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The relationship between physical activity (PA) intensity and executive functions in older adolescents remain poorly understood. This study aimed to examine the associations between PA intensity, volume, attentional control, and working memory, and the moderating effects of sex, in older adolescents.We analyzed baseline data from 418 participants (211 females, MAfter controlling for AvACC, sex moderated the relationships between IG, and incongruent SDRT (B = 0.53, 95% CI: 0.12, 0.94) and CVRT (B = 0.63, 95% CI: 0.22, 1.05; Ps ≤ 0.002). Only girls with higher IG showed smaller incongruent SDRT and CVRT (Bs ≤ -0.26, Ps ≤ 0.01). IG was not related to working memory. AvACC and MVPA were not related to attentional control or working memory.Our findings reveal a novel association between higher-intensity PA and superior attentional control among adolescent girls.

Highlights • Brief vigorous physical activity bouts benefited cognitive processing speed. • Bouted physical activity was specifically related to neurofunctional measures. • The number of associations increased with physical activity intensity. • Observed associations largely did not vary with accelerometer epoch length., Graphical abstract Image, graphical abstract, Background Structured vigorous physical activity (VPA) can improve cognitive control in children, but studies relating daily physical activity (PA) to cognitive control have yielded conflicting findings. While objectively measured daily PA summarizes all occurrences of PA within a registered period, a minimum duration of continuous PA is required for registration of a PA bout. Because brief bouts of high-intensity PA can account for a large proportion of children's daily activity-related energy expenditure, this study assessed whether daily and bouted VPA were selectively related to cognitive control in preadolescents relative to other PA intensities. Methods A total of 75 children between the ages of 8 and 10 years (49% girls) wore an ActiGraph wGT3X+ on the hip for 7 days. The acceleration signal from the vertical axis was summarized over 1 s, 5 s, and 15 s epochs. Daily and bouted moderate PA, moderate-to-vigorous PA, and VPA were measured. PA bouts were expressed as the frequency and time spent in 2 different continuous PA bouts, one lasting ≥10 s and the other lasting ≥30 s at a given intensity. Inhibitory control was assessed using behavioral responses to a modified flanker task (mean reaction time (RTmean) and accuracy). Attentional resource allocation and cognitive processing speed were measured using the amplitude and latency of the P3 component of event-related brain potentials, respectively. Associations between PA, behavioral indices of inhibitory control, P3 amplitude, and latency were assessed using hierarchical regression models. Results Daily VPA was not related to RTmean or accuracy on either congruent or incongruent trials. In contrast, more time spent in VPA bouts lasting ≥30 s predicted shorter P3 latency across epochs and flanker congruencies (all β ≤ –0.24, all p ≤ 0.04). The associations between shorter P3 latency and the time spent in moderate-to-vigorous PA bouts lasting ≥30 s were less consistent and largely limited to congruent trials (congruent: β (–0.31, –0.34)). No significant associations were observed upon correction for false discovery rate. Conclusion The pattern of uncorrected associations aligns with the dose–response literature and suggests that brief VPA bouts may yield the greatest benefits to cognitive processing speed in preadolescents. Future studies using measures of brain structure and function are needed to understand the mechanisms linking bouted VPA to neurocognitive function during childhood.

Individual differences in brain network modularity at baseline can predict improvements in cognitive performance after cognitive and physical interventions. The present study is the first to explore whether brain network modularity predicts changes in cortical brain structure in 8- to 9-year-old children involved in an after-school physical activity intervention (N=62), relative to children randomized to a wait-list control group (N=53). For children involved in the physical activity intervention, brain network modularity at baseline predicted greater decreases in cortical thickness in the anterior frontal cortex and parahippocampus. Further, for children involved in the physical activity intervention, greater decrease in cortical thickness was associated with improvements in cognitive efficiency. The relationships among baseline modularity, changes in cortical thickness, and changes in cognitive performance were not present in the wait-list control group. Our exploratory study has promising implications for the understanding of brain network modularity as a biomarker of intervention-related improvements with physical activity.

Excessive sedentariness has been related to poorer cognitive control in adults. Sedentariness may compound obesity-related impairments in response inhibition, but its relationship to response inhibition remains poorly understood. This study investigated the relationship between accelerometer-measured sedentary time (ST, min/day), performance on the Oddball and NoGo tasks, N2 and P3-ERP indices of response inhibition and attentional control in 80 adults with overweight and obesity (55 females, Mage = 35.2 ± 5.8 years, BMI = 32.8 ± 5.3 kg/m2 ). ST was not related to performance on the Oddball task. However, more sedentary adults had larger P3b amplitude to targets. Higher ST was also related to increased attentional resource allocation during NoGo target and nontarget trials as indicated by higher P3b amplitudes across centroparietal sites (C1, Cz, C2, CP1, CPz, CP2; ps ≤ .03). ST was negatively indirectly related to target accuracy on NoGo trials through its association with faster response times to nontargets (95% percentile bootstrap CI for a standardized effect: -0.182, -0.014). ST was not related to N2 amplitude on either Oddball or NoGo target trials. Adjustment for moderate-to-vigorous physical activity (MVPA; all models), age (models with P3b NoGo target amplitude, N2 NoGo target amplitude and latency), and % fat mass (models with target NoGo accuracy and N2 NoGo target amplitude) did not modulate behavioral findings. MVPA did not significantly predict P3b amplitude. Our results suggest suboptimal response inhibition due to trading accuracy for speed and despite the upregulation of attentional resources among more sedentary adults with overweight and obesity.

Sedentary behavior increases the risk for multiple chronic diseases, early mortality, and accelerated cognitive decline in older adults. Interventions to reduce sedentary behavior among older adults are needed to improve health outcomes and reduce the burden on healthcare systems. We designed a randomized controlled trial that uses a self-affirmation manipulation and gain-framed health messaging to effectively reduce sedentary behavior in older adults. This message-based intervention lasts 6 weeks, recruiting 80 healthy but sedentary older adults from the community, between the ages of 60 and 95 years. Participants are randomly assigned to one of two groups: 1) an intervention group, which receives self-affirmation followed by gain-framed health messages daily or 2) a control group, which receives daily loss-framed health messages only. Objective physical activity engagement is measured by accelerometers. Accelerometers are deployed a week before, during, and the last week of intervention to examine potential changes in sedentary time and physical activity engagement. Participants undertake structural and functional (resting and task-based) MRI scans, neuropsychological tests, computerized behavioral measures, and neurobehavioral inventories at baseline and after the intervention. A 3-month follow-up assesses the long-term maintenance of any engendered behaviors from the intervention period. This study will assess the effectiveness of a novel behavioral intervention at reducing sedentarism in older adults and examine the neurobehavioral mechanisms underlying any such changes.

Background There is an increasing prevalence of physical inactivity during childhood, concurrent with a rise in obesity rates, which is associated with a variety of health problems. However, the extent to which increased body mass index (BMI) influences acute physical activity (PA) benefits on cognition in childhood remains unknown. The aim of this study was to examine whether BMI influences the effects of acute PA on inhibitory control task performance. Methods In a sample of 116 children pooled from four prior studies (ages 8-11; 51 females), demographic measures of age, sex, IQ, socioeconomic status, and aerobic fitness were considered along with BMI. Children participated in a counterbalanced, randomized crossover study, whereby they completed two different interventions; 20 minutes of treadmill walking (60-70% heart rate max) and restful reading (non-exercise control). Following each intervention, children performed a modified flanker task that manipulates inhibitory control demands. Correlations were conducted to determine the influence of demographic variables, fitness, and BMI on inhibitory control following each intervention. Subsequent hierarchical regression analyses were performed with significant demographic factors in the first step, aerobic fitness in the second step when significant, and BMI in the final step. Results Analyses indicated that children exhibited improved task performance (p's ≤ 0.001) and decreased interference (p = 0.04) following the walking intervention compared to the restful reading control condition, indicating greater benefits following acute PA across task condition, with selectively greater benefits for the task condition requiring greater inhibitory control. Regression analyses revealed that greater BMI was related to decreased performance following acute PA (p = 0.001); an association not observed following restful reading (p's ≥ 0.11). These results suggest that BMI negatively influences the effect of acute exercise on performance. Conclusion Confirming previous studies, these findings indicate beneficial effects of acute PA on a flanker task that modulates inhibitory control requirements, but the effects are significantly greater for task conditions requiring greater amounts of inhibitory control. Further, these beneficial effects of PA appear to be blunted in children with higher BMI. These findings suggest that the acute benefits of PA on cognition may not be fully realized in children with higher BMI.

To assess the relationships between daily sedentary time (ST), prolonged ST, moderate-to-vigorous physical activity (MVPA), and behavioral and neuroelectric indices of cognitive control in adults with overweight and obesity (OW/OB). A cross-sectional design was used. Overall, 89 adults (BMI = 31.9 ± 4.9 kg/m2) provided measures of ST, prolonged ST (i.e., ST accumulated in ≥20 min), and MVPA from a hip-worn accelerometer worn over 7 days. Inhibitory control was measured with a modified Eriksen flanker task and cognitive flexibility with task switching. The amplitude and the latency of the P3 component of event-related potentials during each task were used as measures of attentional resource allocation and information processing speed, respectively. After adjusting for ST and MVPA, prolonged ST was related to greater interference (i.e., a larger decrement in accuracy between congruent and incongruent trials of the flanker task) indicative of a specific relationship between prolonged ST and poorer inhibitory control. Before adjusting for ST, MVPA was related to a smaller Global Switch Cost expressed as larger (more positive) amplitude of the P3 difference wave (mixed-task minus single-task condition of the switch task). Adjustment for ST attenuated this association to non-significance. Our findings suggest that future interventions focused on improving inhibitory control in adults with OW/OB should target restructuring ST in addition to current efforts to increase MVPA.

Experimental research suggests that sport-related concussion can lead to persistent alterations in children's neurophysiology and cognition. However, the search for neuropsychological tests with a similar ability to detect long-term deficits continues.The current study assessed whether a target battery of neuropsychological measures of higher cognition and academic achievement would detect lingering deficits in children 2 years after injury.Cross-sectional.A total of 32 pre-adolescent children (16 concussion history, 16 control) completed a targeted battery of neuropsychological and academic tests.Children with a history of concussion exhibited selective deficits during the Raven's Coloured Progressive Matrices, Comprehensive Trail-Making Test, and the mathematics sub-section of the WRAT-3. Deficit magnitude was significantly related to age at injury, but not time since injury.The current results suggest that neuropsychological measures of higher cognition and academic achievement may be sensitive to lingering deficits, and that children injured earlier in life may exhibit worse neuropsychological and academic performance.

The aim of this study was to reanalyze several datasets to investigate the relation of childhood aerobic fitness on cognition via a number of task performance outcomes and the P3 event-related brain potential component during a modified flanker task, which modulates inhibitory control demands. In a sample of 702 preadolescent children (ages 8–11; 342 females), demographic measures of age, sex, IQ, socioeconomic status, and pubertal status were considered along with aerobic fitness (i.e., VO2peak%). Correlational analyses were conducted to determine the influence of the demographic variables and aerobic fitness on inhibitory control outcomes of response accuracy, reaction time (RT), response variability, interference control, cognitive strategies, P3 amplitude, and P3 latency. Subsequent hierarchical regression analyses were performed with significant demographic factors in the first step and aerobic fitness in the final step. Results indicated that after accounting for significant demographic variables specific to each dependent outcome, aerobic fitness was positively related to response accuracy, with no such relations observed for response speed (RT) for congruent and incongruent conditions of the flanker task. However, greater aerobic fitness was associated with less RT variability and lower accuracy interference. In terms of cognitive strategies, greater fitness was also associated with better discrimination accuracy as well as faster and better quality of information uptake. Across a 15-site region of interest around the topographic maximum, findings indicated that aerobic fitness was positively associated with larger P3 amplitude during incongruent trials. No such relation was observed for P3 latency. Relying on a large aggregated dataset, we demonstrated that aerobic fitness may be particularly beneficial to the allocation of attentional resources, as indexed by P3 amplitude as well as response accuracy and intraindividual variability. These findings, while generalized across inhibitory control demands, were especially related to trials that required greater amounts of inhibition. Thus, aerobic fitness may benefit brain and behavioral outcomes during childhood and has public health implications for the role of childhood physical activity on aspects of cognition that underlie scholastic performance and lifelong effective functioning.

How daily physical activity and sedentary time relate to human judgement and functional connectivity (FC) patterns that support them remains underexplored. We investigated the relationships between accelerometer-measured moderate-to-vigorous physical activity (MVPA) and sedentary time to decision-making competence (DMC) in young adults using a comprehensive Adult-Decision Making Competence battery. We applied graph theory measures of global and local efficiency to test the mediating effects of FC in cognitively salient brain networks (fronto-parietal; dorsal attention, DAN; ventral attention; and default mode), assessed from the resting-state fMRI. Sedentary time was related to lower susceptibility to a framing bias. However, once global and local efficiency of the DAN were considered we observed (1) higher susceptibility to framing with more sedentary time, mediated through lower local and global efficiency in the DAN, and (2) lower susceptibility to framing with more sedentary time. MVPA was not related to DMC or graph theory measures. These results suggest that remaining sedentary may reduce neurofunctional readiness for top-down control and decrease engagement of deliberate thought, required to ignore irrelevant aspects of a problem. The positive effect suggests that the relationship between sedentary time and DMC may be moderated by unmeasured factors such as the type of sedentary behavior.

The aim of this investigation was to examine the influence of pediatric sport-related concussion on brain and cognitive function. To do so, we used a between-participants design, measures of executive control, and event-related potentials (ERPs). The findings demonstrate that children with a history of concussion exhibit behavioral deficits in attention, working memory and impulse control, as well as neuroelectric alterations in ERP indices of visual attention (N1), conflict resolution (N2) and attentional resource allocation (P3). Furthermore, the age at injury related to the magnitude of several concussion-related deficits. Accordingly, a single sports-related concussive incident during childhood (m = 2.1 years prior to testing) may lead to subtle, yet pervasive alterations in the behavioral and neural indices of attention and executive control, and age at injury may moderate injury outcomes.

This study investigated the influence of concussion history on children's neurocognitive processing. Thirty-two children ages 8–10 years (16 with a concussion history, 16 controls) completed compatible and incompatible conditions of a flanker task while behavioral and neuroelectric data were collected. Relative to controls, children with a concussion history exhibited alterations in the sequential congruency effect, committed more omission errors, and exhibited decreased post-error accuracy. Children with a concussion history exhibited longer N2 latency across task conditions, increased N2 amplitude during the incompatible condition of the task, and decreased P3b amplitude across task conditions. Children with a history of concussion also exhibited decreased ERN and Pe amplitudes, with group difference increasing for the incompatible condition of the task. The current results indicate that pediatric concussion may lead to subtle, but pervasive deficits in attention and cognitive control. These results serve to inform a poorly understood but significant public health concern.

[This corrects the article DOI: 10.1371/journal.pone.0192533.].

The aim of this study was to assess the relations of daily moderate-to-vigorous physical activity (MVPA) to cognitive functions in 15-year-old adolescents from the Avon Longitudinal Study of Parents and Children while controlling for aerobic fitness. A sub-sample of 667 adolescents (M age = 15.4 ± 0.16 years; 55 % females) who provided valid data on variables of interest, were used in the analyses. MVPA was objectively assessed using an Actigraph GT1M accelerometer and aerobic fitness was expressed as physical work capacity at the heart rate of 170 beats per minute from a cycle ergometer test. A computerized stop-signal task was used to measure mean reaction time (RT) and standard deviation of RT, as indicators of cognitive processing speed and variability during an attention and inhibitory control task. MVPA was not significantly related to cognitive processing speed or variability of cognitive performance in hierarchical linear regression models. In simple regression models, aerobic fitness was negatively related to mean RT on the simple go condition. Our results suggest that aerobic fitness, but not MVPA, was associated with cognitive processing speed under less cognitively demanding task conditions. The results thus indicate a potential global effect of aerobic fitness on cognitive functions in adolescents but this may differ depending on the specific task characteristics.

Using a Biocultural Model of Maturity-Associated Variance in physical activity (PA) as a conceptual framework, the main and interactive effects of biological maturity status and perceived peer acceptance on PA and health-related quality of life (HRQoL) in adolescent girls were examined.Three hundred forty-two female British students in years 7 to 9 (13.2±0.83 years) participated in the study. All participants completed the PA Questionnaire for Adolescents and KIDSCREEN-10, a measure of HRQoL. Self-reported perceptions of peer acceptance were measured by items from the National Longitudinal Study of Adolescent Health.Maturity status was estimated as the percentage of predicted adult (mature) height attained at the time of observation.Analysis of covariance suggested an influence of peer acceptance on maturity-associated differences in PA, but not on HRQoL. Girls early and "on time" in maturation with higher perceptions of peer acceptance reported greater involvement in PA than girls early and "on time" in maturation with lower perceptions of peer acceptance. A reverse association was observed for late-maturing girls.Peer acceptance is an important moderator of maturity-associated variation in PA.

A model for adolescent involvement in physical activity (PA) that incorporates individual differences in biological maturation is presented. The biocultural model of maturity-associated variance in physical activity recognizes PA as a complex and multifaceted behaviour that exists in multiple contexts (e.g., transport, vocation, sport, exercise) and can be viewed from multiple perspectives (e.g., energy expenditure, movement counts, performance outcomes, fitness). The model holds that biological maturation can exert both direct and indirect effects on PA during adolescence. Direct effects imply a direct and unmediated effect of individual differences in maturation on PA. Indirect effects imply influences of individual differences in maturation on PA that are mediated by psychological constructs (e.g., self-perceptions, beliefs) and/or are moderated by exogenous factors (e.g., social interaction, culture) associated with pubertal maturation.

1 min -1 ). Fat-free mass, body surface area and stature are also used as denominators. However, issues related to the validity of estimates of fat free mass and body surface area need to be considered if these variables are used as denominators. For example, 54% and 52% of the variance in anaerobic mean and peak power obtained with the Wingate test (WAnT) was predicted by biological maturation, body mass and leg length in Portuguese adolescent basketball players aged 14-16 years. Biological maturation was expressed as the ratio of skeletal age (SA) to chronological age (CA) (1). The WAnT performance is often reported in Watt per unit of body mass or per unit of thigh volume. Ratio standards, isometry and elastic similarity Simple ratio standards (mL kg -1 min -1 ; W kg -1 ; W L -1 ) have been strongly criticised (2,3). Expressing functions relative to anthropometric dimensions is meant to control for inter-individual variability in body size and is based on the assumption of geometric similarity. The ratios rely on the assumption that variables expressed as the ratio are linearly related, but the assumption can be erroneous. Although ratio standards are commonly used to control for the effects of body size on performance, other methods provide plausible alternatives. Relationships among length, surface area and volume have implications for metabolism and thermoregulation. All linear anthropometric dimensions of the body, such as stature, segment lengths, and breadths have the dimension d. All areas including body surface area and muscle cross-sectional areas have the dimension d 2 . Total body volume given by air displacement plethysmography and other volumes (lung, heart, lower limb) have the dimension d 3

Transient epileptic amnesia is a form of temporal lobe epilepsy in which sufferers often complain of irretrievable loss of remote memories. We used a broad range of memory tests to clarify the extent and nature of the remote memory deficits in patients with transient epileptic amnesia. Performance on standard tests of anterograde memory was normal. In contrast, there was a severe impairment of memory for autobiographical events extending across the entire lifespan, providing evidence for the occurrence of 'focal retrograde amnesia' in transient epileptic amnesia. There was a milder impairment of personal semantic memory, most pronounced for midlife years. There were limited deficits of public semantic memory for recent decades. These results may reflect subtle structural pathology in the medial temporal lobes or the effects of the propagation of epileptiform activity through the network of brain regions responsible for long-term memory, or a combination of these two mechanisms. © The Author (2010). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved.

Introduction Despite the rising prevalence of stroke, no comprehensive model of postacute stroke care exists. Research on stroke has focused on acute care and early supported discharge, with less attention dedicated to longer term support in the community. Likewise, relatively little research has focused on long-term support for informal carers. This review aims to synthesise and appraise extant qualitative evidence on: (1) long-term healthcare needs of stroke survivors and informal carers, and (2) their experiences of primary care and community health services. The review will inform the development of a primary care model for stroke survivors and informal carers. Methods and analysis We will systematically search 4 databases: MEDLINE, EMBASE, PsycINFO and CINAHL for published qualitative evidence on the needs and experiences of stroke survivors and informal carers of postacute care delivered by primary care and community health services. Additional searches of reference lists and citation indices will be conducted. The quality of articles will be assessed by 2 independent reviewers using a Critical Appraisal Skills Programme (CASP) checklist. Disagreements will be resolved through discussion or third party adjudication. Meta-ethnography will be used to synthesise the literature based on first-order, second-order and third-order constructs. We will construct a theoretical model of stroke survivors’ and informal carers’ experiences of primary care and community health services. Ethics and dissemination The results of the systematic review will be disseminated via publication in a peer-reviewed journal and presented at a relevant conference. The study does not require ethical approval as no patient identifiable data will be used.

Aims: Transient epileptic amnesia (TEA) is a recently recognised form of temporal lobe epilepsy in which sufferers often complain of irretrievable loss of remote memories. We aimed to answer the following questions: 1) What is the extent and nature of the autobiographical memory loss? 2) Is there impairment of personal semantic and public semantic memory? 3) Is there evidence for focal retrograde amnesia? Methods: 14 patients with TEA and 12 matched controls participated. We used a broad range of standard anterograde and remote memory tests to clarify the extent and nature of the remote memory deficits. In particular, we used the Autobiographical Interview (AI), which provides a more sensitive measure of autobiographical memory than previous instruments, together with tests measuring personal semantic and public semantic memory. Results: Performance on standard tests of anterograde memory was normal. In contrast, there was a severe impairment of memory for autobiographical events, extending across the entire lifespan, providing evidence for the occurrence of “focal retrograde amnesia” in TEA. There was a milder impairment of personal semantic memory, most pronounced for midlife years. There were minor deficits of public semantic memory for recent decades. Conclusions: These results may reflect subtle structural pathology in the medial temporal lobes or the effects of the propagation of epileptiform activity through the network of brain regions responsible for long-term memory.