8 research outputs found
Functional cerebral changes in multiple sclerosis patients during an autobiographical memory test.
Our aim was to investigate the functional underpinnings of autobiographical memory (AM) impairment in multiple sclerosis (MS) patients. To that end, 18 patients and 18 controls underwent the autobiographical interview (AI). Subsequently, the 36 participants underwent a functional magnetic resonance imaging (fMRI) session designed to assess the construction and elaboration of AMs. A categorical control task was also presented. Patients were trained in the fMRI procedure to optimise the procedural aspects accompanying the task itself. Although the patients obtained significantly poorer AI scores (p < .001), their performance on the easier AM fMRI task was efficiently carried out, allowing relevant comparisons with healthy controls. Relatively to healthy controls, the patients showed increased and bilateral cerebral activations (p < .005) during the construction and elaboration phases. The prefrontal, temporal and posterior cerebral region activations were located within the core network sustaining AM, with the bilateral prefrontal region being centrally involved. The parametric neural responses to the difficulty of access and amount of details of memories were also significantly different for the two groups, with the right hippocampal region showing a particularly increased recruitment (p < .005). The findings suggested the presence of functional cerebral changes during AM performance and supported the presence of AM retrieval deficit in MS patients.journal articleresearch support, non-u.s. gov't20152014 09 22importe
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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
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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
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Higher self-reported posttraumatic stress symptoms are associated with poorer working memory in active-duty service members
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Does mindfulness training help working memory ‘work’ better?
•MT is conceptualized as a form of cognitive training.•Specific MT practices engage and strengthen component attentional and WM processes.•WM is important for a multitude of cognitive and affective processes.•MT-related strengthening of WM may benefit psychological health outcomes.
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
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Does Intensive Mindfulness Training Strengthen Sustained Attention? Examining Individual Differences in Mind Wandering during the Sustained Attention to Response Task
Mindfulness training (MT) has been shown to benefit sustained attention and mind wandering. Yet, few studies have examined whether benefits differ as a function of individual differences in mind wandering. The sustained attention to response task (SART) measured task accuracy (A′), response time variability (response time intraindividual coefficient of variation, ICV), and self-reported mind wandering in participants before (T1) and after (T2) a 1-month MT retreat (n = 56), as well as in a control group (n = 32) who received no MT. Only the retreat group demonstrated increased A′ and reduced mind wandering, but no change in ICV, from T1 to T2. Retreat participants demonstrated reduced ICV compared to the control group only when considering individual differences in mind wandering such that retreat participants with higher levels of mind wandering at T1 demonstrated greater benefits to ICV over time. These findings suggest MT may benefit sustained attention, as seen in changes on both objective and subjective measures, and that considering baseline individual differences may increase our understanding of MT’s benefits to sustained attention