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941.
Within the context of a prospective longitudinal research design, the structure of personality and initial levels of drug use were used to predict, multivariately, later drug use among male and female adolescents. The findings indicated that personality and belief measures of nonconventionality provide a significant increment in the prediction of later drug use beyond a level achieved by knowing initial usage rates. In addition, other personality and belief measures yield further increments in the prediction of subsequent drug use. Developmentally, the results revealed a differentiation of drug use patterns across the year's time, with one pattern primarily reflecting alcohol use, and a second pattern primarily reflecting use of marijuana and ‘hard’ drugs. While both patterns were related to measures of nonconventionality, certain personality features distinguished between them. Emergent use of marijuana and ‘hard’ drugs was related to depression, mistrust and attractiveness, while emergent alcohol use was related to generosity, ambition, agility and cheerfulness. These results were cross-validated in two samples of subjects. Implications of the findings for adolescent psychosocial development are discussed.  相似文献   
942.
Guzy and Axelrod investigated auditory attention switching by means of the click-counting paradigm and concluded that attention switching is a fatigable process. In the present comment it is shown that this conclusion is based on a faulty analysis of the data: The scores subjected to the analysis of variance were transformed such that they were no longer linear combinations of the factorial effects. Reanalyzing the data in the correct way renders perfectly linear conting functions that deviate from theoretical fatigue functions. It is concluded that the attention-switching mechanism is not fatigable.  相似文献   
943.
A serious methodological error was committed by Stephens et al. (1972), the protestations of the present critics notwithstanding. When studying the relationship between two sets of variables, it is clearly wrong to hold chonological age constant in one set and allow it to vary in the other. This error spuriously reduces the correlation between the two sets. A demonstration that the two sets define different first-order factors provides very little information about the degree of relationship present, which must be derived from the intercorrelations of those factors. In the original research, these were also biased by the methodological error. The conclusion of Humphreys and Parsons that Piagetian tasks and intelligence tests could be used interchangeably is reinforced. The hypothesis that the relatively small amount of unique variance in the Piagetian composite is relatively unimportant psychologically can only be discarded on the basis of good empirical research, not debater's arguments.  相似文献   
944.
Summary The results of video analysis of non-verbal interview behavior of patients with affective psychoses were discussed. Characteristic differences were shown for the left-right distribution of certain hand movement types in studies of normal subjects by Kimura (1973) with an essentially comparable technique. A neurodynamic interpretation of such findings was attempted. First we discussed the shortcomings of current neuropsychological interpretations and concluded that they present a challenge to establish a conceptual framework, which would permit the resolution of both neurodynamic and developmental points of view. Finally, we examined the heuristic value of such a conceptual framework. We noted that it is marked by the concept of inter-hemispheric coordination, and applied this concept to our findings as well as to hypotheses in depression research obtained by other methods.  相似文献   
945.
材料数量与呈现速度对视、听同时瞬时记忆的影响   总被引:3,自引:0,他引:3  
视、听材料同时识记、瞬时记忆效果并非普遍降低。材料数量影响视、听同时瞬时记忆效果的变化及其方向;无意义联系汉字数量超记忆广度时,视、听同时瞬时记忆相对效果与非同时识记相比提高。材料数量也影响视、听同时瞬时记忆的相对优势及重现方式。这些结果倾向于表明,材料数量在记忆广度内及超记忆广度时,视、听同时瞬时记忆的组织加工不同。呈现速度只影响记忆优势及重现方式。根据多项分析,可以认为视、听通道标签是组织视、听同时瞬时记忆最鲜明的标签,经过识记5个视、听同时字表,视、听同时识记效果有提高趋势。  相似文献   
946.
In this article, Yager and Hector argue that all people, including counselors, developmentally learn and subsequently act out a set of roles that includes both “real self” roles and other, less familiar, and more uncomfortable roles. They suggest that certain principles employed in the training of actors can be applied to counselor preparation. The authors briefly discuss relevant research and offer specific implications and suggestions for counselor educators.  相似文献   
947.
Economics, pressure for accountability and changing student needs are forcing counseling centers to evaluate their services and methods of delivery. This article illustrates how a developmental, proactive, outreach approach can be an alternative to the traditional medical model.  相似文献   
948.
Decision making is an important link in the central part of a reflex—the “mental element” according to Sechenov. The reflex nature of this mental process is revealed in experiments where a voluntary motor reaction is chosen unconsciously as a response to subliminal conditional visual stimuli. Thus, learning which is reflected by “advance” or prior decision making can be performed unconsciously through a conditional reflex. But, once elaborated, temporary connections are preserved only in shortterm memory. They are not transferred to long-term memory, as in the case of recognition of signals. Decision making, being the central mental part of the reflex, like any activity of the brain, is performed in time by a certain cortical structure. Analysis of P300 amplitudes shows that decision making is related to local activation of the frontal parts of the cerebral hemispheres. We suggest that the local activation of these areas is induced by conditional excitation of the neuronal mechanisms of focused attention. It provides a “command” to perform a voluntary motor reaction adequate to the conditions at hand. A large part of latency of voluntary motor response of man is spent on decision making, especially in discrimination of signals and in choice of reactions.  相似文献   
949.
Harvard Medical School and Peter Bent Brigham Hospital, Boston, Massachusetts 02115 The model treats the detection of targets in a visual search task as a concatenation of two serial detection stages. Preattentive visual mechanisms in the initial stage function as a filter, selecting specific features of a visual pattern for the observer’s explicit attention and final cognitive evaluation. The model uses bivariate normal distributions to represent the decision variables for the two serial stages, assuming different parameters for the target and nontarget features in a test set. The model is applied to the detection performance of radiologists interpreting chest x-rays under various conditions of search. It accounts for the substantial improvement in radiologists’ ability to distinguish between target and nontarget test features when they had to search the x-ray images, compared to their performance without visual search. A change in the ROC curve between two different search tasks could be interpreted as a shift in the selection cutoff used by the preattentive filter.  相似文献   
950.
Three experiments employing the McCollough paradigm were conducted to determine the spatial-frequency content of visual imagery. In Experiment 1, large and reliable pattern-contingent color aftereffects were obtained after adaptation to visual imagery. The direction of the aftereffects indicated that subjects were adapting to higher spatial frequencies in their imagery. These results contrast with the data of Experiment 2, which demonstrate that color aftereffects obtained with adaptation to physically present stimuli are mediated by the fundamental spatial frequency components. The magnitude of the imagery-induced aftereffects in Experiment 1 equaled the magnitude of the externally induced aftereffects obtained in Experiment 2 with the same subjects. By blurring the to-be-imaged patterns (Experiment 3), the fundamental Fourier components became the salient perceptual features of the stimuli, and the direction of the imagery-induced aftereffects was reversed from that of Experiment 1, indicating that the spatial frequency content of the imagery had changed from higher to lower frequencies. Under normal viewing conditions, subjects use the higher spatial frequencies associated with the perceptually salient edges of stimuli to construct their images. The results of Experiments 1 and 3 are discussed in light of a current controversy over the nature of information representation in imagery, and it is concluded that support has been obtained for the analog model of visual imagery.  相似文献   
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