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61.
Previous research on preference between variable-interval terminal links in concurrent chains has most often used variable-duration terminal links ending with a single reinforcer. By contrast, most research on resistance to change in multiple schedules has used constant-duration components that include variable numbers of reinforcers in each presentation. Grace and Nevin (1997) examined both preference and resistance in variable-duration components; here, preference and resistance were examined in constant-duration components. Reinforcer rates were varied across eight conditions, and a generalized-matching-law analysis showed that initial-link preference strongly over-matched terminal-link reinforcer ratios. In multiple schedules, baseline response rates were unaffected by reinforcer rates, but resistance to intercomponent food, to extinction, and to intercomponent food plus extinction was greater in the richer component. The between-component difference in resistance to change exhibited additive effects for the three resistance tests, and was systematically related to reinforcer ratios. However, resistance was less sensitive to reinforcer ratios than was preference. Resistance to intercomponent food and to intercomponent food plus extinction was more sensitive to reinforcer ratios in the present study than in Grace and Nevin (1997). Thus, relative to variable-duration components, constant-duration components increased the sensitivity of both preference and relative resistance, supporting the proposition that these are independent and convergent measures of the effects of a history of reinforcement. 相似文献
62.
Athlete perspectives on the enablers and barriers to nutritional adherence in high-performance sport
ObjectivesPoor adherence to nutritional guidance by athletes may compromise their health and performance. Enhancing adherence is therefore an important performance and welfare strategy. The aim of this study was to qualitatively explore the barriers and enablers of elite athletes' adherence to nutritional guidelines.DesignUnderpinned by our constructionist epistemological position and our relativist ontology, we conducted a qualitative study using focus groups.MethodsWe used the Capability, Opportunity, and Motivation Behaviour (COM-B) model and the Theoretical Domains Framework (TDF) to conduct focus group discussions with a purposive sample of 39 UK-based funded athletes (mean age = 23 ± 3.81), participating in either Olympic and Paralympic sport (n = 30) or professional sport (n = 9), who had access to a nutritionist. Data were analysed using reflexive thematic analysis.ResultsAthlete adherence to nutritional guidance was seasonal and included inadequate energy intakes and episodes of binge eating. Underpinning these behaviours, athletes' emotional barriers (motivation) are reinforced through their social interactions within the high-performance environment (opportunity) and athletes' training environment limits developmental opportunities for food planning (capability). However, a holistic-developmental approach by the sports nutritionists (opportunity) supports athlete wellbeing and nutritional adherence.ConclusionThese findings advance theoretical understanding of the barriers and enablers of nutritional adherence amongst elite-level athletes in high-performance sport and present a number of significant implications for athlete support personnel seeking to enhance performance in demanding sporting contexts. Drawing on the Behaviour Change Wheel (BCW), recommendations include the need to 1) train and educate sports nutritionists in human behaviour, 2) update regulations for sports nutrition profession practice to acknowledge the skills required to support athletes' emotional wellbeing, 3), educate coaches on the sensitivity of body weight and composition and develop guidelines for monitoring athletes' body weight and composition in sport, 4) persuade influential leaders to develop culture guidelines that shift the performance-narrative of high-performance (i.e., environmental restructuring). 相似文献
63.
We followed an ethnically and socioeconomically diverse sample of preadolescent girls with ADHD (n = 140) and matched comparison girls (n = 88) over a period of 5 years, from middle childhood through early/midadolescence, with the aim of determining whether childhood levels of executive function (EF) would predict adolescent multi-informant outcomes of social functioning and psychopathology, including comorbidity between externalizing and internalizing symptomatology. Predictors were well-established measures of planning, response inhibition, and working memory, along with a control measure of fine motor control. Independent of ADHD versus comparison group status, (a) childhood planning and response inhibition predicted adolescent social functioning and (b) childhood planning predicted comorbid internalizing/externalizing disorders in adolescence. Subgroup status (ADHD-Combined, ADHD-Inattentive, and comparison) moderated the relationship between childhood planning and adolescent internalizing/externalizing comorbidity, with the combined type revealing particularly strong associations between baseline planning and adolescent comorbidity. Mediation analyses indicated that adolescent social functioning mediated the prediction from childhood EF to comorbidity at follow-up; in turn, in the girls with ADHD, adolescent comorbidity mediated the prediction from childhood EF to social functioning at follow-up. We conclude that childhood interventions should target EF impairments in addition to behavioral symptoms. 相似文献
64.
Kenneth S. Shultz Deborah A. Olson Eric M. Vogelsang 《Adultspan: Theory Research & Practice》2019,18(2):99-111
An increasing number of older workers are attempting career changes; however, little is known about the antecedents or outcomes of these changes. Results indicate that perceived objective and perceived subjective career‐change success are predicted by different combinations of variables. Implications for both future research and practice are discussed. 相似文献
65.
Adolescent risk-taking behavior has been associated with age-related changes in striatal activation to incentives. Previous cross-sectional studies have shown both increased and decreased striatal activation to incentives for adolescents compared to adults. The monetary incentive delay (MID) task, designed to assess functional brain activation in anticipation of reward, has been used extensively to examine striatal activation in both adult and adolescent populations. The current study used this task with a longitudinal approach across mid-adolescence and late adolescence/early adulthood. Twenty-two participants (13 male) were studied using the MID task at two time-points, once in mid-adolescence (mean age = 16.11; SD = 1.44) and a second time in late adolescence/early adulthood (mean age = 20.14; SD = .67). Results revealed greater striatal activation with increased age in high- compared to low-incentive contexts (incentive magnitude), for gain as well as for loss trials (incentive valence). Results extend cross-sectional findings and show reduced striatal engagement in adolescence compared to adulthood during preparation for action in an incentive context. 相似文献
66.
建构水平理论(Construal level theory)认为时间能够独立地改变评价对象的建构水平,从而对对象的不同特征赋予不同的权重。个体倾向于用抽象的整体的特征表征时距远的事物,而用具体的局部的特征表征时距近的事物。空间距离不同的评价对象是否也遵循同样的规律?在考察时空距离与个人相关性的基础上,通过2(时间距离:明天和十年后)×2(空间距离:近地点和远地点)×2(特征类型:样例特征和类型特征)三因素被试间实验设计,探讨时间距离、空间距离、特征类型对态度的影响。结果发现,空间距离影响人们对事物的态度。在远空间距离水平上,时间距离对态度的影响显著,而在近空间距离水平上时间距离对态度的影响不显著;在远空间条件下,时距远的对象优先注意类型化的特征,时距近的对象优先注意样例化特征。最后,在建构水平理论框架内讨论了实验结果。 相似文献
67.
Stella Vosniadou Dimitrios Pnevmatikos Nikos Makris Despina Lepenioti Kalliopi Eikospentaki Anna Chountala Giorgos Kyrianakis 《Cognitive Science》2018,42(6):1860-1886
Prior research has investigated the recruitment of inhibition in the use of science/mathematics concepts in tasks that require the rejection of a conflicting, nonscientific initial concept. The present research examines if inhibition is the only EF skill recruited in such tasks and investigates whether shifting is also involved. It also investigates whether inhibition and/or shifting are recruited in tasks in which the use of science/mathematics concepts does not require the rejection of an initial concept, or which require only the use of initial concepts. One hundred and thirty‐three third‐ and fifth‐grade children participated in two inhibition and shifting tasks and two science and mathematics conceptual understanding and conceptual change (CU&C) tasks. All the tasks were on‐line, and performance was measured in accuracy and RTs. The CU&C tasks involved the use of initial concepts and of science/mathematics concepts which required conceptual changes for their initial formation. Only in one of the tasks the use of the science/mathematics concepts required the concurrent rejection of an initial concept. The results confirmed that in this task inhibition was recruited and also showed that the speed of shifting was a significant predictor of performance. Shifting was a significant predictor of performance in all the tasks, regardless of whether they involved science/mathematics or initial concepts. It is argued that shifting is likely to be recruited in complex tasks that require multiple comparisons of stimuli and the entertainment of different perspectives. Inhibition seems to be a more selective cognitive skill likely to be recruited when the use of science/mathematics concepts requires the rejection of a conflicting initial concept. 相似文献
68.
69.
Nicolas Favez Francesco Lopes Mathieu Bernard France Frascarolo Chloe Lavanchy Scaiola Antoinette Corboz‐Warnery Elisabeth Fivaz‐Depeursinge 《Family process》2012,51(4):542-556
This article presents a longitudinal study of the development of “family alliance” from pregnancy to toddlerhood in a community sample, as well as its links with the emotional and cognitive development of the child at age 5 years. Family alliance is defined as the quality of the interactive coordination between family members. We consider that the alliance constitutes a context for the child to learn emotion regulation and to develop an understanding of inner states. Family interactions (N = 38) were observed at the 5th month of pregnancy and at 3, 9, and 18 months after birth in a standardized situation of observation (Lausanne Trilogue Play). Marital satisfaction and child temperament were assessed through self‐reported questionnaires. Several outcomes of the child at age 5 years were measured: theory of mind performances, predominant emotional themes in pretend play, internalized and externalized symptoms. Results show that (a) three patterns of evolution of family alliance occur: “high stable” (n = 19), “high to low” (n = 10), and “low stable” (n = 9); (b) a high stable alliance is predictive of better outcomes in children at age 5 years, especially regarding theory of mind; (c) the temperament of the child is predictive of child outcomes; and (d) an interaction effect occurs between family alliance and temperament. These results highlight the importance of both family‐level and individual‐level variables for understanding individual differences in the social and cognitive development of children. 相似文献
70.
In China, rapid economic growth and increasing social problems constitute two basic characteristics of contemporary social change. During the process of dramatic social change, an emerging question is how adolescents' mental health has changed across birth cohorts. The present paper reviews four studies of crosstemporal meta-analysis conducted by us. By meta-analysis of previous literature, we examined changes in mean scores on mental health measures over time (from the early 1990s to the mid-2000s). It was found that since the early 1990s, Chinese adolescents' mental health deteriorated across birth cohorts, shown in increased scores on the negative indicators of mental health (e.g. mental problems, anxiety, and depression), whereas self-esteem as a positive trait decreased. The dropping trend in Chinese adolescents' mental health could be attributed to social change, especially increasing social problems. Therefore, adequate attention must be paid to potential influences of social change on individuals' psychological development. 相似文献