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251.
Roger J. Ingham Yuedong Wang Janis C. Ingham Anne K. Bothe Scott T. Grafton 《Brain and language》2013
Developmental stuttering is known to be associated with aberrant brain activity, but there is no evidence that this knowledge has benefited stuttering treatment. This study investigated whether brain activity could predict progress during stuttering treatment for 21 dextral adults who stutter (AWS). They received one of two treatment programs that included periodic H215O PET scanning (during oral reading, monologue, and eyes-closed rest conditions). All participants successfully completed an initial treatment phase and then entered a phase designed to transfer treatment gains; 9/21 failed to complete this latter phase. The 12 pass and 9 fail participants were similar on speech and neural system variables before treatment, and similar in speech performance after the initial phase of their treatment. At the end of the initial treatment phase, however, decreased activation within a single region, L. putamen, in all 3 scanning conditions was highly predictive of successful treatment progress. 相似文献
252.
Although fluid intelligence and complex learning are conceptualized differently and assessed by apparently different measures, both theoretical accounts and empirical evidence suggest a relationship between the two constructs. In this study, major working memory aspects including the storage capacity and executive attention were proposed to account for the relationship between fluid intelligence and complex learning. A sample of 184 participants completed fluid intelligence and complex learning scales, as well as working memory measures that each included two or three treatment levels differing in the demands on capacity or executive control. The differences among the treatment levels provided a favorable precondition for employing fixed-links models to separate the core processes of storage capacity or executive attention from the auxiliary processes. Results indicated that both storage capacity and executive attention contributed significantly to fluid intelligence and complex learning. A further analysis showed that the two working memory aspects, particularly the storage capacity, accounted for most of the shared variance between fluid intelligence and complex learning. 相似文献
253.
The United States has made a significant effort and investment in STEM education, yet the size and the composition of the STEM workforce continues to fail to meet demand. It is thus important to understand the barriers and factors that influence individual educational and career choices. In this article, we conduct a literature review of the current knowledge surrounding individual and gender differences in STEM educational and career choices, using expectancy–value theory as a guiding framework. The overarching goal of this paper is to provide both a well-defined theoretical framework and complementary empirical evidence for linking specific sociocultural, contextual, biological, and psychological factors to individual and gender differences in STEM interests and choices. Knowledge gained through this review will eventually guide future research and interventions designed to enhance individual motivation and capacity to pursue STEM careers, particularly for females who are interested in STEM but may be constrained by misinformation or stereotypes. 相似文献
254.
Xiuyan Guo Li Zheng Hongyi Wang Lei Zhu Jianqi Li Qianfeng Wang Zoltan Dienes Zhiliang Yang 《Brain and cognition》2013
Past researches showed that empathy for pain not only triggers a resonance mechanism between other and self, but also is modulated by contextual factors. Using functional magnetic resonance imaging, the present study demonstrated that short-term media violence exposure reduced both pain ratings and also the activation of anterior insula and anterior mid-cingulate cortex to other’s pain. Thus, violence exposure modulated empathic responses to other’s pain based on a physiological desensitization. 相似文献
255.
Xiao Wang 《Psychology & health》2013,28(7):800-817
Objective : Because interpersonal discussion about condom use can encourage subsequent condom use, this project aims to examine the psychological antecedents of intentions to discuss or request the use of condoms with a sexual partner. Method : The data were collected from 849 heterosexual college students in the USA through an online survey. The survey contained several measures related to attitude functions (i.e. motivations), efficacy, norms and intentions to discuss condom use with a sexual partner. Results : Participants’ attitude functions weakly predicted intentions to discuss condom use. Communication efficacy was a more important predictor of intentions for females (vs. males) and for those in other relationships or not in a relationship (vs. long-term monogamous relationships). Anticipated negative emotions were a stronger predictor of intentions for those in long-term monogamous relationships (vs. other relationships or not in a relationship). Implications : Future research needs to consider more detailed attitude functions and anticipated emotions. Furthermore, background variables (e.g. gender and relationship status) can be moderators in addition to being distal predictors. 相似文献
256.
Jian-Ying Zhan Kim Cornish Jie Shao Chun-Hong Xie Yan-Xia Wang 《Child neuropsychology》2013,19(1):82-95
Attention is a complex domain that has reawakened research interest in recent years. There are relatively few studies that have examined age-related changes across different attention subcomponents, such as selection, maintenance, and control, using large samples covering a wide age range. The present study assessed performance in 466 participants in order to identify the ages at which mature performance was reached across differing attention subcomponents. Furthermore, we investigated whether the nature of the attentional demands or task difficulty predicted the age at which stable levels of performance were reached. The results supported the former rather than the latter alternative. 相似文献
257.
Y. Wang S.L. Shang H. Zhang L.-Q. Chen Z.-K. Liu 《Philosophical Magazine Letters》2013,93(12):851-859
To understand the Invar anomalies, such as negative thermal expansion and spontaneous magnetization, we have applied our recently developed thermodynamic framework for a system with itinerant-electron magnetism to the ordered Fe3Pt. The framework has coherently predicted the finite temperature intermixing between the fully ferromagnetic (FM) configuration and the spin-flipping configurations (SFCs). We have also discovered a tri-critical point at which a high-temperature second-order phase transition, between the fully ordered FM phase and the paramagnetic phase which is disordered due to SFCs, becomes first order at low temperatures. 相似文献
258.
The electrostatic potential and associated space charge across a 24°, [001] tilt boundary of SrTiO3 ceramic have been determined using electron holography. The results reveal a positive charged interface with a negative space charge on either side. The form of the double Schottky barrier and the local charge-density distribution at the interface are derived from the results. 相似文献
259.
Experimental results relating to the plateau behaviour in the cyclic stress-strain (CSS) curve of copper single crystals located on different sides of the stereographic triangle are summarized. Unlike the situation for single-sliporiented crystals, the crystallographic orientation has a strong effect on the plateau behaviour in the CSS curves of double- and multiple-slip-oriented crystals. The existence or non-existence of a plateau in the CSS curves, as well as the corresponding plateau stress amplitude, depend not only on the modes and intensities of dislocation interactions among slip systems operating in the crystals but also on the slip deformation characteristics associated with crystal orientations. The plateau region in CSS curve disappears only when multiple slip plays a determining role during cyclic deformation. 相似文献
260.
Tae Wook Heo Yi Wang Saswata Bhattacharya Xin Sun Shenyang Hu Long-Qing Chen 《Philosophical Magazine Letters》2013,93(2):110-121
We propose a phase-field model for modeling microstructure evolution during deformation twinning. The order parameters are proportional to the shear strains defined in terms of twin plane orientations and twinning directions. Using a face-centered cubic Al as an example, the deformation energy as a function of shear strain is obtained using first-principle calculations. The gradient energy coefficients are fitted to the twin boundary energies along the twinning planes and to the dislocation core energies along the directions that are perpendicular to the twinning planes. The elastic strain energy of a twinned structure is included using the Khachaturyan's elastic theory. We simulated the twinning process and microstructure evolution under a number of fixed deformations and predicted the twinning plane orientations and microstructures. 相似文献