Individual Differences in Spatial Memory and Striatal ChAT Activity among Young and Aged Rats

Individual differences in spatial memory among young and aged rats were assessed using memory tasks related to integrity of the hippocampus and the neostriatum. Relationships were then examined between measures of spatial memory and regional choline acetyltransferase (ChAT) activity, a marker for cholinergic integrity. Twenty-four-month-old Long-Evans rats were impaired in comparisons with 6-month-old rats on measures of place learning, working memory, reference memory, and perseveration in water-maze tasks. Aged rats that were impaired on one measure of memory, however, were not necessarily impaired on other measures. ChAT activity in the ventromedial and dorsolateral neostriatum of aged rats was significantly reduced in comparisons with young rats whereas no difference was found in the hippocampus. Aged rats with the most ChAT activity in the anterior ventromedial neostriatum performed best on the place-learning and reference memory tasks but also made the most perseverative errors on the working memory task. In addition, young and aged rats with the most ChAT activity in the anterior dorsolateral neostriatum were those with the least accurate working memory. No relationships were found between ChAT activity in the hippocampus and spatial memory. Thus age-related memory impairment has components that can be segregated by measuring relationships between cholinergic integrity in subregions of the anterior neostriatum and memory tasks with different strategic requirements.     

Using self-determination theory to promote adolescent girls' physical activity: Exploring the theoretical fidelity of the Bristol Girls Dance Project

ObjectivesTo report the theory-based process evaluation of the Bristol Girls' Dance Project, a cluster-randomised controlled trial to increase adolescent girls' physical activity.DesignA mixed-method process evaluation of the intervention's self-determination theory components comprising lesson observations, post-intervention interviews and focus groups.MethodFour intervention dance lessons per dance instructor were observed, audio recorded and rated to estimate the use of need-supportive teaching strategies. Intervention participants (n = 281) reported their dance instructors' provision of autonomy-support. Semi-structured interviews with the dance instructors (n = 10) explored fidelity to the theory and focus groups were conducted with participants (n = 59) in each school to explore their receipt of the intervention and views on the dance instructors' motivating style.ResultsAlthough instructors accepted the theory-based approach, intervention fidelity was variable. Relatedness support was the most commonly observed need-supportive teaching behaviour, provision of structure was moderate and autonomy-support was comparatively low. The qualitative findings identified how instructors supported competence and developed trusting relationships with participants. Fidelity was challenged where autonomy provision was limited to option choices rather than input into the pace or direction of lessons and where controlling teaching styles were adopted, often to manage disruptive behaviour.ConclusionThe successes and challenges to achieving theoretical fidelity in the Bristol Girls' Dance Project may help explain the intervention effects and can more broadly inform the design of theory-based complex interventions aimed at increasing young people's physical activity in after-school settings.     

Statistical Learning Is Not Affected by a Prior Bout of Physical Exercise

This study examined the effect of a prior bout of exercise on implicit cognition. Specifically, we examined whether a prior bout of moderate intensity exercise affected performance on a statistical learning task in healthy adults. A total of 42 participants were allocated to one of three conditions—a control group, a group that exercised for 15 min prior to the statistical learning task, and a group that exercised for 30 min prior to the statistical learning task. The participants in the exercise groups cycled at 60% of their respective O₂max. Each group demonstrated significant statistical learning, with similar levels of learning among the three groups. Contrary to previous research that has shown that a prior bout of exercise can affect performance on explicit cognitive tasks, the results of the current study suggest that the physiological stress induced by moderate‐intensity exercise does not affect implicit cognition as measured by statistical learning.     

A pilot study of women’s affective responses to common and uncommon forms of aerobic exercise

Objective: To test the extent to which participants exposed to an uncommon versus common exercise stimulus would result in more favourable affect at post-task.

Design: Experimental design. Participants (N = 120), American women aged 18–45 years, were randomly assigned to complete 30-min of either the uncommon (HOOP; n = 58) or common (WALK; n = 62) exercise stimulus.

Main outcome measures: Self-reported affect and intentions for future exercise were measured before and after the 30-min exercise bout.

Results: Analyses of covariance were run to compare post-task affect across the HOOP and WALK conditions. At post-task, participants assigned to HOOP reported more positively valenced affect, higher ratings of positive activated affect, lower ratings of negative deactivated affect, and stronger intentions for future aerobic exercise compared to participants assigned to WALK.

Conclusions: Participants who completed an uncommon bout of aerobic exercise (HOOP) reported more favourable affect post-exercise, as well as stronger intentions for future exercise, compared to participants who completed a common bout of aerobic exercise (WALK). Future work using a longitudinal design is needed to understand the relationships between familiarity with an exercise stimulus, affective responses to exercise, motivation for future exercise behaviour and exercise maintenance over time.     

Self-efficacy,planning, and preparatory behaviours as joint predictors of physical activity: A conditional process analysis

Objective: Planning can bridge the gap between intentions and action, but what bridges the gap between planning and action? This study helps to answer the question by disentangling the interrelationships between self-efficacy, planning and preparatory behaviours in predicting physical activity. Preparatory behaviours are tested as a working mechanism of planning. Moreover, it is tested whether the utility of preparatory behaviours depends on an individual’s level of self-efficacy.

Methods: A survey assessed planning, self-efficacy and preparatory behaviours for physical activity. Adults (N = 166) provided data at two measurement points. In a longitudinal model, preparatory behaviours were specified as a mediator between planning and physical activity. Self-efficacy was specified as a possible moderator at two points in the model.

Results: Preparatory behaviours mediated the relationship between planning and physical activity. An interaction between self-efficacy and preparatory behaviours on physical activity was found, indicating that individuals with low self-efficacy beliefs were more active if they engaged more frequently in preparatory behaviours.

Conclusion: Planning seems to stimulate preparatory behaviours, which in turn make future physical activity more likely. Furthermore, as performing preparatory behaviours represent a step forward towards the enactment of behavioural goals, preparatory behaviours may be particular beneficial for individuals afflicted by self-doubts regarding physical activity.     

Health and Aging: A Perspective from the Far East

Singapore is an urban, highly industrialized country in South East Asia. By 2030, one-fifth of the population is projected to be composed of citizens aged above 65 years. Research on aging has largely focused on the effects of deteriorating physical ability on daily functioning capabilities (Iwarsson & Isacsson, 1997; Warr, 1995). More recently, the role of self-perceived usefulness, competence and control on well-being in the elderly have been investigated (Heberlein, Licht & Licht, 1999; Ranzjin, Keeves, Luszcz, & Feather, 1998). In other fields, activity and involvement have been identified as effective coping devices (Nair, 1989; Shalit, 1988). The present study compared the conceptual understanding of the esteem and well-being of the elderly on the dimensions of activity, involvement, and control, as viewed by an undergraduate sample (n = 60) and a cross-section of seniors (n = 71). Three separate factor analyses reflected interesting variations in the conceptual frameworks.     

论医疗行为中的“可容性危险”原则

对合法的医疗行为进行认定,分析医疗的局限性和社会认知差异,认为在医疗活动中,为谋求对疾病认识,应允许医疗活动带有危险性。对可容性危险原则进行法理分析,结合实际案例,分析医疗行为中的“可容性危险”原则的运用以及司法界对该原则的认知。     

Time for change: using implementation intentions to promote physical activity in a randomised pilot trial

Objective: A common barrier to exercise is a perceived lack of time. The current pilot study examined the effects of an implementation intention intervention to enhance exercise self-efficacy, increase confidence to exercise when facing time constraints, and increase physical activity in middle-aged adults (n?=?63, aged 35–69). Design: Participants received a pedometer (Fitbit) to objectively measure activity and were randomly assigned to either a control or intervention condition. After a 1-week baseline, the intervention condition received instructions to plan how, where, and when they would add steps to their daily routine to meet their step goal, using personalised schedules and maps. Both groups were contacted nightly via email. Main Outcome Measures: Physical activity (steps and time spent in moderate-to-vigorous activity), goal achievement, exercise self-efficacy, time-relevant exercise self-efficacy and affect. Results: Compared to the control, the intervention condition significantly increased in steps, time spent in moderate-to-vigorous activity, and time-relevant exercise self-efficacy. Goal achievement was related to greater time-relevant exercise self-efficacy and more positive affect at the daily level. Conclusion: Findings suggest that the personalised planning intervention increased physical activity and confidence in achieving physical activity goals under time constraints. Avenues for future directions, especially for producing more sustained effects, are discussed.     

Social support and verbal interaction are differentially associated with cognitive function in midlife and older age

Social engagement is associated with healthy aging and preserved cognition. Two dimensions of engagement, verbal interactions and perceived support, likely impact cognition via distinct mechanistic pathways. We explored the cognitive benefit of each construct among enrollees (N = 1,052, mean age = 60.2 years) in the Wisconsin Registry for Alzheimer’s Prevention study, who provide neuropsychological and sociobehavioral data at two-year intervals. Outcomes included six cognitive factor scores representing key domains of executive function and memory. Key predictors included self-reported perceived social support and weekly verbal interaction. Results indicated that after adjusting for lifestyle covariates, social support was positively associated with Speed and Flexibility and that verbal interactions were associated with Verbal Learning and Memory. These findings suggest that support, which may buffer stress, and verbal interaction, an accessible, aging-friendly form of environmental enrichment, are uniquely beneficial. Both are integral in the design of clinical and community interventions and programs that promote successful aging.     

自我信息的反应抑制优势：来自神经振荡的证据

为探明个体对自我信息的反应抑制神经机制,记录了被试在完成面孔识别的停止信号任务时的脑电信号。神经振荡结果显示,反应任务中,加工自我面孔引发了更大的同步化δ节律和去同步化β节律;停止任务中,自我面孔引发了更大的去同步化β节律,特别在大脑前额区和中线上。表明,自我信息的反应抑制优势发生在抑制控制阶段,在于增强的β节律的去同步化促进了运动准备,提高了后续的动作抑制的速度。