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1.
Two experiments were conducted to examine the effect of absolute-pitch possession on relativepitch processing. Listeners attempted to identify melodic intervals ranging from a semitone to an octave with different reference tones. Listeners with absolute pitch showed declined performance when the reference was out-of-tune C, out-of-tune E, or F#, relative to when the reference was C. In contrast, listeners who had no absolute pitch maintained relatively high performance in all reference conditions. These results suggest that absolute-pitch listeners are weak in relative-pitch processing and show a tendency to rely on absolute pitch in relative-pitch tasks.  相似文献   
2.
In accelerated longitudinal design, one samples multiple age cohorts and then collects longitudinal data on members of each cohort. The aim is to study age-outcome trajectories over a broad age span during a study of short duration. A threat to valid inference is the Age x Cohort interaction effect. S. W. Raudenbush and W. S. Chan (1993) developed a test for such interactions in the context of 2 cohorts by using a hierarchical model. The current article extends this approach to include any number of cohorts. Using the National Youth Survey, the authors combine data collected on 7 cohorts over 5 years to approximate change in antisocial attitudes between 11 and 21 years of age. They show how to test for cohort differences in trajectories, how to calculate the power of the test, and how to use graphical procedures to aid understanding. The approach allows unbalanced designs and the clustering of participants within families, neighborhoods, or other social units.  相似文献   
3.
The neuronal system to process and transfer auditory information to the higher motor areas was investigated using fMRI. Two different types of internal modulation of auditory pacing (1 Hz) were combined to design a 2×2 condition experiment, and the activation was compared with that under a visual guidance. The bilateral anterior portion of the BA22 (ant-BA22) and the left BA41/42 were more extensively activated by the combined modulation condition under the auditory cue than that under the visual cue. Among the four auditory conditions with or without the two types of internal modulation, the activation in the ant-BA22 was augmented only on the left side by the combined modulation condition. The left ant-BA22 may be especially involved in integrating the external auditory cue with internal modulation, while the activation on the right side did not depend on the complexity. The role of the left BA41/42 in motor regulation may be more specific to the processing of an auditory cue than that on the right side. These two areas in the left temporal lobe may be organized as a subsystem to handle the timing of complex movements under auditory cues, while the higher motor areas in the frontal lobe support both sensory modalities for the cue. This architecture may be considered as ‘audio-motor control’, which is similar to the visuo-motor control of the front-parietal network.  相似文献   
4.
Empirical evidence suggests that three-dimensional (3D) images of nature promote physiological relaxation in humans by providing more realistic effects compared with two-dimensional (2D) images. However, no studies have evaluated the physiological relaxation effects of nature-derived 3D images on prefrontal cortex and autonomic nerve activity. The present study aimed to clarify the physiological relaxation effects of visual stimulation by 3D flower images on prefrontal cortex and autonomic nerve activity. Nineteen male university students (22.2 ± 0.6 years) were presented with 3D and 2D images of the water lily for 90 s. Prefrontal cortex activity was measured using near-infrared spectroscopy, while autonomic nerve activity was measured using heart rate variability (HRV). Psychological effects were determined using a modified semantic differential method (SD). Compared with visual stimulation by 2D images, that by 3D images resulted in a significant decrease in oxyhemoglobin concentration in the right prefrontal cortex, lower sympathetic activity as calculated by the ratio of the low-frequency to high-frequency HRV component, and a significantly greater realistic feeling as evidenced by higher SD ratings. In conclusion, visual stimulation by realistic 3D floral images promotes physiological relaxation more effectively than the corresponding 2D image.  相似文献   
5.
It remains unclear whether activation kinetics in the motor cortex area is affected by training. The purpose of the present study was to examine the effect of training on the motor cortex activation. To accomplish this, the correlation between maximal voluntary contraction and motor cortex (M1) activity was examined. Differences in the motor cortex activation between two groups during exercise were examined in 14 male volunteer participants (M age 25.2 yr., SD = 1.4): seven highly trained athletes (VO2max = 60 ml/kg/min.; maximal voluntary contraction > 55 kg, M MVC = 63.6 kg, SD = 4.2) and seven nonathletes (VO2max < 45 ml/ kg/min.; MVC < 50.0 kg, M MVC = 4 3.5 kg, SD = 5.2). Participants were familiarized with the study protocol during which they performed a maximal voluntary static handgrip test. Specifically, M1 activation was measured by near-infrared spectroscopy throughout a handgrip exercise in which participants performed a sustained middle-intensity handgrip exercise (50% of maximal voluntary contraction) until voluntary exhaustion. In the Athlete group, activation in the M1 at voluntary exhaustion fell below the resting value. In the Nonathlete group, activation in the M1 was elevated throughout the exercise. Results suggest that motor signals from the motor cortex area correlate with exercise training status, especially during fatiguing exercise.  相似文献   
6.
Musically trained listeners compared a notated melody presented visually and a comparison melody presented auditorily, and judged whether they were exactly the same or not, with respect to relative pitch. Listeners who had absolute pitch showed the poorest performance for melodies transposed to different pitch levels from the notated melodies, whereas they exhibited the highest performance for untransposed melodies. By comparison, the performance of melody recognition by listeners who did not have absolute pitch was not influenced by the actual pitch level at which melodies were played. These results suggest that absolute-pitch listeners tend to rely on absolute pitch even in recognizing transposed melodies, for which the absolute-pitch strategy is not useful.  相似文献   
7.
The kynurenine (KYN) pathway, which is initiated by indoleamine 2,3-dioxygenase, is the main tryptophan (TRP) metabolic pathway. It shares TRP with the serotonin (5-HT) pathway. We investigated the influence of inescapable-predator (rat) stress on behavior and brain TRP metabolism in mice. Male ICR mice (4W) were exposed to 20-min inescapable-predator stress. Behavior on an elevated plus-maze, and TRP, KYN, and 5-HT levels in the prefrontal cortex, hippocampus, amygdala, and dorsal raphe nuclei were measured 1 and 4 weeks after stress exposure. Predator stress increased the number of open-arm entries (NOA) 4 weeks after stress exposure without altering the number of closed-arm entries (NCA). Thus, the open/closed-arm entry ratio (NOA/NCA) increased after stress exposure. Predator stress increased KYN levels in the prefrontal cortex (until 4 weeks after stress exposure) and dorsal raphe nuclei (for 1 week after stress exposure), decreased 5-HT levels in all brain regions (until 4 weeks after stress exposure). Thus, predator stress increased the KYN/5-HT ratio in all regions, in particular in the prefrontal cortex and hippocampus until 4 weeks after stress exposure. Predator stress shifted the balance between the KYN and 5-HT pathways to the KYN pathway, and induced behavioral disinhibition.  相似文献   
8.
Although D-cycloserine (DCS), a partial agonist of the N-methyl-d-aspartate (NMDA) receptor, and valproic acid (VPA), a histone deacetylase inhibitor, have been investigated for their roles in the facilitation of emotional learning, the effects on non-emotional declarative and procedural learning have not been clarified. We performed a randomized, blind, placebo-controlled, 4-arm clinical trial to determine the effects of DCS and VPA on the overnight properties of declarative and procedural learning in 60 healthy adults. Subjects were orally administrated a placebo, 100 mg DCS, 400 mg VPA, or a combination of 100 mg DCS and 400 mg VPA before they performed declarative and procedural learning tasks. Subjects then had their performance retested the following day. We observed that DCS facilitated procedural but not declarative learning and that VPA did not contribute to learning. Surprisingly, however, VPA attenuated the enhancement effect of DCS when coadministered with it. These results suggest that DCS acts as an enhancer of hippocampus-independent learning and that VPA may have an extinguishing pharmacological effect on excitatory post-synaptic action potentials that NMDA receptors regulate within procedural learning.  相似文献   
9.
In Item Response Theory (IRT), item characteristic curves (ICCs) are illustrated through logistic models or normal ogive models, and the probability that examinees give the correct answer is usually a monotonically increasing function of their ability parameters. However, since only limited patterns of shapes can be obtained from logistic models or normal ogive models, there is a possibility that the model applied does not fit the data. As a result, the existing method can be rejected because it cannot deal with various item response patterns. To overcome these problems, we propose a new semiparametric IRT model using a Dirichlet process mixture logistic distribution. Our method does not rely on assumptions but only requires that the ICCs be a monotonically nondecreasing function; that is, our method can deal with more types of item response patterns than the existing methods, such as the one-parameter normal ogive models or the two- or three-parameter logistic models.  相似文献   
10.
It is shown that the normal modal logic of two reflexive points jointed with a symmetric binary relation splits the lattice of normal extensions of the logic KTB. By this fact, it is easily seen that there exists the third largest logic in the class of all normal extensions of KTB. Presented by Michael Zakharyaschev Received February 17, 2006  相似文献   
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