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A study was devised to investigate the role of physical fitness in moderating both cognitive work capacity and fatigue onset under sustained combat operations. Sixteen male ROTC cadets were followed through a 2.5-day, Pre Ranger Evaluation exercise. Prior to the start of the exercise, the cadets’ overall level of physical fitness was assessed by using five fitness indices (Harvard Step Test, chin-ups, push-ups, sit-ups, and two-mile run). Cognitive performance and subjective measures of fatigue state were assessed at regular intervals before, during, and 1 day after the exercise. The results suggest that fitness may attenuate decrements in cognitive work capacity for certain tasks requiring prolonged mental effort, particularly as the cumulative effects of sleep loss and other stressors begin to mount. Similarly, the results suggest that as overall stress levels increase, fitness may have a beneficial effect in moderating fatigue rate. Fitness did not significantly enhance the recovery process with respect to cognitive work capacity, and actually appeared to hinder recovery from fatigue.  相似文献   
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Adolescence is a critical developmental period marked by an increase in risk behaviors, including nonsuicidal self‐injury (NSSI). Heightened reward‐related brain activation and relatively limited recruitment of prefrontal regions contribute to the initiation of risky behaviors in adolescence. However, neural reward processing has not been examined among adolescents who are at risk for future engagement for NSSI specifically, but who have yet to actually engage in this behavior. In the current fMRI study (N = 71), we hypothesized that altered reward processing would be associated with adolescents' thoughts of NSSI. Results showed that NSSI youth exhibited heightened activation in the bilateral putamen in response to a monetary reward. This pattern of findings suggests that heightened neural sensitivity to reward is associated with thoughts of NSSI in early adolescence. Implications for prevention are discussed.  相似文献   
284.
Shallow declines in nocturnal compared with diurnal blood pressure (BP dipping) have been associated with cardiovascular disease. In U.S. samples, Blacks demonstrate less BP dipping compared with Whites. In a sample of 60 Black and 60 White normotensive adults we examined stress, social integration (including parental status), social support, and hostility as potential mediators of the association between race and BP dipping. The effect of race on diastolic BP dipping was partially mediated by parental status. The effect of race on heart rate dipping was partially mediated by stressful life events. No psychosocial factors mediated the relation between race and systolic BP dipping. Although psychosocial factors appear to account for some of the observed racial differences in nocturnal blood pressure decline, our data suggest that these differences cannot be attributed entirely to covarying psychosocial effects.  相似文献   
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Memory &; Cognition - The recent memory impairments in Korsakoff’s (KD), Huntington’s (HD), and Alzheimer’s (SDAT) diseases are qualitatively different from one another. All...  相似文献   
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We evaluated the experimental hypothesis that an acute bout of aerobic exercise (AE) serves as a buffer to psychosocial stress responses in low to moderate physically fit women. Forty-eight (24 White, 24 Black) 25- to 40-year-old women participated in two counterbalanced experimental conditions: an attention control and a 40-min bout of AE at 70% heart rate (HR) reserve. The attention control and AE treatments were followed by (a) 30 min of quiet rest, (b) exposure to mental and interpersonal threat, and (c) 5 min of recovery. Blood pressure (BP) and HR were monitored at baseline, during the stressors, and throughout recovery. Self-reported distress was assessed before each stressor and upon completion of the recovery period. The results provided clear evidence that exercise dampens BP reactivity to psychosocial stress. Additionally, compared with the attention placebo control, AE reduced both the frequency and intensity of anxiety-related thoughts that occur in anticipation of interpersonal threat and challenge.  相似文献   
288.
Childhood internalizing problems may occur as early as preschool, tend to be stable over time, and undermine social and academic functioning. Parent emotion regulatory behaviors may contribute to child internalizing problems and may be especially important during the preschool years when parents model emotion coping and regulation for their children. Parents who feel out of control of their preschoolers’ behavior and emotional states may adopt avoidant emotion regulatory strategies. We proposed that parent depression, perceived locus of control, and experiential avoidance would be linked with internalizing symptoms in a high-risk sample of preschool-aged children. We also expected that locus of control would mediate the relationship between maternal depression, experiential avoidance, and child internalizing problems. Seventy-four urban, low-income, diverse mothers of Head Start preschool children completed rating scales measuring their own depression, locus of control, experiential avoidance, and their children’s internalizing behaviors. Correlational analyses revealed that mothers reporting higher levels of depression were more likely to report experiential avoidance, feeling out of control in their parenting role, and internalizing symptoms in their children. Hierarchical multiple regressions showed that locus of control explained additional unique variance in child internalizing problems over and above that explained by maternal depression. Locus of control mediated the relationship between maternal depression and child internalizing symptoms. The importance of considering parent locus of control and its relation to children’s internalizing symptoms is discussed as a potential target for early childhood prevention programs.  相似文献   
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