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241.
Verb learning is difficult for children (Gentner, 1982 ), partially because children have a bias to associate a novel verb not only with the action it represents, but also with the object on which it is learned (Kersten & Smith, 2002 ). Here we investigate how well 4‐ and 5‐year‐old children (N = 48) generalize novel verbs for actions on objects after doing or seeing the action (e.g., twisting a knob on an object) or after doing or seeing a gesture for the action (e.g., twisting in the air near an object). We find not only that children generalize more effectively through gesture experience, but also that this ability to generalize persists after a 24‐hour delay.  相似文献   
242.
To harness the complexity of their high‐dimensional bodies during sensorimotor development, infants are guided by patterns of freezing and freeing of degrees of freedom. For instance, when learning to reach, infants free the degrees of freedom in their arm proximodistally, that is, from joints that are closer to the body to those that are more distant. Here, we formulate and study computationally the hypothesis that such patterns can emerge spontaneously as the result of a family of stochastic optimization processes, without an innate encoding of a maturational schedule. In particular, we present simulated experiments with an arm where a computational learner progressively acquires reaching skills through adaptive exploration, and we show that a proximodistal organization appears spontaneously, which we denote PDFF (Proximo Distal Freezing and Freeing of degrees of freedom). We also compare this emergent organization between different arm morphologies—from human‐like to quite unnatural ones—to study the effect of different kinematic structures on the emergence of PDFF.  相似文献   
243.
Previous studies have shown that adults who stutter produce smaller corrective motor responses to compensate for unexpected auditory perturbations in comparison to adults who do not stutter, suggesting that stuttering may be associated with deficits in integration of auditory feedback for online speech monitoring. In this study, we examined whether stuttering is also associated with deficiencies in integrating and using discrepancies between expected and received auditory feedback to adaptively update motor programs for accurate speech production. Using a sensorimotor adaptation paradigm, we measured adaptive speech responses to auditory formant frequency perturbations in adults and children who stutter and their matched nonstuttering controls. We found that the magnitude of the speech adaptive response for children who stutter did not differ from that of fluent children. However, the adaptation magnitude of adults who stutter in response to auditory perturbation was significantly smaller than the adaptation magnitude of adults who do not stutter. Together these results indicate that stuttering is associated with deficits in integrating discrepancies between predicted and received auditory feedback to calibrate the speech production system in adults but not children. This auditory‐motor integration deficit thus appears to be a compensatory effect that develops over years of stuttering.  相似文献   
244.
Developmental psychology plays a central role in shaping evidence‐based best practices for prelingually deaf children. The Auditory Scaffolding Hypothesis (Conway et al., 2009) asserts that a lack of auditory stimulation in deaf children leads to impoverished implicit sequence learning abilities, measured via an artificial grammar learning (AGL) task. However, prior research is confounded by a lack of both auditory and language input. The current study examines implicit learning in deaf children who were (Deaf native signers) or were not (oral cochlear implant users) exposed to language from birth, and in hearing children, using both AGL and Serial Reaction Time (SRT) tasks. Neither deaf nor hearing children across the three groups show evidence of implicit learning on the AGL task, but all three groups show robust implicit learning on the SRT task. These findings argue against the Auditory Scaffolding Hypothesis, and suggest that implicit sequence learning may be resilient to both auditory and language deprivation, within the tested limits. A video abstract of this article can be viewed at: https://youtu.be/EeqfQqlVHLI [Correction added on 07 August 2017, after first online publication: The video abstract link was added.]  相似文献   
245.
Healthy parenting may be protective against the development of emotional psychopathology, particularly for children reared in stressful environments. Little is known, however, about the brain and behavioral mechanisms underlying this association, particularly during childhood and adolescence, when emotional disorders frequently emerge. Here, we demonstrate that psychological control, a parenting strategy known to limit socioemotional development in children, is associated with altered brain and behavioral responses to emotional conflict in 27 at‐risk (urban, lower income) youth, ages 9–16. In particular, youth reporting higher parental psychological control demonstrated lower activity in the left anterior insula, a brain area involved in emotion conflict processing, and submitted faster but less accurate behavioral responses—possibly reflecting an avoidant pattern. Effects were not replicated for parental care, and did not generalize to an analogous nonemotional conflict task. We also find evidence that behavioral responses to emotional conflict bridge the previously reported link between parental overcontrol and anxiety in children. Effects of psychological control may reflect a parenting style that limits opportunities to practice self‐regulation when faced with emotionally charged situations. Results support the notion that parenting strategies that facilitate appropriate amounts of socioemotional competence and autonomy in children may be protective against social and emotional difficulties.  相似文献   
246.
Little consideration has been given to the possibility of human infant development being shaped via lactocrine programming, and by breast milk cortisol levels specifically. Despite animal models indicating that glucocorticoid (GC) exposure via lactation might modify brain development and behavior, only one study has reported that milk cortisol levels were positively associated with infant negative affectivity, especially fearfulness and sadness—early emerging risk factors for internalizing difficulties such as anxiety. The aim of the current study was to investigate whether human milk cortisol is associated with mother‐reported fearfulness and experimentally induced infant fear reactivity. Mother‐infant dyads (n = 65) enrolled in the FinnBrain Cohort Study participated. Breast milk samples were obtained 2.5 months postpartum, and milk cortisol concentrations were ascertained using validated luminescence immunoassay methodology. Infant fear reactivity was assessed using maternal reports 6 months postpartum and in a laboratory 8 months postpartum. There was a significant interaction between infant sex and milk cortisol such that higher milk cortisol was related to higher infant fear reactivity in a laboratory setting in girls (β = 0.36, p = .04) but not in boys (β = ?0.15, p = .40). Milk cortisol was not associated with mother‐reported infant fearfulness. Results suggest that higher human milk cortisol concentrations are associated with elevated experimentally induced fear in infancy. Findings support lactocrine programming, and suggest that mothers may “communicate” vital information about stressful environments via cortisol contained in breast milk, shaping girls' early emotional reactivity.  相似文献   
247.
The aim of this study was to determine the effects of psychological interventions (e.g. cognitive restructuring, relaxation) on physiological and psychological health in osteoarthritis patients. A systematic literature search was done using PubMed, Embase, PsycINFO, Web of Science, China National Knowledge Infrastructure, and Wanfang Database through November 2016. Studies were included if they used a randomized controlled trial designed to explore the effects of psychological interventions in osteoarthritis patients. Two independent authors assessed the methodological quality of the trials using criteria outlined by Jadad et al. Meta-analysis was done with the Revman5.0. Twelve randomized controlled trials, including 1307 osteoarthritis patients, met the study inclusion criteria. Meta-analysis showed that psychological interventions could reduce the levels of pain [standard mean difference (SMD) ?0.28, 95% CI ?0.48, ?0.08, P-value 0.005)] and fatigue (SMD ?0.18, 95% CI ?0.34, ?0.01, P-value 0.04). In addition, psychological interventions significantly improved osteoarthritis patients’ self-efficacy (SMD 0.58, 95% CI 0.40, 0.75, P-value 0.00) and pain coping (MD 1.64, 95% CI 0.03, 3.25, P-value 0.05). Although the effects on physical function, anxiety, depression, psychological disability were in the expected direction, they were not statistically significant. In conclusion, the role of psychological interventions in the management of osteoarthritis remains equivocal. Some encouraging results were seen with regard to pain, pain coping, self-efficacy, and fatigue. We believe that more methodologically rigorous large-scale randomized controlled trials are necessary to answer this study question.  相似文献   
248.
249.
To understand how individuals’ senses of competence are cultivated, scholars have primarily focused on situational factors such as job autonomy and supervisor support. Against this backdrop, we propose that individuals can work as active agents and enhance their sense of competence by initiating actions that aim to master the environment. We adopt the behavioral concordance model and propose that people higher in proactive personality are more likely to engage in proactive behavior that elevates their senses of competence over time. We further propose that such behavioral concordance contributes to boosting a sense of competence is more prominent among those with higher proactive personality. Our predictions are supported by data from 172 employees and their direct supervisors in China, after controlling for the effect of job autonomy and supervisor support for autonomy. Specifically, only those higher in proactive personality engaged in more proactive behavior and increased their sense of competence over time. This study highlights both a self-initiated and a behavioral perspective on understanding the development of a sense of competence.  相似文献   
250.
The great improvement in economic wealth and social welfare over the decade doesn’t promote the Chinese people’s happiness. We construct a theoretical framework which covers economic wealth, social welfare, individual functional capability to explore the impact factors and determinants of the Chinese people’s happiness. Based on a national wide questionnaire survey in China, we test and modify the framework by the method of structural equation model. The empirical findings indicate that there are direct and indirect effects on the formation of happiness. For the direct effect, both the increasing of economic wealth and social welfare improves the national happiness, while the individual functional capability reduces it. For the indirect effect, the individual functional capability also reduces happiness by negatively affecting economic wealth and social welfare. The negative effect that played by individual functional capability overwhelms the positive effect played by economic wealth and social welfare. This causes the Chinese people’s happiness goes down while the economic wealth and social welfare are improving. Finally, we conclude that the Chinese people’s happiness is more about individual functional capability rather than social welfare or economic wealth.  相似文献   
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