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151.
多感觉整合是对不同感官信息进行选择、联系、统一乃至解释的加工过程, 它需要神经系统不同功能区域的共同投入与相互协调, 以实现多种感觉信息的时间捆绑以及全局性的预测编码。而γ神经振荡因具有反映神经皮层兴奋/抑制的平衡状况, 实现多感官信息的时间同步, 以及通过跨频耦合实现全局性预测编码的特点, 在多感觉整合的加工过程中发挥着重要作用。相比正常个体, 自闭症患者神经系统中的GABA中间神经元存在结构与功能异常, 导致γ神经振荡紊乱, 由此破坏了正常的时间同步以及预测编码加工, 并最终引发多感觉整合失调。基于上述因果关联, 未来研究可结合无创可逆性干预技术, 以γ节律神经振荡为生物反馈指标, 形成科学系统化的临床干预治疗方案。 相似文献
152.
创造力究竟是怎么产生的, 目前尚未得出一致的结论。神经电生理技术因其高时间分辨率, 可以准确地揭示创造力产生进程中的神经振荡机制, 从而帮助人们更深刻地理解创造力的本质。近年来的研究发现, 单节律alpha神经振荡会随着创造力的增加而增强, 这反映了创造力产生过程中的内部信息加工需求增加、自上而下的抑制控制增强。同时, 多频段神经振荡交叉节律耦合体现了创造性产生过程中额叶、颞叶和顶叶等多脑区之间信息交流的动态变化。未来研究应该以整合理论框架为基础, 结合多层次多方法的研究工具, 引进更生态化的数理计算方法, 并利用计算神经科学建模来预测个体创造力发展趋势, 从而全面深刻地认识创造力的本质。 相似文献
153.
物质丰富的时代, 如何抵御美味食物线索带来的食物渴求, 并限制饮食从而保持健康成为人们关注的重要话题之一。近年来, 国内学者为了探讨节食成功的原因, 创建中国食物图片库, 考察限制性饮食的认知神经机制, 以及成功和失败限制性饮食者的脑机制差异; 开展了特质食物渴求及中国特色的辣食渴求的认知神经研究。对推进饮食行为研究的理论发展, 也为肥胖、饮食失调等健康干预工作提供重要支持。 相似文献
154.
Lee Ellis 《Aggressive behavior》1986,12(1):57-71
Within the framework of modern evolutionary theory, arguments are reviewed that the nonlegal equivalent of aggressive criminal behavior may have evolved by natural selection among mammals, particularly primates, as part of their overall approach to reproduction. If so, the commission of aggressive crimes (or their nonlegal equivalent) by humans, and even efforts to prevent fellow social group members from being victimized by aggressive crimes, may also be partially explainable in natural selection terms. The plausibility of this deduction was explored, first, by specifying the three elements that a human act must have to be regarded as an aggressive crime. Summarily, these were that (1) injury to a victim must be a likely result of the act, (2) the act must be intended, and (3) the act must elicit negative responses from those witnessing it. The primate behavior literature was examined for evidence that some behavior of nonhumans met all three conditions. Affirmative results were obtained. Therefore, while further research is in order, human aggressive criminal behavior, as well as human efforts to control it, seem to have close parallels in other primates. This would be consistent with the notion that aggressive criminal behavior (along with its condemnation by fellow group members) is part of a social system produced and sustained by natural selection. 相似文献
155.
A new multiobjective linear programming (MOLP) algorithm is presented. The algorithm uses a variant of Karmarkar's interior-point algorithm known as the affine-scaling primal algorithm. Using this single-objective algorithm, interior search directions are generated and used to provide an approximation to the gradient of the (implicitly known) utility function. The approximation is guided by assessing locally relevant preference information for the various interior directions through interaction with a decision maker (DM). The resulting algorithm is an interactive approach that makes its progress towards the solution through the interior of the constraints polytope. 相似文献
156.
Jennifer N. Fritz Christopher T. Roath Patricia T. Shoemaker A. Blair Edwards Louisa A. Hussein Natalie K. Villante Channing A. Langlinais Lisa A. Rettig 《Journal of applied behavior analysis》2020,53(3):1688-1701
Studies have shown that the multiple-stimulus without replacement (MSWO) preference assessment is an effective assessment format for identifying preferred items. However, it is possible that factors other than reinforcer quality might influence selections by some individuals when the MSWO array consists of edible items. The validity of the MSWO results was evaluated by comparing items identified as most and least preferred by the MSWO assessment in a concurrent-schedule (CS) format. Varying edible items were used in each study. The MSWO format accurately identified the higher quality edible item for most participants across studies (76%); however, the MSWO format did not predict the highest quality edible item in the CS assessment for 20% to 30% of participants in each study. 相似文献
157.
AbstractOptic flow (OF) has been utilized to investigate the sensory integration of visual stimuli during postural control. It is little known how the OF speed affects the aging brain during the sensory integration process of postural control. This study was to examine the effect of OF speeds on the brain activation using functional near-infrared spectroscopy (fNIRS) and postural sway between younger and older adults. Eleven healthy younger adults (5M/6F, age 22?±?1-year-old) and ten healthy older adults (4M/6F, age 71?±?5-year-old) participated in this study. A virtual reality headset was used to provide the OF stimulus at different speeds. A forceplate was used to record the center-of-pressure to compute the amplitude of postural sway (peak-to-peak). Compared with younger adults, older adults showed significantly increased activation in the OF speed of 10?m/s and decreased activation in the OF speed of 20?m/s in the left dorsolateral prefrontal cortex. Older adults also showed decreased activation in the left temporoparietal region (VEST) in the OF speed of 20?m/s. A significant difference in peak-to-peak was found between groups. Our results indicated that age might be associated with the ability to process fast OF stimulation. 相似文献
158.
The Borg centiMax Scale, is a psychophysically composed general intensity ratio scale, which could enable more precise inter- and intraindividual comparisons of the intensity of depressive symptoms. In the present study, the properties of the centiMax scale were examined in 38 patients with clinical depression and 109 students. Additionally, preliminary centiMax cut-off scores for mild, moderate and severe depression were estimated. The psychometric properties of the centiMax were found to be satisfactory regarding internal consistency, convergent, discriminative and predictive validity. Moreover, the centiMax was demonstrated to provide meaningful comparisons of symptom intensity, which makes it possible to evaluate the relative importance of individual symptoms in a profile and make more precise comparisons within and between individuals. With regard to intraindividual comparisons, patients rated , for example, the intensity of feeling “guilt” twice as strong as feelings of “being punished,” and the intensity of “loss of pleasure” almost three times as strong as “being punished.” With regard to interindividual comparisons, patients rated e.g., the intensity of “being punished” as 12 times stronger than controls, and the intensity of “worthlessness” about nine times stronger. In conclusion, the centiMax was shown to be reliable and valid for assessing depressive symptoms. The centiMax with level anchored ratio data, appears to be highly advantageous as it permits rather precise values of symptom intensity for intra- and interindividual comparisons that could be useful in the diagnostic process and in treatment planning. 相似文献
159.
Katarina Kornaros Sofia Zwedberg Eva Nissen Björn Salomonsson 《Infant mental health journal》2020,41(1):108-125
A child's emotional and social development depends on the parents’ provision of optimal support. Many parents with perinatal distress experience difficulties in mastering parenthood and seek help from professionals within primary healthcare. A clinical project was launched in Stockholm, where psychodynamic psychotherapists provided short-term consultations at Child Health Centers. This study qualitatively explored parents’ experiences of perinatal distress and of receiving help by nurses and therapists in the project. Thirteen parents were interviewed, and their responses were analyzed with a hermeneutical method. Three main themes crystallized; accessibility of psychological help and detection of emotional problems; experiences of therapy at the Child Health Center; and the therapists’ technique. Parents were also clustered into three so-called ideal types: the insecure; parents in crisis; and parents with lifelong psychological problems. Parents experienced obstacles in accessing psychological care within primary healthcare. Psychotherapists with a holistic family perspective and who managed to oscillate between insight-promoting and supportive interventions were especially appreciated. Patient categories who benefitted from insight promotion and support, respectively, were identified. 相似文献
160.
Attention-Deficit/Hyperactivity Disorder (ADHD) is related to suboptimal decision making in experimental tasks and to real-life risk-taking behavior (RTB) such as substance abuse and unsafe traffic conduct. In this preregistered study, we tested whether these associations are mediated by need for cognition—the extent to which one tends towards, and enjoys, analytical thought. In a large sample of young adults (N = 463, Mage = 19.7 years), we tested whether need for cognition mediated the association between self-reported ADHD symptoms on the one hand and decision-making strategy complexity on an experimental gambling task and self-reported real-life RTB on the other hand. Preregistered confirmatory analyses indicated first that ADHD symptoms were positively associated with real-life RTB, but the association was not mediated by need for cognition. Second, ADHD symptoms were not related to decision-making strategy complexity, and need for cognition was not a significant mediator. Explorative analyses revealed that (a) need for cognition was associated with higher decision-making accuracy and slower reaction time; (b) need for cognition was related to inattentive but not to hyperactive/impulsive ADHD symptoms; (c) need for cognition was associated with health-related RTB but not interpersonal RTB; and (4) only the association between inattention and health-related RTB was mediated by need for cognition. We conclude that need for cognition is not a mediator in the association between ADHD symptoms and RTB. Additionally, we conclude that neither ADHD symptoms nor need for cognition predict decision-making strategy complexity. Implications for both future research and clinical practice are discussed. 相似文献