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261.
ObjectivesThis study examined whether individuals who assigned equal priority to physical activity and an alternative activity exhibited lower levels of participation in physical activities than individuals who assigned higher priority to physical activity than an alternative activity. In addition, we examined whether a measure of prioritisation derived from an algebraic difference index provided a rigorous test of prioritisation effects.DesignWe employed a two-wave prospective design that aimed to predict physical activity participation.MethodPrioritisation, intentions and perceptions of control were measured at the first wave of data collection. After five weeks, we administered follow-up measures of behavioural conflict and physical activity participation.ResultsA hierarchical regression analysis showed that although the algebraic difference index was positively associated with measures of physical activity participation, equal prioritisation did not yield lower levels of physical activity participation than high prioritisation.ConclusionsFindings suggest that equal prioritisation is not a less optimal self-regulatory strategy than high prioritisation in the domain of physical activity. Regression coefficients associated with algebraic difference indexes should be interpreted with caution and consider analyses that examine effects of component measures of prioritisation on physical activity participation.  相似文献   
262.
This article ventures a framework for assessing the contributions capitalism might make to the common good. Capitalism has manifest strengths—efficiency, growth, support for human freedoms, encouragement for collaboration among nations that are not natural allies. Processes that generate these goods have negative consequences as well—the exploitation of labor, environmental harm, the marginalization of the "least advantaged," the reduction of politics to strategies for advancing special interests. To constrain the negative consequences, public oversight is necessary. The challenge is to devise policies that will limit the harms while protecting conditions that enable free markets to flourish. The paper concludes with an illustrative sketch of policy proposals that exemplify this goal.  相似文献   
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264.
IntroductionThere is mixed evidence regarding moderators of the relationship between implicitly and explicitly measured constructs. This study examined this issue with evaluations of exercise relative to health or appearance in a sample of Iranian adolescents. Investigaing automatic associations and reflective constructs might provide important implications for developing interventions targeting exercise behavior in a population with different cultural, social, and economic barriers to exercise than European or North American adolescents.MethodsParticipants were 471 students enrolled in grades 9 to 12, of whom 269 (54.9%) were female. Behavioral regulations, explicit attitudes, and social desirability were investigated as possible moderators. All students completed questionnaire measures of physical activity behavior, attitudes, social desieality and behavioral regulation. They also completed two Go/No Go Association tasks to measure automatic associations of exercise with health and apperarance.ResultsAttitude was a significant moderator of discrepancies between automatic associations of exercise with health and health motives. Interjected regulation moderated implicit-explicit appearance discrepancies. Participants with low social desirability and negative automatic appearance associations had the highest appearance motivation.ConclusionsParticipants focused on the potential of achieving positive health outcomes of exercise rather than physical appearance outcomes, which differs from research from other countries. It is possible that, health was strongly linked with exercise by the pervasive societal pressures in Iran to have a healthy body.  相似文献   
265.
Abstract

Variability in the temporal structure of gait patterns, measured by “Fractal Index” (FI), is thought to represent abundancy of movement patterns facilitating adaptive control of walking. However we do not know how FI changes according to different walking rhythms or if this is repeatable, as needed to exploit the paradigm for rehabilitation. Fourteen healthy young adults synchronised heel contact to an auditory metronome twice each in four conditions (uncued, white noise, pink noise, and red noise) and three sessions. FI differed based on the walking condition while no effect of session was revealed. The results of this study suggest gait fractality changes systematically with different stimuli and can be consistently prescribed in a desired direction within a group of healthy young individuals.  相似文献   
266.
Distortions in sensory experiences that precede a migraine attack have been extensively documented, the most well-known being the visual aura. Distortions in the experience of other senses are also reported as part of an aura, albeit less frequently, together with changes in the perception or ownership of the body or body parts. There are many examples of differences in aspects of visual perception between migraine and control groups, between attacks, but not as much on unusual experiences involving other senses, the sense of the body or the experience of the environment. Seventy-seven migraine (33 with aura) and 74 control participants took part. Anomalous perceptions were experienced by both migraine and control groups, but more with migraine experienced them and rated them as more distressing, intrusive and frequent. Associations with reports of visual triggers of migraine and visual discomfort are presented. This study is the first to show relationships between these factors.  相似文献   
267.
Abstract

In this work, we describe a method for estimating the muscle activity without drawing any assumptions regarding optimality principles in human motor control strategies; further, the method does not require any neural circuitry modeling which limits the neurophysiological terms and estimability of the method. We introduce the concept of system observability, which can reconstruct states from outputs and their derivatives based on system dynamics. Based on neuromuscular system observability, we estimate the muscle activity from joint torques and kinematics of multiple locomotive gaits, while considering the unknown neural inputs as system disturbances. Moreover, to quantify the robustness of the method, the degree of observability and parameter sensitivity are evaluated. Finally, the neurophysiological implications and generality of the method are addressed.  相似文献   
268.
The reliable change index (RCI) is a commonly used method for interpreting change in neuropsychological test scores over time. However, the RCI is a psychometric method that, to date, has not been validated against neuroanatomical changes. Longitudinal neuroimaging and neuropsychological data from baseline and one-year follow-up visits were retrieved from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) database. The RCI was used to identify participants showing reliable decline on memory (ADNI-Mem; = 450) and executive functioning (ADNI-EF; = 456) factor scores. For each factor score, two groups (reliable change vs. no reliable change) were matched on potential baseline confounding variables. Longitudinal neuroanatomical data were analysed using tensor-based morphometry. Analysis revealed that reliable change on ADNI-Mem was associated with atrophy in the medial temporal cortex, limbic cortex, temporal lobe and some regions of the parietal lobe. Similar atrophy patterns were found for reliable change on ADNI-EF, except that atrophy extended to the frontal lobe and the atrophy was more extensive and of higher magnitude. The current study not only validates clinical usage of the RCI with neuroanatomical evidence of associated underlying brain change but also suggests patterns of likely brain atrophy when reliable cognitive decline is detected.  相似文献   
269.
Childhood obesity is a serious health concern that is not yet fully understood. Previous research has linked obesity with neurobehavioral factors such as behavior, cognition, and brain morphology. The causal directions of these relationships remain mostly untested. We filled this gap by using the Adolescent Brain Cognitive Development study cohort comprising 11,875 children aged 9–10. First, correlations between the age- and sex-specific 95th BMI percentile (%BMIp95) and neurobehavioral measures were cross-sectionally analyzed. Effects were then aggregated by neurobehavioral domain for causal analyses. Behavioral genetic Direction of Causation modeling was used to test the direction of each relationship. Findings were validated by longitudinal cross-lagged panel modeling. %BMIp95 correlated with impulsivity, motivation, psychopathology, eating behavior, and cognitive tests (executive functioning, language, memory, perception, working memory). Greater %BMIp95 was also associated with reduced cortical thickness in frontal and temporal brain areas but with increased thickness in parietal and occipital areas. Similar although weaker patterns emerged for cortical surface area and volume. Behavioral genetic modeling suggested causal effects of %BMIp95 on eating behavior (β = 0.26), cognition (β = 0.05), cortical thickness (β = 0.15), and cortical surface area (β = 0.07). Personality/psychopathology (β = 0.09) and eating behavior (β = 0.16) appeared to influence %BMIp95. Longitudinal evidence broadly supported these findings. Results regarding cortical volume were inconsistent. Results supported causal effects of obesity on brain functioning and morphology. The present study highlights the importance of physical health for brain development and may inform interventions aimed at preventing or reducing pediatric obesity.

Research Highlights

  • A continuous measure related to obesity, %BMIp95, has correlations with various measures of brain functioning and structure
  • Behavioral genetic and longitudinal modeling suggest causal links from personality, psychopathology, and eating behavior to %BMIp95
  • Results also indicate directional links from %BMIp95 to eating behavior, cognition, cortical thickness, and cortical surface area
  • Obesity may play a role for healthy brain development during childhood
  相似文献   
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