of MTs, it can be argued from a cognitive training perspective that there should be uniformity in the core cognitive processes strengthened via repeated and systematic engagement in MT exercises. Herein, we explore the hypothesis that MT promotes salutary changes in the brain's working memory (WM) system. We review prior research and highlight aspects of MT programs that may be critical for achieving beneficial WM effects. Further, we suggest that given the centrality of WM in core processes such as emotion regulation, problem solving, and learning, MT programs capable of achieving WM benefits may be best positioned to promote other desired outcomes (e.g. reductions in negative mood). For these reasons, we recommend that more studies include WM metrics in their evaluation of MT programs.

Prevalence and clinical correlates of explosive outbursts in Tourette syndrome.

The aim of this study was to examine the prevalence and clinical correlates of explosive outbursts in two large samples of individuals with Tourette syndrome (TS), including one collected primarily from non-clinical sources. Participants included 218 TS-affected individuals who were part of a genetic study (N=104 from Costa Rica (CR) and N=114 from the US). The relationships between explosive outbursts and comorbid attention deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder (OCD), tic severity, and prenatal and perinatal complications were examined using regression analyses. Twenty percent of participants had explosive outbursts, with no significant differences in prevalence between the CR (non-clinical) and the US (primarily clinical) samples. In the overall sample, ADHD, greater tic severity, and lower age of tic onset were strongly associated with explosive outbursts. ADHD, prenatal exposure to tobacco, and male gender were significantly associated with explosive outbursts in the US sample. Lower age of onset and greater severity of tics were significantly associated with explosive outbursts in the CR sample. This study confirms previous studies that suggest that clinically significant explosive outbursts are common in TS and associated with ADHD and tic severity. An additional potential risk factor, prenatal exposure to tobacco, was also identified.