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891.
General intelligence, the g factor, is a major issue in psychology and neuroscience. However, the neural mechanism of the g factor is still not clear. It is suggested that the g factor should be non-modular (a property across the brain) and show good colinearity with various cognitive tests. This study examines the hypothesis that functional connectivity may be a good candidate for the g factor. We recorded resting state eyes-closed EEG signals in 184 healthy young females. Coherence values of 38 selected channel pairs across delta, theta, alpha, beta and gamma frequencies were correlated with six intelligence quotient (IQ) subtests, including symbol search, block design, object assembly, digit span, similarity and arithmetic. A three-stage analytic flow was constructed to delineate common (g factor) and unique neural components of intelligence. It is noticed that the coherence pattern demonstrates good correlation with five of the IQ subtests (except symbol search) and non-modularity in the brain. Our commonality analyses support connectivity strength in the brain as a good indicator of the g factor. For the digit span and arithmetic tests, the uniqueness analyses provide left-lateralized topography relevant to the operation of working memory. Performance on the arithmetic test is further correlated with strengths at left temporo-parietal and bilateral temporal connections. All the significant correlations are positive, indicating that the stronger the connectivity strengths, the higher the intelligence. Our analyses conclude that a smarter brain is associated with stronger interaction in the central nervous system. The implication and why the symbol search does not show parallel results are discussed. 相似文献
892.
Wang L Ross CA Zhang T Dai Y Zhang H Tao M Qin J Chen J He Y Zhang M Xiao Z 《Journal of personality disorders》2012,26(3):393-401
The objective of this study was to investigate the frequency, clinical characteristics, and comorbidity of borderline personality disorder (BPD) among psychiatric outpatients in two clinics at Shanghai Mental Health Center. A cross-sectional investigation was conducted. From 3,075 outpatients screened using the Personality Diagnostic Questionnaire-IV+, 2,284 patients positive for a personality disorder were assessed using the Structured Clinical Interview for DSM-IV Personality Disorders. The frequency of BPD among the psychiatric outpatients was 5.8%, with a frequency of 3.5% among males and 7.5% among females (p < .01). BPD was found to have extensive comorbidity with Axis I and II disorders. This study proves that BPD does occur in China. The detected frequency among outpatients is lower than that reported in North America. 相似文献
893.
Early predictors of high school mathematics achievement 总被引:1,自引:0,他引:1
Siegler RS Duncan GJ Davis-Kean PE Duckworth K Claessens A Engel M Susperreguy MI Chen M 《Psychological science》2012,23(7):691-697
Identifying the types of mathematics content knowledge that are most predictive of students' long-term learning is essential for improving both theories of mathematical development and mathematics education. To identify these types of knowledge, we examined long-term predictors of high school students' knowledge of algebra and overall mathematics achievement. Analyses of large, nationally representative, longitudinal data sets from the United States and the United Kingdom revealed that elementary school students' knowledge of fractions and of division uniquely predicts those students' knowledge of algebra and overall mathematics achievement in high school, 5 or 6 years later, even after statistically controlling for other types of mathematical knowledge, general intellectual ability, working memory, and family income and education. Implications of these findings for understanding and improving mathematics learning are discussed. 相似文献
894.
<正>一、前言周敦颐继承了隋唐五代以来儒释道三教融合的开阔学风。从他的人生历程来看,他既有儒家入仕传统的一面,也有由庄子所开启的文人传统的一面。①作为一位由士入仕的儒者,周敦颐支持范仲淹 相似文献
895.
896.
897.
Bistable figures provide a fascinating window through which to explore human visual awareness. Here we demonstrate for the first time that the semantic context provided by a background auditory soundtrack (the voice of a young or old female) can modulate an observer's predominant percept while watching the bistable "my wife or my mother-in-law" figure (Experiment 1). The possibility of a response-bias account-that participants simply reported the percept that happened to be congruent with the soundtrack that they were listening to-was excluded in Experiment 2. We further demonstrate that this crossmodal semantic effect was additive with the manipulation of participants' visual fixation (Experiment 3), while it interacted with participants' voluntary attention (Experiment 4). These results indicate that audiovisual semantic congruency constrains the visual processing that gives rise to the conscious perception of bistable visual figures. Crossmodal semantic context therefore provides an important mechanism contributing to the emergence of visual awareness. 相似文献
898.
Lin TW Chen SJ Huang TY Chang CY Chuang JI Wu FS Kuo YM Jen CJ 《Neurobiology of learning and memory》2012,97(1):140-147
Different exercise paradigms show differential effects on various forms of memory. We hypothesize that the differential effects of exercises on memory performance are caused by different neuroplasticity changes in relevant brain regions in response to different exercise trainings. We examined the effects of treadmill running (TR) and wheel running (WR) on the Pavlovian fear conditioning task that assesses learning and memory performance associated with the amygdala (cued conditioning) and both the amygdala and hippocampus (contextual conditioning). The skeletal muscle citrate synthase activity, an indicator of aerobic capacity, was elevated in rats received 4 w of TR, but not WR. While both TR and WR elevated the contextual conditional response, only TR facilitated the cued conditional response. Using a single-neuron labeling technique, we found that while both TR and MR enlarged the dendritic field and increased the spine density in hippocampal CA3 neurons, only TR showed these effects in basolateral amygdalar neurons. Moreover, both types of exercise upregulated synaptic proteins (i.e., TrkB and SNAP-25) in the hippocampus; however only TR showed similar effects in the amygdala. Injection of K252a, a TrkB kinase inhibitor, in the dorsal hippocampus or basolateral amygdala abolished the exercise-facilitated contextual or cued fear learning and memory performance, respectively, regardless of the types of exercise. In summary, our results supported that different types of exercise affect the performance of learning and memory via BDNF-TrkB signaling and neuroplasticity in specific brain regions. The brain region-specific neuronal adaptations are possibly induced by various levels of intensity/stress elicited by different types of exercise. 相似文献
899.
Mariners actively adjust their body orientation in response to ship motion. On a ship at sea, we evaluated relations between standing postural activity and the performance of a precision aiming task. Standing participants (experienced mariners) maintained the beam from a handheld laser on a target. Targets were large or small, thereby varying the difficulty of the aiming task. Targets were located in front of the participant or to the participant's right (requiring participants to look over the right shoulder), thereby varying the functional consequences (for the aiming task) of postural activity in different body axes. The torso was oriented toward the bow or toward the ship's side (athwartship), thereby varying the effects on postural activity of differential motion of the ship in its different axes. The weather was rough, producing high magnitudes of ship motion, which sometimes caused participants to step or stagger. Our manipulations influenced the magnitude and dynamics of head and torso movements, as well as the organization of movement in different axes. The results provide the first empirical confirmation that postural activity can be influenced by orientation of the torso relative to a ship. Despite powerful effects of ship motion, postural activity was influenced by variations in target location and in the difficulty of the aiming task, replicating subtle effects that have been observed on land. We discuss implications for hull design and the placement of workstations on ships. 相似文献
900.
Man Yee Ho Sylvia Xiaohua Chen Michael Harris Bond Chin Ming Hui Clare Chan Michael Friedman 《Journal of Happiness Studies》2012,13(3):565-578
Maintaining a satisfying heterosexual relationship is important to many individuals?? happiness and physical health. Evolutionary theories on the formation of relationships suggest that adult attachment and relationship commitment are universal mechanisms for securing and maintaining such mating relationships. This study sought to understand how these two mechanisms may link to each other and how they in turn contribute to relationship satisfaction with one??s current partner in Hong Kong Chinese and American cultures. Similarities in the model for relationship satisfaction were found among young dating couples in the United States and Hong Kong. Specifically, attachment anxiety was positively linked to structural commitment, whereas attachment avoidance was negatively related to personal commitment. Both dimensions of attachment (anxiety and avoidance) and both components of commitment (personal and structural) were found to predict current relationship satisfaction significantly and equivalently across cultures, with the pathway from attachment avoidance to current relationship satisfaction similarly mediated by personal commitment in both cultural groups. These results were interpreted in terms of a probable universal logic informing the interpersonal dynamics involving attachment and relationship commitment. 相似文献