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281.
Longing can be defined as a blend of the primary emotions of happiness and sadness. These primary emotions are experienced very early by children, and the meanings of the words happiness and sadness are also known by children early in their verbal development. To find out at what age children are able to understand and use the more developed concept of longing, the authors interviewed 74 preschoolers (4- and 5-year-olds) in Norway and Sweden about their experiences of longing. Chi-square analyses showed age and sex differences in knowledge of the concept, and some differences between categories of longing were also significant. Results showed that young children's ability to understand and use the concept of longing appears to be limited and that girls seem to mature earlier in this respect than boys do.  相似文献   
282.
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   
283.
Olivopontocerebellar atrophy (OPCA) is a still debated condition, of which motor disruption is the most common feature. A high incidence of associated mood disorders may exist, but there are few studies on concomitant cognitive impairment. Our aim was to assess whether there is reading and writing disruption in olivopontocerebellar atrophy (OPCA). 6 patients were administered different reading and writing tasks. Scores were then compared to those obtained by healthy volunteers. There was an evident impairment in reading and writing execution in our patients compared to those of the control group. On the contrary, no difference could be found in abstraction, problem-solving, and memory tasks. We discuss the results, debating the role of the cerebellum in the conscious process of cognition or in ocular movement control (necessary for reading and writing fluidity and effective execution) and in the dynamic activation of all the cerebral cortex mediated by the diffuse projection to the reticular system.  相似文献   
284.
The Serial Color-Word Test was administered to nonclinical volunteers of three age strata (17-29, 30-45, 46-65 yr.). Sex differences on the 17 variables of the test were explored for each age stratum. Only six significant intersex differences were found. In all age strata women scored significantly higher on linear regression of reading times in one of the last two subtests, i.e., R4 or R5.  相似文献   
285.
This study describes a method of modeling human trunk and whole body backward bending and suggests a possible neural control strategy. The hypothesis was that the control system can be modeled as a linear feedback system, in which the torque acting at a given joint is a function of the state variables (angular positions and angular velocities). The linear system enabled representation of the feedback system by a gain matrix. The matrix was computed from the kinematics recorded by a movement analysis system and from the joint torques calculated by inverse dynamics. To validate the control model, a comparison was made between the angular kinematics yielded by the model and the experimental data. Moreover, for all subjects, the same relationships between feedback coefficients were found although gain values were different. The study showed that the feedback system is an appropriate model of the strategy from performing an accurate controlled trunk or whole body backward bending in the sagittal plane.  相似文献   
286.
In a dual-task situation, peripheral perception can deteriorate due to different variables related to the experimental situation, such as central task complexity and the relative priority given to the two tasks. Recent studies have also shown that individual characteristics (such as the state of vigilance) can alter the useful visual field. The ability to perceive signals presented at different places in the visual field decreases in situations that lead to episodes of low vigilance. In Exp. 1, 27 subjects (18-29 years) had to perform a monotonous and prolonged dual-monitoring task involving central and peripheral vision. The test was carried out with two different sets of instructions regarding priority: the more important task was either the central task or the peripheral one. In Exp. 2, 18 subjects (18-30 years) performed the same test, but this time with two levels of complexity of the central task, either a simple monitoring activity or the same monitoring task coupled with a counting activity. Elliptical interpolation of the data enabled assessment of the deformation of the useful visual field in both experiments. The analysis of the parameters of the elliptical model indicated that the useful visual field mainly shrinks on the vertical axis, as the individual becomes drowsy. The useful visual field also shrinks on the horizontal axis when the peripheral task has priority and the monitoring activity is prolonged, or when the central task is complex.  相似文献   
287.
The effects of the color of a personal computer screen on work performance, psychological mood, and autonomic response were investigated. 24 subjects were asked to perform visual tasks presented on the computer display. Three types of computer monitor, which were colored red, blue, or beige, were employed to present visual cognitive tasks. The mood measure, the Japanese Stress Arousal Check List, and heart rate measurement were administered before and after work on each color of computer monitor. Analysis of a low-demand task (Exp. 1) showed that the red computer monitor reduced visual task performance compared to that with the blue, while the blue monitor decreased visual task performance on a high-demand task (Exp. 2). The color of the monitor did not affect mood or heart rate. Based on these findings, the effect of the color of environmental cues on work was discussed.  相似文献   
288.
Cognitive deficits in major depression   总被引:4,自引:0,他引:4  
Major depression is a mood disorder that is often accompanied by the impairment of cognitive functions. Although suggestive, the large range of existing neuropsychological, neuropsychiatric, and, lately, neuroimaging investigations have not yet given a consistent picture of the psychological and biological disturbances involved in this psychiatric disorder. The present study of the cognitive functions in depression was part of an extensive investigation, including neuropsychological testing, psychiatric examination, and neuroimaging. A representative sample of 40 severely depressed hospitalized patients and a group of 49 closely matched control subjects were tested with an extensive neuropsychological test battery. Results, corrected for various confounding factors, confirmed the current notion that depressed patients suffer from wide-spread cognitive impairments. The group analysis did not allow any hypothesis on a possible pattern to the dysfunctions, but heterogeneity in the test performances calls for further analysis of the data in patient subgroups in relation to neuroimaging results.  相似文献   
289.
Past research has examined the stress resiliency of individuals high in sense of personal-mastery. However, it has been theorized that within more collectivist cultures, a sense of shared efficacy, which we call communal-mastery, may be more central to people's resiliency in the face of challenging life circumstances. We compared the impact of sense of self-mastery (i.e., I am the key to my success) to that of communal-mastery (i.e., I am successful by virtue of my social attachments) in a prospective study among a group of rural 103 Native American women residing on Indian Reservations in Montana. We found that women high in communal-mastery experienced less increase in depressive mood and anger, especially when faced with high stress circumstances, than women who were low in communal-mastery. In addition, the beneficial impact of communal-mastery was found to be more effective than self-mastery for these women.  相似文献   
290.
The time course of competition for attention: attention is initially labile   总被引:8,自引:0,他引:8  
Competition for attention between 2 written words was investigated by presenting the words briefly in a single stream of distractors (Experiment 1) or in different streams (Experiment 2-6), using rapid serial visual presentation at 53 ms/item. Stimulus onset asynchrony (SOA) was varied from 0 to 213 ms. At all SOAs there was strong competition, but which word was more likely to be reported shifted markedly with SOA. At SOAs in the range of 13-53 ms the second word was more likely to be reported, but at 213 ms, the advantage switched to the first word, as in the attentional blink. A 2-stage competition model of attention is proposed in which attention to a detected target is labile in Stage 1. Stage 1 ends when one target is identified, initiating a serial Stage 2 process of consolidation of that target.  相似文献   
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