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911.
概念规律如记忆项间的类别关系如何影响视觉工作记忆容量是一个有争议的问题。针对该问题, 学界存在两种预测截然不同的假说:(1)混合类别优势假说, (2)同类别优势假说。综述文献发现, 该类研究均采用带有细节特征的真实客体作为实验材料, 因此前人研究中发现的混合类别优势效应或同类别优势效应中必然混有低水平知觉特征的影响。故本研究采用去除细节信息的动物剪影作为记忆材料来排除上述因素的影响, 旨在厘清上述两种假设, 并采用对侧延迟活动作为神经指标, 来进一步探讨概念规律影响工作记忆容量的内在机制。两个行为实验发现, 不论记忆项同时呈现还是序列呈现, 均存在同类别记忆优势效应。脑电实验结果发现相比记忆不同类别客体, 记忆同等数量的同类别客体诱发的对侧延迟活动的幅值更小。上述结果一致表明, 视觉工作记忆可借助概念的方式将同类别客体加以组织, 从而有效扩大视觉工作记忆容量, 支持了同类别优势假说。  相似文献   
912.
School recess can provide social, emotional, and physical benefits for children. Yet, not all children experience recess the same, as inequity in access to recess and variability in the quality of recess exist. Researchers have yet to understand the long-term implications of recess experiences on adult well-being and physical activity behaviors. The purpose of this study was to explore the inter-relationships between memories of recess, physical activity, and social-emotional well-being. A total of 514 adults between the ages of 19 and 79 (M = 45.56; SD = 15.62) were surveyed via Prolific, a web-based research platform. Participants were asked about their memories of recess enjoyment and recess exclusion, and current physical activity levels, physical activity enjoyment, social isolation, social role satisfaction, and sense of meaning and purpose. Structural equation modeling analysis showed that memories of recess enjoyment were associated with meaning and purpose (β = 0.138, p < .05) and PA enjoyment (β = 0.183, p < .05). Furthermore, retrospective recess exclusion predicted current social isolation (β = 0.266, p < .05) and was negatively associated with retrospective recess enjoyment (β = −0.379, p < .05). Findings highlight the importance of childhood recess experiences and its impact on current physical activity behaviors, social isolation, and meaning and purpose later in life. Consistent with other research, early positive physical activity experiences, in the form of recess, appear to provide more assurances that one will engage in healthier lifestyle behaviors and more favorable psycho-socio-emotional profiles in adulthood.  相似文献   
913.
ObjectiveRheumatoid arthritis (RA) is an autoimmune disease, characterised by high-grade systemic inflammation, pain, and swollen joints. RA patients have an increased risk for cardiovascular disease (CVD). This study examined if a 3-month individualised RA-tailored exercise programme with one-on-one Self-Determination Theory (SDT)-based support for physical activity (PA) facilitated autonomous motivation, increased PA behaviour, and induced greater improvements in cardiovascular and RA-related disease characteristics, and wellbeing in RA, compared to a standard provision tailored exercise programme.Methods115 RA patients were randomised into either the SDT-based psychological intervention + exercise programme (experimental group) or an exercise programme only (control group). Cardiorespiratory fitness (primary outcome), self-reported PA, disease characteristics, CVD risk, wellbeing, and SDT constructs were assessed at baseline (pre-intervention), 3 months (post-intervention), 6 months, and 12 months follow-up. Mixed linear modeling was used to examine within- and between participant changes in these outcome measures.ResultsIn 88 patients with complete baseline data, cardiorespiratory fitness did not change from baseline to 3-, 6- or 12 months in either group. CVD risk, disease characteristics, wellbeing, and need satisfaction did not change, with the exception of diastolic blood pressure. Significant group by time interaction effects were found for functional ability (6- & 12-months), CVD risk (6-months) and PA (3-months). Autonomous motivation increased and controlled motivation decreased more in the experimental group compared to the control group at 3 months.ConclusionsDespite improving quality of motivation for exercise, no changes in cardiorespiratory fitness or other psychological and physiological health outcomes were found. This suggests more intensive support is needed when initiating an exercise programme to achieve health benefits in RA.  相似文献   
914.
ObjectivesThe role of physical activity (PA) in the promotion of mental wellbeing and prevention of psychological disorders in population groups at increased risk for mental health conditions, such as migrant populations, has never been systematically investigated.MethodsWe conducted a systematic review and meta-analysis according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), Pubmed, Web of Science, SportDiscus. We included randomized (RCTs), controlled clinical trials (CCT), and pre-post intervention studies, that assessed the efficacy of PA interventions in migrants, compared with any types of controls.ResultsWe included 27 studies (4166 participants) (16 RCTs; 2 CCTs; 9 pre-post design) between 1997 and 2020. Meta-analysis showed a significant beneficial effect of PA over control conditions for general functioning (SMD -0.35, 95% CI -0.83 to −0.16; 400 participants), outcome expectancies (SMD -0.78, 95% CI -1.17 to −0.40; 118 participants), self-efficacy/coping (SMD -0.28, 95% CI -0.52 to −0.03; 269 participants), and psychological symptoms (SMD -0.48, 95% CI -0.88 to −0.08; 6 RCTs; 597 participants). Similar findings were produced by pre-post intervention studies (SMD -0.35, 95% CI -0.60 to −0.10; 7 studies; 302 participants).ConclusionsMigrant populations may benefit from PA interventions to improve psychological outcomes. Uncertainty remains about the best approach to promote PA in this population, and future research should consider the complex factors that characterize the migration experience.  相似文献   
915.
The study was designed to determine associations between physical activity (PA) and affect before and during COVID-19 stay-at-home orders and how change in PA predicted change in affect during this time. Before and during COVID-19 stay-at-home orders, college students (n = 107) completed assessments of PA, positive and negative affect, sleep quality, food insecurity, and stressful life events (during stay-at-home order only). Total minutes of PA was positively associated with positive affect before (B = 0.01, p < 0.01) and during (B = 0.01, p = 0.01) COVID-19 stay-at-home orders. Change in minutes of PA was positively associated with change in positive affect (B = 0.01, p = 0.01). Associations between PA and positive affect were not moderated by stressful life events. PA only predicted negative affect before COVID-19 stay-at-home orders (B = −0.003, p = 0.04). PA appears to enhance positive affect during a global pandemic. Findings have implications for PA as a tool for maintaining or enhancing mental health during a time of trauma and uncertainty.  相似文献   
916.
917.
Chronic and acute stress may have a detrimental effect on children's physical activity. Research on stress as a predictor of children's physical activity has mostly focused on stress between children, rather than how children's within-day variation in stress may predict physical activity. The current study assessed the within- and between-effects of stress on subsequent physical activity in three different time windows using ecological momentary assessment (EMA) and accelerometry. Children (N = 190; MBaseline Age = 10.1 ± 0.9, 53% female, 56% self-identified Hispanic/Latino) completed six semi-annual assessment bursts across three years. During each burst, participants responded to up to seven (weekend) or three (weekday) randomly prompted EMA surveys on smartphones for seven days and wore a waist-worn accelerometer. Multi-level structural equation modeling examined within- and between-subjects effects of stress as a predictor of children's subsequent moderate-to-vigorous physical activity (MVPA) in the 15, 30, and 60 min following the EMA prompt. Latent variables were created for within- and between-subjects stress were comprised of three EMA stress items. Higher than average levels of stress (within-subjects) significantly predicted lower MVPA in the subsequent 15, 30 and 60 min (ps < .05). Between-subjects stress was not significantly associated with subsequent MVPA (ps > .05). Results indicate that elevated momentary stress predicts less subsequent MVPA. These findings suggest that within-day fluctuations in stress may be a barrier for children engaging in physical activity. Childhood physical activity promotion and interventions should consider the role of children's stress, aim to reduce the stress children experience throughout the day, and incorporate stress coping strategies.  相似文献   
918.
Under conditions of rapid changes in working life, there is an urgent need to examine the nature of creativity and learning in organizations. The aim of this study was to investigate the nature of self‐directed learning (SDL) practices in creative activity in technology‐based work. We focus on both individual and collective practices but also on the importance of organizational culture. The data consist of 46 interviews and observational field notes collected from participating organizations. Thematic and ethnographic analyses were utilized as tools to reveal the nature of SDL in creative activity. We found three themes describing of the nature of SDL in creative activity: a combination of individual and collective action, solving common problems through dialogue and discussions, and the organizational culture framing SDL in creative activity. Based on the findings, we provided support for that SDL in creative activity is manifested as a socio‐cultural phenomenon and SDL practices are intertwined with creative activity. We discovered organization cultural frames that can support the realization of SDL and creative activity in working life. However, more research on the relationship between these phenomena and the conditions for their realization is needed.  相似文献   
919.
Background/Objective: The aim was to evaluate the evolution of depressive symptoms and to explore the influence of physical activity (PA) practice during the home confinement due to the COVID-19 outbreak in Spain. Method: Information was collected from 595 confined participants who reported personal and contextual information, depressive symptoms and PA levels at four time points. Results: The changes in depressive symptoms were analyzed using a linear mixed model with cubic splines. Results showed a significant increase, with a significant rise between T1 and T2 (OR = 2.38, 95% CI = 1.83-3.10). It continued growing until T4 (OR = 2.93, 95% CI = 1.97-4.38). A negative relationship was observed between the increase in depressive symptoms and moderate-to-vigorous physical activity (MVPA) levels, with a significant slope up to 4 hours of MVPA per week (OR = 0.51, 95% CI = 0.29-0.90) that tended to increase until 16 hours per week of MVPA (OR = 0.41, 95% CI = 0.20-0.87). Conclusions: Results from a partition model showed that moderate intensity of PA could be enough to prevent an increase of depressive symptoms during home isolation.  相似文献   
920.
ObjectiveThe aim of this study was to compare adherence to physical activity and sedentary behaviour recommendations within the 2011 Institute of Medicine Early Childhood Obesity Prevention Policies as well as screen time recommendations from the 2013 American Academy of Pediatrics for samples of infants in child care centres in Australia, Canada, and the United States (US).MethodsThis cross-sectional study used data from: the Australian 2013 Standing Preschools (N = 9) and the 2014–2017 Early Start Baseline (N = 22) studies; the 2011 Canadian Healthy Living Habits in Pre-School Children study (N = 14); and the American 2008 (N = 31) and 2013–2017 (N = 31) Baby Nutrition and Physical Activity Self-Assessment for Child Care (NAP SACC) trials. Data were compared on the above infant recommendations. Percentages were used to describe compliance to the recommendations and chi-square tests to determine whether compliance differed by country.ResultsChild care centres were most compliant (74%–95%) with recommendations to: provide daily indoor opportunities for infants to move freely under adult supervision, daily tummy time for infants less than 6 months of age, indoor and outdoor recreation areas that encourage infants to be physically active, and discourage screen time. Centres were least compliant (38%-41%) with adhering to recommendations to: limit the use of equipment that restricts an infant’s movement and provide education about physical activity to families. Compared with Canadian and US centres, Australian centres were less compliant (46%) with the recommendation to engage with infants on the ground each day, to optimize adult-infant interactions and to limit the use of equipment that restricts the infant’s movement. Canadian centres were less compliant (39%) with the recommendation to provide training to staff and education to parents about children’s physical activity. US centres were less compliant (25%–41%) with the recommendations to provide daily opportunities for infants to explore their outdoor environment, limit the use of equipment that restricts the infant’s movement and provide education to families about children’s physical activity.ConclusionsAssisting child care centres on limiting the use of equipment that restricts an infant’s movement, and providing education about children’s physical activity to families may be important targets for future interventions.  相似文献   
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