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121.
近年来大量研究发现音乐训练对认知能力的具有积极影响,一些理论认为音乐训练的广泛迁移效应是通过执行功能起中介作用,但音乐训练与执行功能的关系至今仍存争议。研究将执行功能分为抑制控制、工作记忆和认知灵活性三个子成分,并将抑制控制进一步细分为注意抑制和反应抑制,同时区分工作记忆中主动性控制和反应性控制两种认知过程。通过对比音乐组和控制组在执行功能各任务(Go/No-go, Stroop, AX-CPT, Task-switching)上的行为表现来系统考察音乐训练与执行功能的关系。结果表明音乐训练对执行功能不同子成分的影响具有差异性,其促进效应主要体现在抑制控制中的注意抑制和工作记忆中的主动性控制,对抑制控制中的反应抑制、工作记忆中的反应性控制和认知灵活性影响较小。  相似文献   
122.
本研究以281名老年人为研究对象,探讨了城市变迁中的老年人居住地情感认同、领悟社会支持和控制感的关系。研究使用居住地情感认同问卷、领悟社会支持问卷和控制感问卷为研究工具,采用每次间隔6个月,共3次的纵向追踪设计。结果发现:老年人的居住地情感认同可以正向预测领悟社会支持,老年人的领悟社会支持可以正向预测控制感,老年人的领悟社会支持在居住地情感认同和控制感之间起纵向中介作用。本研究结果揭示了城市老年居民的居住地情感认同对控制感的影响机制,也对提升城市老年居民的控制感具有一定的实践意义。  相似文献   
123.
为考察网络社交媒体使用对青少年生活满意度的影响及其内在心理机制—自我同一性状态的中介作用,采用问卷法对2634名青少年进行调查。结果表明:(1)网络社交媒体使用无法直接预测青少年生活满意度,但可以通过自我同一性状态这一中介变量产生间接影响;(2)网络社交媒体使用对青少年心理发展呈现双重作用,既能通过加强成就型自我同一性状态提高生活满意度,也可以通过增强弥散型自我同一性状态进而削弱青少年生活满意度。  相似文献   
124.
父母冲突与青少年的身心健康息息相关。本研究以366名青少年为被试,采用问卷调查法研究父母冲突频率与青少年生活满意度间的关系,以及父母冲突时青少年行为反应在其中的中介作用。结果表明:(1)父母冲突频率显著负向预测青少年生活满意度;(2)青少年的介入行为与生活满意度呈显著正相关,回避行为则与生活满意度呈显著负相关;(3)在主张–回避的父母冲突场景中,青少年的回避行为在父母冲突频率与生活满意度间起到部分中介作用,中介效应占总效应的22.90%。  相似文献   
125.
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   
126.
Integrity of both cerebral hemispheres is required to control in-phase or anti-phase coupling of ipsilateral hand and foot oscillations, as shown by the impairment of these tasks when performed on the healthy side of hemiplegic patients. On this basis, coupling of hand–foot movements was analysed in a right-handed subject (ME) who underwent a total resection of the corpus callosum. Oscillations of the prone hand and foot, paced by a metronome at different frequencies, as well as EMG activity in extensor carpi radialis (ECR) and tibialis anterior (TA) muscles were analysed by measuring the average phase difference between the hand and foot movements and EMG cycles.

ME performed in-phase movements (right-hand extension coupled to right-foot dorsal flexion) at frequencies up to 3 Hz, though the hand cycle progressively lagged the foot cycle as the frequency increased. At 3 Hz the hand lag reached −142° (as compared to about 25° in healthy subjects). The lag increased even further after application of an inertial load to the hand, reaching 180° at 1.8 Hz (about 50° in healthy subjects). ME's hand lag is caused by the lack of any anticipatory reaction in hand movers. In contrast to healthy subjects, which activate the ECR earlier than the TA when the frequency increases, ME activated the ECR later than TA at all frequencies higher than 0.9 Hz.

Anti-phase movements (hand extension coupled to foot plantar flexion) were performed only upto 1 Hz in unloaded conditions. At 0.6 Hz, movements were in tight phase-opposition (3°), but at 1 Hz, the hand lag reached −34° because of a delayed ECR activation. After hand loading ME was unable to couple movements in anti-phase. In contrast, normal subjects maintain a tight anti-phase coupling up to 2.0 Hz, both with an unloaded or loaded hand. Similar deficits were observed by ME when performing in-phase and anti-phase coupling on the left side, as well as when he was blindfolded.

In normal subjects, an anticipated muscular activation of hand movers compensates for hand loading. Since this compensation must depend on monitoring the hand delay induced by loading, the absence in ME of such compensatory reaction suggests that callosal division had apparently compromised the mechanisms sustaining feedback compensation for differences in the biomechanical limb properties. They also confirm and reinforce the idea that elaboration of the afferent message, aiming at controlling the phase of the movement association, needs the co-operation of both cerebral hemispheres.  相似文献   

127.
Functional magnetic resonance imaging (fMRI) is used to study brain function during behavioral tasks. The participation of pediatric subjects is problematic because reliable task performance and control of head movement are simultaneously required. Differential reinforcement decreased head motion and improved vigilance task performance in 4 children (2 with behavioral disorders) undergoing simulated fMRI scans. Results show that behavior analysis techniques can improve child cooperation during fMRI procedures.  相似文献   
128.
The transformation of functions refers to the untrained acquisition of stimulus functions among members of stimulus equivalence classes or relational frames. Although it is widely assumed that contextual control over the transformation of fuctions must exist, this has not yet been conclusively demonstrated in laboratory studies. Four experiments are reported in which (a) stimulus equivalence classes were established, (b) a conditional stimulus function was trained for one member of each of the classes, and (c) multiple-exemplar procedures were used to train and test for contextual control over the transformation of the stimulus function within the classes and to assess whether it generalized to new equivalence classes. Although a significant amount of training was required, the procedures ultimately resulted in the contextual control of function transformation for 9 of 10 participants and generalized contextual control for 4 of 5 participants.  相似文献   
129.
We examine the hypothesis that the efficiency of executive control processes is less stable over time in older than younger adults. An age-related decrease in the efficiency of executive control should result in an increase in performance variability in task conditions requiring the recruitment of executive control processes and not in task conditions requiring minimal involvement of executive control. Performance variability was similar for younger and older adults in task conditions requiring minimal executive control and greater for older than younger adults in task conditions requiring executive control. These and other data are consistent with the proposal that aging is associated with a decrease in the stability of executive control over time.  相似文献   
130.
Rejuvenescence has long been a topic of legend and medicine. As the body became the property of medical science, speculative fiction asked how fantastic experiments with bodies would affect the life course. In science fiction, medical breakthroughs promise or threaten to forestall or even reverse the decline from midlife through old age to senility and decrepitude. Responding to debates over evolution, eugenics, and scientific experimentation with human and animal subjects, rejuvenescence novels such as Bruce Sterling's Holy Fire (1996) ask readers whether they desire long life or heightened quality of life; the consolations of age or the hungers of youth; short-lived intensity or perpetual ennui.  相似文献   
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