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901.
In this article the authors report on a study of the experience of unemployment. The emphasis is on those factors that unemployed people found helpful and those that hindered them. 相似文献
902.
In two experiments, a speeded sorting task was administered to children. In each sorting, the child was instructed to sort a deck of cards according to values on one dimension while the values of a second irrelevant dimension were held constant, were correlated, or were varied orthogonally. Experiment 1 evaluated developmental changes in perceived structure as compared with such changes in the control of attention. Different groups of kindergarten, 2d-, and 5th-grade children performed the task with spatially integrated vs spatially separated dimensions. The results indicate that with spatially integrated dimensions there is a trend from holistic to featural perception and an increase in attentional control with increasing age. Spatially separate dimensions are perceived dimensionally at all ages, but show a trend in attentional development. In Experiment 2, the spatially integrated dimensions of Experiment 1 were made separable by portraying different targets within a configuration in different colors. The theoretical implications of the results are discussed. 相似文献
903.
This study examined the relationships between metamemory and strategic behavior in impulsive and reflective children. One hundred thirty children from the fourth, fifth, and sixth grades participated. Seventy-seven of these children had been tested 3 years earlier on metamemory and cognitive tempo tasks. At pretraining, children were assessed on metamemory, cognitive tempo, summarization skills, and teacher ratings of impulsive behavior in the classroom. Next, children in three experimental groups received prose summarization instructions, summarization instructions in conjunction with metacognitive training about the importance of a reflective approach to learning, or no instructions. Following training, children were again measured on tempo, summarization skills, and teacher ratings of impulsivity. Analyses of strategy maintenance data indicated superior performance for children who had received both summarization and metacognitive training. Causal modeling analyses showed that early metamemory was an antecedent of later strategy acquisition. The dual role of metacognition as a precursor of later strategy acquisition and controller of lower level strategies was highlighted. 相似文献
904.
Differences in academic performance at school depending on handedness: matter for neuropathology? 总被引:1,自引:0,他引:1
S M Williams 《The Journal of genetic psychology》1987,148(4):469-478
Two studies found that left-handed children had significantly poorer academic records than did right-handed children, though the effect was small. Study 1 provided evidence that, for some academic disciplines, the important difference appeared to be between those children whose family history of handedness was concordant with their own handedness and those children whose family history of handedness was discordant with their own handedness. The inclusion of gender in asymmetry research was bolstered by Study 2. When predicting idiosyncrasies in left-handers' cognitive performance, it should be borne in mind that left-handers form a minority group as well as a neurologically distinct one. 相似文献
905.
A S Westman 《The Journal of genetic psychology》1987,148(3):259-270
To investigate the role of perception and stress on time concepts, the real-time and apparent durations of common events varying in length from 30 s to 4 years were rated by kindergarten through 12th-grade pupils, college students, professors, and stress-impaired adults (N = 1,788). The events were pleasant, neutral or unpleasant; either directly perceptible and of specific duration or perceptually vague; and happened either to oneself or to someone else. Second graders differentiated apparent from real-time durations and, therefore, already had an abstract concept of time. As predicted from differentiation theory (Gibson, E. J., 1969; Gibson, J. J., 1966, 1983), longer durations were acquired later than shorter ones; perceptually-vague durations were acquired later than clearly perceptible ones of similar length; and, as Neisser (1976) also suggested, stress did not lead to regression, nor did the personal-impersonal dimension make a difference during childhood. 相似文献
906.
Fantasy proneness and psychopathology 总被引:1,自引:0,他引:1
Fantasy prone persons ("fantasizers") selected from "normal" populations report experiences associated with psychopathology in clinical populations (e.g., fantasies that reach hallucinatory proportions, difficulty discriminating reality from fantasy). In Study 1, we administered objective (MMPI) and projective (Rorschach) measures to high fantasy prone individuals (upper 4% of college population), medium fantasy prone individuals (middle range), and nonfantasizers (lowest 4%). Subjects who were fantasizers appeared to use fantasy for defensive or adaptive purposes compared with others and produced 8/9 modal code types on the MMPI. On the basis of the MMPI findings, a subset of fantasizers could be described as exhibiting a significant degree of psychopathology. In Study 2, a second sample of fantasy prone individuals could not be distinguished from comparison groups in contacts with professionals for help with psychological problems, use of psychotropic medication, or number of close friendships. Although fantasizers perceived themselves as less well adjusted than comparison subjects and reported greater difficulty in distinguishing fantasy from reality, most fantasizers rated their psychological functioning as adequate and above and did not differ from less fantasy prone subjects in ratings of positivity of self-concept. As demonstrated in Study 1, a subset of fantasizers did appear to be more pathological than other subjects were, with three fantasizers reporting a history of psychiatric hospitalizations. It is estimated that between 10 and 20% of fantasizers exhibit significant signs of maladjustment/psychopathology; however, as a rule, fantasy proneness does not appear to be antecedent to severe manifestations of psychopathology. 相似文献
907.
There are wide individual differences in the characteristic intensity of affective response to the same emotion-evoking event. The processes whereby individuals come to experience strong or mild emotional responses when exposed to the same affect-provoking stimuli are still unclear. In these studies, we propose that individual differences in affect intensity are associated with certain cognitive operations used during exposure to emotion-relevant stimuli. Specifically, cognitive operations that involve personalizing, generalizing, and selective abstraction were hypothesized to discriminate subjects high and low in affect intensity. Two studies replicated support for the hypothesis that subjects high on the affect-intensity dimension engage in more personalizing/empathic and more generalizing/elaborative cognitive operations than do subjects low on the affect-intensity dimension. The same cognitive operations discriminated groups high and low in affect intensity in response to both positive and negative emotional stimuli. Also, the cognitions that discriminated subjects high and low in affect intensity occurred only in response to affective stimuli; neutral stimuli did not evoke divergent cognitive operations for these two groups. Finally, a high degree of consistency was found in the use of emotion-relevant cognitive operations across positive and negative affective stimuli. 相似文献
908.
Modulation of the responses to perturbation applied during different phases of three rhythmic movements in humans-running, cycling, and hopping-was studied. The perturbation was an electrical stimulus. The results showed gating and modulation of the responses in both ipsi- and contralateral limb muscles. The responses during running and cycling were only excitatory in nature, while during hopping an inhibitory response was observed. These responses were not correlated with the normal activity during the movement. The latency of the response in general was not altered for different stimulation phases. The alterations in the step cycle demonstrated overt behavioral changes due to the responses. There were differences between the responses observed during these movements and walking. In running, the major adaptation to perturbations appears to be in the contralateral side as seen in the changes in the step cycle. During cycling (except for one phase) and hopping, the same set of muscles was activated in response to perturbation. This represents a simplifying strategy in response organization. The dependency of the response on the task characteristics, postural stability requirement, and external constraints imposed on the subject is discussed. These studies provide insights into task-dependent strategies adopted by the nervous system to meet unexpected perturbation during rhythmic movements in humans. 相似文献
909.
S J McKelvie 《Perceptual and motor skills》1987,65(2):388-390
Subjects viewed upright photographs of faces, then attempted to recognize them unchanged, vertically reversed or inverted. In two of four conditions, hit scores were lower for inverted than vertically reversed faces, suggesting that lateral reversal is a meaningful component of inversion. The effect was not sufficiently strong, however, to overcome a generally high false-alarm rate for upside-down faces. 相似文献
910.
It has been suggested that the hypnotic state results in a greater relative activation or priming of the right cerebral hemisphere than of the left hemisphere. The experiment reported here employed hypnosis to produce such a priming effect in a visual-detection task. Subjects were required to detect the presence or absence of a gap in outline squares presented either to the left visual field or right visual field, with response time as the primary dependent measure. Those subjects who were hypnotized produced a 50-msec. response time difference favoring squares presented to the left visual field whereas control subjects and simulator-control subjects showed no lateral asymmetries. The result is classified as a material-nonspecific priming effect and discussed with regard to the nature of processing resources. 相似文献