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Adolescence is a key developmental period for developing and strengthening brain circuits that underlie effective decision-making skills, which profoundly impact lifelong health and academic, professional, and economic achievement. But decision-making skills are learned rather than inherent. School presents an ideal environment for the direct instruction and frequent practice of decision-making skills, however, finding time in the school day is a challenge for contemporary educators. We have developed a learning curriculum that involves active student participation to strengthen decision-making skills that is sufficiently flexible and adaptable to be utilized in a wide variety of content-specific classwork. Using this curriculum, students show evidence of improved decision-making skills, including increased consideration of the number of factors that are relevant to their decision, the resources needed to make a particular decision, and both the short-term and long-term consequences of decisions.

Background/objective: To examine the cognitive benefits of 6  months of prescribed intermittent exercise (10-min bouts totaling 150 weekly minutes) in community-dwelling older adults, comparing effects of low-intensity movement (LIM) and moderate-intensity aerobic exercise (aerobic exercise; AE) training; and exploring biological mechanisms of exercise-related cognitive improvement. Method: Twenty-five adults (>60  years old) participated in a 6-month controlled trial and were randomized into LIM or AE intermittent training. Cognition was assessed using a neuropsychological test battery including the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), California Verbal Learning Test, 2nd Edition (CVLT-II), and Delis-Kaplan Executive Function System (D-KEFS). Neuroimaging measures were collected using a 7  T human MRI scanner. Serologic neurotrophic and inflammatory factors were analyzed using Luminex multiplex assays [brain derived neurotrophic factor (BDNF); vascular endothelial growth factor (VEGF)]; interleukin-6 (IL-6), C-reactive protein (CRP), plasminogen activator inhibitor (PAI-1). Results: LIM and AE intermittent training had dissociable effects on cognition, with LIM resulting in improved learning and memory and AE resulting in improved executive functioning. Intervention groups differed on change in cognitive performance on CVLT-II learning and D-KEFS trail making test. Increase in right dorsolateral prefrontal cortex (DLPFC) surface area was linked to executive improvement (i.e., phonemic fluency) regardless of intervention group. A decline in circulating PAI-1 was linked to learning and memory improvement in response to LIM over 6 months. Conclusion: Moderate-intensity AE and LIM intermittent training likely have distinct cognitive benefits, though low-intensity activity is often included as a control group in exercise trials in aging. [ABSTRACT FROM AUTHOR]

Early life stress (ELS) yields cognitive impairments of unknown molecular and physiological origin. We found that fragmented maternal care of mice during a neonatal critical period from postnatal days P2–9 elevated dopamine receptor D2R and suppressed D4R expression, specifically within the anterior cingulate cortex (ACC) in only the male offspring. This was associated with poor performance on a two-choice visual attention task, which was acutely rescued in adulthood by local or systemic pharmacological rebalancing of D2R/D4R activity. Furthermore, ELS male mice demonstrated heightened hypothalamic orexin and persistently disrupted sleep. Given that acute sleep deprivation in normally reared male mice mimicked the ACC dopamine receptor subtype modulation and disrupted attention of ELS mice, sleep loss likely underlies cognitive deficits in ELS mice. Likewise, sleep impairment mediated the attention deficits associated with early adversity in human children, as demonstrated by path analysis on data collected with multiple questionnaires for a large child cohort. A deeper understanding of the sex-specific cognitive consequences of ELS thus has the potential to reveal therapeutic strategies for overcoming them. Editor's summary: Early life adversity (ELA) can have cognitive impacts that persist into adulthood, but the underlying brain mechanisms remain elusive. Here, Makino et al. show that fragmented maternal care led to cognitive dysfunction in adult male, but not female, mice. These findings were associated with disrupted sleep patterns and dysregulated dopamine receptor expression in the anterior cingulate cortex. Acute sleep disruption mimicked ELA-induced changes, and pharmacological rebalancing of DR signaling rescued cognitive dysfunction. Analysis of data from a cohort of young children showed that adversity negatively affected attention, and this relationship was mediated by poor sleep, indicating that the coupling of adversity, sleep, and attention is conserved across species. —Daniela Neuhofer [ABSTRACT FROM AUTHOR]

Background and Objectives Insufficient ethnoracial diversity is a pervasive challenge in Alzheimer's disease (AD) research. The Recruitment Innovations for Diversity Enhancement (RIDE) is grounded in the premise that culturally informed narratives of research participation can inspire individuals from a given culture-sharing group to consider research enrollment. This study examines factors associated with interest in AD research among Black or African American adults following exposure to RIDE narrative campaign materials. Research Design and Methods A community-based sample of 500 Black or African American adults viewed RIDE narrative materials online and completed a survey of perceptions about research, AD risk, and likelihood of enrolling in AD research. Logistic regression examined predictors and mediators of self-reported likelihood of participating in AD research. Results Most (72%) participants reported interest in being contacted for AD research opportunities. After controlling for key variables, prior experience with clinical research and trust in medical researchers emerged as independent predictors of likelihood of enrolling in AD research. Perceived burden of AD research partially mediated the effects of prior research experience and trust on likelihood of enrollment. Perceived benefits of AD research also played a mediating role, accounting for over one third of the effect of trust on likelihood of enrollment. Discussion and Implications This study advances the field's understanding of how narrative may function to enhance diversity in AD research. Findings suggest that participant narratives should address experiences regarding the burdens and potential benefits of AD research participation as these factors may influence decisions leading to subsequent research enrollment. [ABSTRACT FROM AUTHOR]

Sullivan EL, Cameron JL. A rapidly occurring compensatory decrease in physical activity counteracts diet-induced weight loss in female monkeys. Am J Physiol Regul Integr Comp Physiol 298: R1068-RI074, 2010. First published January 13, 2010; doi: 10.1152/ajpregu.00617.2009.--To study changes in energy balance occurring during the initial phases of dieting, 18 adult ovariectomized female monkeys were placed on a low-fat diet, and available calories were reduced by 30% compared with baseline consumption for 1 mo. Surprisingly, there was not significant weight loss; however, daily activity level (measured by accelerometry) decreased soon after diet initiation and reached statistical significance by the 4th wk of dieting (18 [+ or -] 5.6% decrease, P = 0.02). During a 2nd mo of dieting, available calories were reduced by 60% compared with baseline consumption, leading to 6.4 [+ or -] 1.7% weight loss and further suppression of activity. Metabolic rate decreased by 68 [+ or -] 12 kcal/day, with decreased activity accounting for 41 [+ or -] 9 kcal/day, and the metabolic activity of the weight lost accounting for 21 [+ or -] 5 kcal/day. A second group of three monkeys was trained to run on a treadmill for 1 h/day, 5 days/wk, at 80% maximal capacity, leading to increased calorie expenditure of 69.6 [+ or -] 10.7 kcal/day (equivalent to 49 kcal/day for 7 days). We conclude that a diet-induced decrease in physical activity is the primary mechanism the body uses to defend against diet-induced weight loss, and undertaking a level of exercise that is recommended to counteract weight gain and promote weight loss is able to prevent the compensatory decrease in physical activity-associated energy expenditure that slows diet-induced weight loss. obesity; calorie reduction; activity doi: 10.1152/ajpregu.00617.2009.

The role of energy imbalance versus psychosocial stress in the pathogenesis of female reproductive dysfunction characterized by anovulation and amenorrhea remains controversial. In women, functional hypothalamic amenorrhea can develop in the absence of significant weight loss, excessive exercise, or profound psychosocial disruption. We posited, therefore, that commonplace, seemingly minor stressors that alone would have minimal impact upon reproductive function might interact synergistically such that combinations of stressors would cause a greater impairment of the reproductive axis than any single stressor alone. We then developed a monkey model to test this hypothesis. Adult female cynomolgus monkeys with normal menstrual cycles were randomized into three experimental groups and studied over four menstrual cycles. The groups were: low-level psychosocial stress (i.e., moving to a new housing environment; Move, n = 8), moderate energy imbalance (Exercise + Diet, n = 9); and all stressors in combination (Move + Exercise + Diet, n = 10). Food intake, body weight, menstrual cyclicity, and reproductive hormones were assessed for two control menstrual cycles followed by two experimental cycles during which the monkeys experienced the stressors. Abnormal cycles were considered to be abnormally long or anovulatory cycles. Few abnormal cycles occurred in the Move group (1 of 8 monkeys) and in the Exercise + Diet group (1 of 9 monkeys). In contrast, 7 of 10 monkeys in the Move + Exercise + Diet group displayed at least one abnormal cycle ([chi square] = 9.61, P = 0.008). These findings suggest that infertility due to hypotbalamic hypogonadism can result from the combination of commonplace, seemingly minor stressors that often escape clinical attention. exercise; diet; psychosocial stress; reproduction doi:10.1152/ajpendo.00662.2006

Physical activity is an important physiological variable impacting on a number of systems in the body. In rodents and several species of domestic animals, levels of physical activity have been reported to vary across the estrous cycle; however, it is unclear whether such changes in activity occur in women and other primates across the menstrual cycle. To determine whether significant changes in activity occur over the menstrual cycle, we continuously measured physical activity in seven adult female rhesus monkeys by accelerometry over the course of one menstrual cycle. Monkeys were checked daily for menses, and daily blood samples were collected for measurement of reproductive hormones. All monkeys displayed ovulatory menstrual cycles, ranging from 23 to 31 days in length. There was a significant increase in estradiol from the early follicular phase to the day of ovulation ([F.sub.1.005,5.023] = 40.060, P = 0.001). However, there was no significant change in physical activity across the menstrual cycle ([F.sub.2,12] = 0.225, P = 0.802), with activity levels being similar in the early follicular phase, on the day of the preovulatory rise in estradiol and during the midluteal phase. Moreover, the physical activity of these monkeys was not outside the range of physical activity that we measured in 15 ovariectomized monkeys. We conclude that, in primates, physical activity does not change across the menstrual cycle and is not influenced by physiological changes in circulating estradiol. This finding will allow investigators to record physical activity in female primates without the concern of controlling for the phase of the menstrual cycle. estradiol; accelerometer; reproductive hormones doi:10.1152/ajpendo.00497.2006

The increased prevalence of overweight adults has serious health consequences. Epidemiological studies suggest an association between low activity and being overweight; however, few studies have objectively measured activity during a period of weight gain, so it is unknown whether low activity is a cause or consequence of being overweight. To determine whether individual differences in adult weight gain are linked to an individual's activity level, we measured activity, via accelerometry, over a prolonged period (9 mo) in 18 adult female rhesus monkeys. Weight, food intake, metabolic rate, and activity were first monitored over a 3-mo period. During this period, there was mild but significant weight gain (5.5 [+ or -] 0.88%; t = -6.3, df = 17, P < 0.0001), whereas caloric intake and activity remained stable. Metabolic rate increased, as expected, with weight gain. Activity level correlated with weight gain (r = -0.52, P = 0.04), and the most active monkeys gained less weight than the least active monkeys (t = -2.74, df = 8, P = 0.03). Moreover, there was an eightfold difference in activity between the most and least active monkeys, and initial activity of each monkey was highly correlated with their activity after 9 mo (r = 0.85, P < 0.0001). In contrast, food intake did not correlate with weight gain, and there was no difference in weight gain between monkeys with the highest vs. lowest caloric intake, total metabolic rate, or basal metabolic rate. We conclude that physical activity is a particularly important factor contributing to weight change in adulthood and that there are large, but stable, differences in physical activity among individuals. exercise; obesity; weight gain; energy balance doi:10.1152/ajpregu.00069.2006.

Severe undernutrition can delay the maturing reproductive process or the onset of puberty. Lack of food, and to a lesser extent, intensive exercise, prevent the formation of reproductive functions. Fortunately, restored good nutrition can reverse the threat of delayed puberty in children and infertility in adulthood. This reversal explains normal reproduction even among chronically malnourished populations. Anorexia nervosa is the exception to this rule, whereby normal hormonal levels may never be achieved even after appropriate weight gain.