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141.
Context and structure in conceptual combination   总被引:8,自引:0,他引:8  
  相似文献   
142.
143.
Two modes of learning for interactive tasks   总被引:5,自引:0,他引:5  
N A Hayes  D E Broadbent 《Cognition》1988,28(3):249-276
  相似文献   
144.
A longitudinal design was employed to test the main and stress-moderating effects of young adolescents' perceived family environment (Family Environment Scales; FES; Moos & Moos, 1981) on their depression, anxiety, and self-esteem. This study was part of a larger longitudinal project (L. Cohen, Burt, & Bjorck, 1987) that demonstrated the significant cross-sectional effects of the young adolescents' controllable and uncontrollable negative events, and the significant longitudinal effects of the former. The present cross-sectional analyses demonstrated the hypothesized main effects of the FES scores; families perceived as cohesive, organized, and expressive were related to positive psychological functioning, whereas families perceived as conflict-ridden and controlling were related to negative functioning. However, in general these effects were nonsignificant in the longitudinal analyses. Although there were a number of significant Negative Events x FES interactions, in no instance did the pattern support the hypothesized stress-buffering role of positive family climate.  相似文献   
145.
146.
In recent years in research on intergroup relationships, the assumption has increasingly been made that discrimination dominates decisions when individuals allocate resources between (members of) own and other group. Conversely, in empirical studies of interpersonal decision-making, including an extensive literature on the development of children's allocation rules within dyadic relationships, it has been repeatedly observed that in dyadic relationships choices though responsive to various changes in the environment, are more strongly governed by fairness rules. The present research extends the interpersonal fairness paradigm to the intergroup case, and examines the effects of some of those variables, namely, children's age, input and attitudes toward other, that have been observed to influence choice behaviour within interpersonal relationships. The findings indicate that as children are socialized, fairness rules also play an increasing dominant role in intergroup allocation decisions, and that both relative input and the language of the outgroup influence such decisions. At the same time, there is some preliminary evidence to indicate that the relative strength of self-interest may be somewhat stronger in intergroup than in interpersonal relationships. Finally, a number of the issues that must be confronted in comparing the two more important forms of human social choices, interpersonal and intergroup decision-making, are considered.  相似文献   
147.
The relationship between anxiety and depression was examined in a sample of 106 children and adolescents referred to an outpatient anxiety disorder clinic for children. Twenty-eight percent of patients with DSM-III diagnoses of anxiety disorders displayed a concurrent major depression. Children with anxiety disorders plus major depression were found (1) to be older, (2) to demonstrate more severe anxiety symptomatology, and (3) to be diagnosed with different rates of certain anxiety-disorder subtypes, when compared to anxious patients without major depression. Nondepressed anxious children and adolescents did not differ from a psychopathological control group in severity of either anxiety or depression symptoms.  相似文献   
148.
Force variability in isometric responses   总被引:2,自引:0,他引:2  
In the present study we examined the contribution of different impulse parameters to peak force variability in an isometric task. Five experiments are reported that each held constant a different impulse parameter while allowing the other impulse parameters to vary. The results indicate that change in force level is the parameter that has the greatest effect on peak force variability, although time to peak force and preload also systematically influence response variability. A formula that accommodates the relation between impulse parameters and force variability is proposed. The data suggest that even in isometric tasks, it is the force-time properties of the impulse, rather than discrete parameters such as peak force, that determine the outcome variability.  相似文献   
149.
Wistar rats of three age groups were tested in an automated tunnel-maze system of variable geometry to investigate whether changes in spontaneous locomotor activity and in learning and memory develop differentially or in a correlated fashion as a function of age. Senescent (30 months) as well as mature-adult (17 months) rats showed an age-correlated decline of locomotor activity as compared to the mature-young (5 months) group. Both working-memory (measured as within-trial arm discrimination performance) and reference-memory (measured as avoidance of "blind alley" visits) were severely affected in the senescent group, whereas the middle-aged animals suffered only from a working-memory deficit. The findings provide evidence that locomotor deficits do not necessarily interfere in the assessment of age-related changes in cognitive performance. Furthermore the results support the hypothesis that working and reference memory have different underlying physiological correlates and that these neuronal systems are differentially affected by the aging process.  相似文献   
150.
Serotonergic and opiate interactions in the modulation of drug- and environmental-induced analgesia were assessed in 6-day-old Sprague-Dawley-derived rat pups using tail-flick testing procedures. In these experiments the serotonergic antagonist metergoline was observed to attenuate both the analgesia induced by the opiate agonist morphine and the analgesia induced by isolation from siblings and the dam, an environmental manipulation which has previously been shown to be associated with increases in opiate activity. In contrast, the opiate antagonist naloxone was observed to be ineffective in blocking not only analgesia induced by the serotonergic agonist quipazine, but also analgesia induced by long-term deprivation from the dam and food, a manipulation that has been previously reported to induce increases in serotonergic utilization. These results suggest that in the neonate, as in the adult, the serotonergic modulation of nociception appears to occur "downstream" from the opiate systems serving to regulate nociception following both drug- and environmental-induced alterations in pain sensitivity. Analgesia induced by long-term deprivation from food and the dam appears to be strongly related to increases in serotonergic activity and relatively unaffected by opiate antagonism, whereas analgesia induced by isolation from siblings and the dam may be related to increases in opiate activity, but modulated by serotonergic systems serving to regulate pain responsivity. Thus alterations in the environment, mediated at least in part by alterations in opiate and serotonergic activity, appear to play an important role in influencing the sensitivity of the neonate to pain stimuli.  相似文献   
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