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331.
A “strong” mathematical model for the relation between observed scores and true scores is developed. This model can be used
  1. 1.
    To estimate the frequency distribution of observed scores that will result when a given test is lengthened.  相似文献   
332.
Postictal sexual drive levels induced by limbic discharges were studied in eight adult male cats. Although sexual drive was exclusively dependent upon the presence or absence of testosterone, the level or degree of drive was dependent on the relative amounts of circulating testosterone and catecholamines in addition to the bioelectric state of the testosterone-binding cells. The limbic discharge was thought to induce postictal hypersexuality by its propagated discharge, suppressing the association neocortex and simultaneously activating the sexual hormone-binding cells of the diencephalon. The dissociation of the neocortex from the diencephalon was considered as a functional postictal diaschisis. These postictal physiologic changes were thought to account for the irrational automatic behavior and memory loss characteristic of patients with psychomotor seizures.  相似文献   
333.
Dextrorphan is a noncompetitive blocker of N-methyl-D-aspartate (NMDA) receptors. Since NMDA blockers are known to reduce the locomotor stimulatory and toxic effects of cocaine, it was speculated that dextrorphan would attenuate cocaine-induced behavioral excitatory motor activity associated with and without mechanical perturbation of the brainstem. Technique: Motor activity was recorded following dextrorphan and/or cocaine challenge in 25 SHR rats. Ten were naive subjects. Mini-osmotic pumps delivering cocaine (2.5 mg/0.49 ul/hr) were placed in 15 subjects, and infusion was halted after the third infusion day. On the fifth day either a dextrorphan (25 mg/kg, subcutaneous) or a dextrorphan and cocaine (40 mg/kg, intraperitoneal) challenge was done. Ten rats had bipolar electrode implants in the bilateral brainstem. Five were treated with DC current lesions in each of 12 days over a 3-week period. The effects of brainstem lesions on escape behavior were also evaluated in those five subjects. Results: In the naive subjects, dextrorphan reduced motor activity (P=.0001), whereas combined cocaine and dextrorphan increased motor activity (P=0.04). In lesioned subjects, dextrorphan decreased motor activity (P=0.0001). In electrode implant subjects, combined dextrorphan and cocaine challenge decreased the motor activity (P=0.04). Hyperactivity in the electrode implant group was greater than in the lesioned subjects. Midbrain electrolytic lesions attenuated escape behavior. A variety of behaviors were produced by brainstem lesions. Conclusions: Dextrorphan and brainstem lesions reduced motor hyperactivity and escape behavior. In electrode implant subjects dextrorphan counteracted the expected cocaine excitatory motor effects. Dextrorphan did not activate nor facilitate seizures.  相似文献   
334.
335.
Moving from Cognition to Action: A Control Theory Perspective   总被引:2,自引:0,他引:2  
  相似文献   
336.
337.
Some of the ways in which the occupational and educational aspirations and expectations of 13-year-olds are influenced by local opportunity structures are examined. The educational and occupational aspirations of 13-year-olds in contrasting local labour markets are explored, along with the ways in which their plans may be affected by living in an area with restricted opportunities. It is argued that differences in aspirations and expectations are largely explained by the socio-economic location of families rather than by the structure of the local labour market. However, 13-year-olds have an awareness of the limited nature of local job opportunities, and many realise that migration may be necessary if they are to fulfil their aspirations.  相似文献   
338.
Theories of social categorization were used to generate hypotheses concerning the impact of drug involvement on the attitudes and knowledge structures that people use in making drug-related judgments. Data indicated that greater drug exposure tended to foster more complex knowledge structures for drugs and drug users as revealed by subjects’ perceptions of drug users, tolerance for drug use, and perceptions of drug seriousness. Basically, high drug involvement in terms of personal alcohol use and associating with illicit drug users was related to greater individuation of drug user types. Therefore, high-involved subjects, relative to low-involved individuals, were better able to discriminate between different drug user subtypes and drug user subtypes were more important to high-involved subjects when responding to drug-related survey items.  相似文献   
339.
It is common to assume that the proportion of correct answers to an item has a normal-ogive or logistic relationship to total test score. However, this is shown to be a mistaken and an undesirable notion.  相似文献   
340.
Guttman's principal components for the weighting system are the item scoring weights that maximize the generalized Kuder-Richardson reliability coefficient. The principal component for any item is effectively the same as the factor loading of the item divided by the item standard deviation, the factor loadings being obtained from an ordinary factor analysis of the item intercorrelation matrix.  相似文献   
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