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41.
Effects of deprivation upon counting and timing in rats   总被引:3,自引:3,他引:0       下载免费PDF全文
Two procedures were used in an investigation of the effects of deprivation upon counting and timing. Under the first procedure, fixed minimum interval (FMI), the rat received liquid reinforcement every time it pressed bar B after having waited a minimum of 5 sec following a press on bar A. Under the second procedure, fixed consecutive number (FCN), reinforcement was delivered every time the rat pressed bar B following a run of at least four consecutive responses on bar A.

Water deprivation was varied over a set of values ranging from 4 to 56 hr. Deprivation had almost no effect on the waiting time in the FMI procedure, or on the number of responses per run in the FCN procedure. With both procedures, increasing deprivation shortened the pause between reinforcement and the next response. In the FCN procedure, the speed with which the runs were executed increased with increasing deprivation, although the number of responses in these runs was relatively unaffected.

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Dependency and brain damage in alcoholics   总被引:1,自引:0,他引:1  
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The essay examines the argument advanced by E.D. Hirsch, Jr., for instituting ‘cultural literacy’ as a fundamental priority of schools. A number of confusions and equivocations in Hirsch's reasoning are identified, and the propensity of his project to indoctrinate is exposed. Among the features of Hirsch's argument shown to be troubling are his shifting construal of ‘language’, his inconsistency about the requirements of cultural literacy, and his uncritical relation to traditional images of the American past and present. The upshot is to raise the question why Hirsch's project has elicited wide support and praise.  相似文献   
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Sex differences in visual-spatial ability: The role of performance factors   总被引:4,自引:0,他引:4  
Two studies were designed to explore the role of performance factors as sources of the frequently noted higher male scores on visual-spatial ability tests. In the first study, the mental rotations test (MRT) was administered to male and female college students of equally high quantitative ability (based on SAT math scores). Although males had significantly more correct responses on the test than did females, their advantage was eliminated when the ratio of correct responses to items attempted was used as the dependent measure. In the second study, the same test was administered to new groups of male and female college students. In this sample, the males had significantly higher SAT math scores. The MRT was administered under standard, timed conditions and under untimed conditions. Both raw and ratio scores were calculated. With SAT math score as the covariate, analyses of covariance indicated that males demonstrated higher performance in the timed, raw-score condition but not in the untimed or in the ratio-score conditions. The theoretical and social policy implications of these studies are discussed.  相似文献   
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The current literature suggests that individuals who chronically abuse alcohol exhibit a wide variety of cognitive deficits resulting from cerebral dysfunction that is either directly or indirectly related to their alcohol consumption history. Cognitive deficits have been hypothesized as having implications for standard alcohol treatment efficacy as they may directly affect cognitively impaired individuals’ abilities to utilize various treatment modalities. Although evidence is accumulating that suggests this is actually the case, the majority of alcohol treatment programs neither directly consider the impact cognitive deficits have on treatment efficacy nor do they employ cognitive rehabilitation treatment strategies to remediate identified cognitive deficits. Few studies exist that investigate the remediability of neurobehavioral deficits or the efficacy of integrating cognitive rehabilitation strategies into more traditional treatment programs. Empirical investigations conducted to date indicate that some cognitive deficiencies secondary to alcoholism are amenable to cognitive rehabilitation and this remediation is generalizable. Rigorous well-controlled treatment outcome investigations are needed in order to determine the efficacy of cognitive rehabilitation techniques in naturalistic settings using ecological outcome measures. Also, emphasis should be placed on integrating cognitive rehabilitation techniques with proven efficacy into traditional alcoholism treatment programs.  相似文献   
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How can we explain that an assertion on something perceived can be understood in the same manner by somebody who cannot perceive that scene? This problem bases the interest in computational linguistics in how listener modeling could possibly be harmonized with reference semantics. Mental images substituting real perception appear as a way out. The architecture of the listener model has to be adapted to the creation and use of such pictorial data structures. Furthermore, the relation between the latter and a verbal (i. e., propositional) representation must be understood. The resulting architecture of a listener model with reference semantics can be employed to solve communicational problems from three general classes in a better way, as is demonstrated by an example implementation.  相似文献   
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The results of empirical research in psychology and psychiatry are increasingly being used to formulate as well as understand problems at the interface of law and psychiatry. There has been a proliferation of studies, such as the determinants of individual competence or threat to self or others, the results of which are influencing policy and legislative decisions as well as buttressing holdings in court cases. In this article, I explore the issues of interpretation of epidemiological studies, particularly the role of ideological positions on the design and results of empirical findings, the importance of the way data are interpreted, and the role of ideologies in the way research findings are presented to provide support for policy positions. Two levels of analysis are involved in determining the validity of a study. The first addresses the questions of whether the study meets the statistical and epidemiological requirements for reliable results. These include considerations such as the appropriateness of the study design and methods for gathering and interpreting data. The second focuses on the underlying framework of the study. This involves factors such as the perspectives and values of those conducting the study, the explicit and implicit dominating ideologies where they operate, and the extent to which the study is constructed to reaffirm specific ideologies. This level of analysis is essential for disclosing the influences of ideologies on the results of studies and the way in which data are interpreted. In this article, I try to demonstrate through critiques of selected studies that the first stage of analysis is insufficient without an examination of underlying preconceived values to establish the meaningfulness of results.  相似文献   
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