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941.
Studies which have examined low tar and nicotine (LT/LN) cigarette smoking have failed, for the most part, to assess adequately the long-term effects of these cigarettes. Most studies have been short-term laboratory investigations of nicotine regulation. More practical strategies for changing to LT/LN cigarettes have largely been ignored. The present study examined long-term changes in smoking patterns following the gradual introduction of LT/LN cigarette smoking. Predicted increases in reported rates of consumption as well as carbon monoxide (CO) levels were not found for most smokers following changes to LT/LN cigarettes. Generally, smokers showed decreased rates of consumption, and a majority had lower CO levels at the end of treatment and during follow-up. Thus, LT/LN cigarette smoking would appear to be an alternative treatment goal for risk reduction in individuals who cannot stop smoking.  相似文献   
942.
Based on a review of reaction time studies, a model of mental arithmetic performance which emphasizes the process of fact retrieval from organized memory representations was proposed (M. H. Ashcraft, Developmental Review, 1982, 2, 213–236). In contrast to this view A. J. Baroody (Developmental Review, 1983, 3, 225–230) proposes that most mental arithmetic performance depends on procedural knowledge such as rules, heuristics, and principles. While Baroody's idea is both intriguing and potentially important, its exposition is quite vague and speculative. Without concrete suggestions as to the nature of the proposed rules and heuristics, especially for routine problems like 4 + 3 and 8 × 5, Baroody's proposal appears to be pertinent only to special cases like N + 0 and N + 1. Lacking this sort of elaboration, the alternative does not provide a useful or compelling explanation of the existing Chronometric results, and seems, at best, to be premature.  相似文献   
943.
Tested personality-environment congruence and differentiation, singly and in combination, as measured by the Vocational Preference Inventory (J. L. Holland, Palo Alto, California, Consulting Psychologists Press, 1977b), were predictive of reported job satisfaction for teachers employed in five subject matter areas. Time-related variables and sex were not significantly related to the job satisfaction measure used in the study.  相似文献   
944.
Pigeons were trained on a delayed discrimination task in which they were rewarded for pecking a white terminal stimulus (TS) presented 5 sec after a green initial stimulus (IS) and for not pecking the white TS when it followed a red IS. Each bird bridged the memory interval (MI) with overt mediational behaviors. Nevertheless, sustained retroactive interference (RI) effects were produced by houselight illumination (Experiments 1 and 3), and mild shock pulses (Experiment 5) but not white noise (Experiment 2) presented during the MI. Although the magnitude of the light-induced RI effect was proportional to the duration of houselight illumination (Experiment 4), the beginning-end effect described by W. A. Roberts and D. S. Grant (Journal of Experimental Psychology: Animal Behavior Processes, 1978, 4, 219–236) was not observed. These results not only attest to the between-task robustness of both light-induced RI and modality-specific effects with pigeons, but also support the hypothesis that RI effects result from the disruption of mediational activities possibly analogous to rehearsal. The results further demonstrate that an event interpolated within the MI need not be unexpected or novel to produce RI. Furthermore, the interpolated event can produce modality-specific RI effects even though it effects a different sense than do the IS and TS.  相似文献   
945.
The task of the neural organization of the native language, acquired by a direct method and of another language, studied at school, performed correspondingly by the left and the right hemispheres, was studied in the bilingual patient after unilateral electroconvulsive therapy used in psychiatry. It was established that in such a bilingual type the right hemisphere is concerned with the formation of deep semantic structures of the native language while the left hemisphere is responsible for the formation of second language deep structures and of surface structures of both languages. The effect of language learning method on cerebral organization of bilingualism is postulated.  相似文献   
946.
College student subjects performed a sequential typing task requiring bilaterally synchronized movements (Experiment 1) or unilaterally synchronized movements (Experiment 2) singly, and concurrently with silent and vocal rehearsal of verbal lists varying in redundancy. Rehearsal interfered with bilaterally synchronized movements more when the right hand was leading the sequence than when the left hand led, and with movements of the right more than the left hand in unilaterally synchronized movements. Results are interpreted in terms of intrahemispheric and general capacity competition between the concurrent performances.  相似文献   
947.
Children from a traditional school and two open schools were compared, using the Pictorial Self-Concept scale and the Attitude Toward School scale. To control for the self-selection of open school students, the traditional school subjects were divided into those whose parents favored and those whose parents did not favor open education. Three of the 12 analyses were significant, but not in the predicted, or in any orderly, direction. These results were attributed to chance. Attitude toward school was higher for females than males and decreased for kindergarden to grade 2. Self-concept increased form kindergarten to grade 2, with no significant sex differences.  相似文献   
948.
949.
Two kinds of explanations have been offered for the process by which three-term series problems are solved, one in terms of linguistic principles and the other in terms of visual-spatial imagery. Two experiments are reported in which three different classes of operations are brought to bear on the problem: (1) Manipulation of stimulus attributes (characteristics of problems), (2) manipulation of variables that selectively encourage or inhibit the use of imagery (facilitating instructions; the suppression of visualization by reading), and (3) measurement of relevant individual differences (spatial-reasoning ability). All of the results indicate that imagery plays a functional but not a necessary role in the solution of three-term series problems; it is suggested that imaginal representation is functional because it reduces the load on memory. An adequate explanation of problem-solving will have to address certain general issues, such as the diversity of forms of cognitive representation and differences within and between individuals in the choice of problem-solving strategies.  相似文献   
950.
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