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191.
The dual systems model of adolescent risk‐taking portrays the period as one characterized by a combination of heightened sensation seeking and still‐maturing self‐regulation, but most tests of this model have been conducted in the United States or Western Europe. In the present study, these propositions are tested in an international sample of more than 5000 individuals between ages 10 and 30 years from 11 countries in Africa, Asia, Europe and the Americas, using a multi‐method test battery that includes both self‐report and performance‐based measures of both constructs. Consistent with the dual systems model, sensation seeking increased between preadolescence and late adolescence, peaked at age 19, and declined thereafter, whereas self‐regulation increased steadily from preadolescence into young adulthood, reaching a plateau between ages 23 and 26. Although there were some variations in the magnitude of the observed age trends, the developmental patterns were largely similar across countries.  相似文献   
192.
过去的研究发现,在经历挫折后,相比于不听音乐,听积极音乐能提升人们的希望感。然而,研究者并不清楚积极音乐和消极音乐在提升希望感上是否存在差异,也不清楚这种差异是否由于两种音乐在诱发的积极情绪或消极情绪的差异造成的。文章通过三个实验来考察这些问题。实验一发现,在无挫折的情况下,积极音乐相比消极音乐诱发了更强的希望感。实验二发现,这种效应同样存在于人们回忆挫折之后,并且是积极情绪在其中起中介作用。实验三则通过设置控制组进一步发现,这种效应是由积极音乐对希望感的提升作用和消极音乐对希望感的降低作用共同引起的。文末讨论了该发现的意义。  相似文献   
193.
Duchenne/Becker muscular dystrophy (DBMD) and spinal muscular atrophy (SMA) are rare neuromuscular disorders that present challenges to therapeutic and clinical trial decision making. We developed an interactive, evidence-based online tool designed to encourage thoughtful deliberation of the pros and cons of trial participation and to inform meaningful discussions with healthcare providers. Prior research demonstrates the importance of tool availability at the time each family is considering trial participation, which may be prior to the informed consent process. The tool is intended to be easily modified to other pediatric disease communities. Tool development was informed by prior qualitative research, literature reviews, and stakeholder input. Specific items were derived based on an online exploratory questionnaire of parents whose children participated in a trial for DBMD or SMA to understand motivations for participation. Parent participants in the exploratory survey reported strong impact of altruistic and individual benefit motivations and placed much greater emphasis on anticipated trial benefits than on harms when making participation decisions. We used this data to develop the evidence-based deliberation tool using a community-engaged approach. We initially targeted the tool for DBMD while using SMA survey data to evaluate ease of transition to that population. We conducted two iterative sets of activities to inform development and refinement of the tool: (1) community engagement of key stakeholders and (2) user experience testing. These activities suggest that the tool may increase deliberation and the weighing of benefits and harms. Ongoing evaluation will determine the acceptability and efficacy of this online intervention.  相似文献   
194.
The present study examined persistence and relapse of reinforced behavioral variability in pigeons. Pigeons emitted four‐response sequences across two keys. Sequences produced food according to a lag schedule, in which a response sequence was followed by food if it differed from a certain number of previous sequences. In Experiment 1, food was delivered for sequences that satisfied a lag schedule in both components of a multiple schedule. When reinforcement was removed for one component (i.e., extinction), levels of behavioral variability decreased for only that component. In Experiment 2, food was delivered for sequences satisfying a lag schedule in one component of a multiple schedule. In the other component, food was delivered at the same rate, but without the lag variability requirement (i.e., yoked). Following extinction, levels of behavioral variability returned to baseline for both components after response‐independent food delivery (i.e., reinstatement). In Experiment 3, one group of pigeons responded on a lag variability schedule, and the other group responded on a lag repetition schedule. For both groups, levels of behavioral variability increased when alternative reinforcement was suspended (i.e., resurgence). In each experiment, we observed some evidence for extinction‐induced response variability and for variability as an operant dimension of behavior.  相似文献   
195.
We discuss measuring and detecting influential observations and outliers in the context of exponential family random graph (ERG) models for social networks. We focus on the level of the nodes of the network and consider those nodes whose removal would result in changes to the model as extreme or “central” with respect to the structural features that “matter”. We construe removal in terms of two case-deletion strategies: the tie-variables of an actor are assumed to be unobserved, or the node is removed resulting in the induced subgraph. We define the difference in inferred model resulting from case deletion from the perspective of information theory and difference in estimates, in both the natural and mean-value parameterisation, representing varying degrees of approximation. We arrive at several measures of influence and propose the use of two that do not require refitting of the model and lend themselves to routine application in the ERGM fitting procedure. MCMC p values are obtained for testing how extreme each node is with respect to the network structure. The influence measures are applied to two well-known data sets to illustrate the information they provide. From a network perspective, the proposed statistics offer an indication of which actors are most distinctive in the network structure, in terms of not abiding by the structural norms present across other actors.  相似文献   
196.
This study investigated 5-year-old Mandarin-speaking children’s comprehension of wh-questions, universal statements and free choice inferences. Previous research has found that Mandarin-speaking children assign a universal interpretation to sentences with a wh-word (e.g., shei ‘who’) followed by the adverbial quantifier dou ‘all’ (Zhou in Appl Psycholinguist 36:411–435, 2013). Children also compute free choice inferences in sentences that contain a modal verb in addition to a wh-word and dou (Zhou, in: Nakayama, Su, Huang (eds.) Studies in Chinese and Japanese language acquisition: in honour of Stephen Crain. John Benjamins Publishing Company, Amsterdam, pp 223–235, 2017). The present study used a Question-Statement Task to assess children’s interpretation of sentences containing shei + dou, both with and without the modal verb beiyunxu ‘was allowed to’, as well as the contrast between sentences with shei + dou, which are statements for adults, versus ones with dou + shei, which are wh-questions for adults. The 5-year-old Mandarin-speaking child participants exhibited adult-like linguistic knowledge of the semantics and pragmatics of wh-words, the adverbial quantifier dou, and the deontic modal verb beiyunxu.  相似文献   
197.
The present study used a Truth Value Judgment Task to investigate whether changes in sentence structure lead to corresponding changes in the assignment of scope relations by Mandarin-speaking children and adults. In one condition, participants were presented with ordinary negative sentences containing disjunction; this condition was designed to verify the existing claim that disjunction is a positive polarity item for adult speakers of Mandarin, but not for child speakers. In a second condition, participants were presented with negative sentences where the disjunction phrase was preposed from object position; this condition was designed to examine the extent to which changes in sentence structure can result in changes in scope assignments to negated disjunctions. The results indicate that the preposed disjunction phrase undergoes reconstruction for children, whereas reconstruction is blocked for adults. This finding also suggests that Mandarin-speaking children and adults exhibit different scope preferences for negated disjunctions, regardless of where the disjunction phrase appears in the surface syntax.  相似文献   
198.
The present studies sought to investigate the mapping relations between language and cognition by focusing on how Mandarin-speaking children acquire the mapping between their conceptual knowledge of possession and their linguistic expressions of possession. Two experiments were conducted. Experiment 1 used a comprehension task to explore whether young children are able to map their knowledge of possessive constructions onto their interpretation of possessive relations. Experiment 2 employed a production task to examine whether they are able to map their knowledge of possessive relations onto their linguistic expressions of possession. The findings were that 4-year-olds exhibited correct comprehension and production of possessive DE constructions, indicating that by age 4, Mandarin-speaking children have already established the mapping between their conceptual knowledge of possession and their linguistic expressions of possession. By contrast, 3-year-olds exhibited response patterns that suggest a developmental stage where they use noun–noun compounds to represent possessive relations before they map possessive relations onto possessive constructions.  相似文献   
199.
Many, but not all, young children with high levels of fearful inhibition will develop internalizing problems. Individual studies have examined either child regulatory or environmental factors that might influence the level of risk. We focused on the interaction of regulation and environment by assessing how early fearful inhibition at age 2, along with inhibitory control and maternal negative behaviors at age 3, interactively predicted internalizing problems at age 6. A total of 218 children (105 boys, 113 girls) and their mothers participated in the study. Results indicated a three-way interaction among fearful inhibition, inhibitory control, and maternal negative behaviors. The correlation between fearful inhibition and internalizing was significant only when children had low inhibitory control and experienced high levels of maternal negative behaviors. Either having high inhibitory control or experiencing low maternal negative behaviors buffered against the adverse effect caused by the absence of the other. These findings highlight the importance of considering associations among both within-child factors and environmental factors in studying children’s socioemotional outcomes.  相似文献   
200.
马泽威  全鹏 《心理科学》2015,(2):379-382
考察抑郁在青少年核心自我评价与自杀意念间的中介作用。对502名高中生进行量表测评。通过偏差校正的Bootstrap法和有先验信息的MCMC法求出中介效应值的95%置信区间分别为[-.030,-.011]和[-.024,-.014],提示抑郁的中介效应显著。效应量k2、R2med分别为.124、.104,偏差校正的Bootstrap法抽样5000次后,构建的效应量的95%置信区间分别为[.070,.178]、[.063,.156],两种指标共同验证效应量为中等。研究结果说明抑郁在核心自我评价与自杀意念间起部分中介作用,效应量中等。  相似文献   
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