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961.
Intermittent versus continuous visual control: a reply to Elliott   总被引:1,自引:0,他引:1  
Recently, Elliott (1986) has reported data that he claims are inconsistent with my hypothesis that a short-term motor memory system exists for guiding locomotion and other actions in space (Thomson, 1983). In fact, methodological flaws in Elliott's design make such conclusions unjustified and inappropriate. Moreover, insofar as comparisons can be made at all, the results are completely consistent with my own data.  相似文献   
962.
Much research on emotional facial expression employs posed expressions and expressive subjects. To test the generalizability of this research to more spontaneous expressions of both expressive and nonexpressive posers, subjects engaged in happy, sad, angry, and neutral imagery, and voluntarily posed happy, sad, and angry facial expressions while facial muscle activity (brow, cheek, and mouth regions) and autonomic activity (skin resistance and heart period) were recorded. Subjects were classified as expressive or nonexpressive on the basis of the intensity of their posed expressions. The posed and imagery-induced expressions were similar, but not identical. Brow activity present in the imagery-induced sad expressions was weak or absent in the posed ones. Both nonexpressive and expressive subjects demonstrated similar heart rate acceleration during emotional imagery and demonstrated similar posed and imagery-induced happy expressions, but nonexpressive subjects showed little facial activity during both their posed and imagery-induced sad and angry expressions. The implications of these findings are discussed.  相似文献   
963.
Recent research suggests that anxiety is not a single, unified reaction to perceived threat, but rather a cluster of interrelated factors whose relationships to performance change as the individual progresses from one test event to another. This study investigated the presumed linkages between traitlike predispositions to perceive threat and achievement performance, as mediated by statelike anxiety arousal on a longitudinal basis (Perceived Threat Anxiety Arousal Impaired Performance). College students were administered self-report questionnaire measures during a preenrollment period, after the first two midterms, and following the last two midterms in a general psychology course. Four performance measures and 26 motivational indicators were fitted to a 10-factor latent model using LISREL model-fitting techniques. Path-analytic interpretations of this structural model provided little evidence for the commonly held view that traitlike threat perceptions mediate performance via statelike anxiety reactions. Far more promising, theoretically, are those influences on test performance stemming from the self-attributional, cognitive domain. Overall, the findings support a recent reinterpretation of achievement anxiety as stemming from the disruptive effects of diminished ability perceptions (and hence, impaired personal worth), rather than from the interfering influence of diffused emotional arousalper se.  相似文献   
964.
The widely analyzed phenomenon of liberation theology needs to be discussed primarily at the theoretical level of its relation to political philosophy. Essentially, liberation theology serves as a means to co-opt the ideas, institutions, and motivations of religious people into the service of modern ideology, particularly Marxism. To fully comprehend this school of thought, one must understand it as an aspect of modern Gnosticism. That is, liberation theology accepts the reconstruction of human and cosmic purpose through an interpretation of classical religious ideas in the light of Marxist categories, themselves with direct and intelligible roots in political philosophy. Liberation theology proposes a this-wordly salvation as the content of the original revelation, while retaining all of the original religious terminology. The final test of such a proposal lies in its purpose and effect. The avowed justification of liberation theology, that is, the alleviation of the poor, can be best achieved by other means and ideas more in conformity with the tenets and means of classical religion and philosophy, which themselves cannot be reduced to mere politics.  相似文献   
965.
A home centred family therapy approach is described based on the McMaster model. This approach was applied in a controlled trial of three forms of intervention for mother and toddler problems. In this paper the experience of applying the approach is reported.  相似文献   
966.
The feeding and drinking behavior was examined in male rats with fornix transections and sham-operated control rats. Total food and water consumption was recorded but supplemented by a pattern analysis of feeding and drinking behavior. The behavior of the rats was continuously monitored during four hour morning and afternoon sessions under ad lib access and during a two hour session following adaptation to a restricted access feeding schedule. Rats with fornix transections were more active and exhibited increased frequencies of rearing, eating and drinking. The increased meal frequency in rats with fornix transections was accompanied by decreased meal durations and a reduction in the length of intermeal intervals. Total food and water consumption was unaffected by fornix transection as were the duration of sleep bouts and the frequencies of grooming, sleeping and carrying shavings. Fornix transections also reduced food carrying and food hoarding but only under conditions of restricted food access. The results suggest that fornix transection does not alter major homeostatic regulatory mechanisms nor does it alter the components of feeding and drinking behavior. Fornix transection alters, instead, the organization of microregulatory feeding and drinking patterns.  相似文献   
967.
Aged rats with extensive prior training on the radial maze retain the capacity for accurate spatial working memory (WM) for at least 3 months without practice. To investigate the temporal limits of this influence of prior experience we compared the reacquisition of spatial WM by a group of experienced 21.5-month-old rats to the original acquisition by naive 3-month-old rats. The aged rats had received 225 radial maze tests between 3 and 11 months of age. Despite 10 months without practice the old rats rapidly reacquired critical performance. Their reacquisition was markedly superior to original learning by the young rats, even when delays as long as 5 h were imposed between the rats' fourth and fifth choices during the daily tests in the eight-arm maze. Additional tests showed that neither young nor old rats employed a response strategy to maintain accurate spatial WM performance. Experience clearly confers long-lived protection against the otherwise deleterious effects of aging on spatial WM, but the mechanism by which this influence arises is unknown.  相似文献   
968.
Scopolamine effects on memory retention in mice: a model of dementia?   总被引:4,自引:0,他引:4  
Scopolamine-treated normal young human subjects exhibit memory dysfunctions analogous to those observed in demented patients. The dysfunctions are reversible by physostigmine but not by d-amphetamine which suggests that the memory impairment is specifically related to reduced cholinergic transmission caused by scopolamine. Scopolamine-induced amnesia has been proposed as a model for dementia where reduced cholinergic function is the suspected cause. We report seven experiments in young adult mice which examine scopolamine's effects on memory retention and whether its amnestic effects are specifically blocked by cholinergic agonists or cholinomimetics. Young adult mice were trained to avoid footshock in a T maze and their retention tested 1 week after training. Pretraining subcutaneous injection of scopolamine improved retention scores of "undertrained" mice at a dose of 0.01 mg/kg but impaired at a dose of 0.1 mg/kg. Post-training injection showed no effect at 0.01 mg/kg, enhanced retention scores at 0.1 mg/kg, and impaired at 1.0 mg/kg. The impairment by 1.0 mg/kg was blocked by injection 45 min post-training of each of two cholinergic drugs but was also counteracted by six drugs which act upon five other neural systems (catecholamine, serotonin, glycine, GABA, and hormonal). When scopolamine was injected 40 min pretraining, and each of eight drugs was injected immediately after training, the amnestic effect of scopolamine was only partially counteracted. This suggests that scopolamine impaired acquisition, in addition to some impairment of memory processing. This was confirmed by a direct study of acquisition rates of the avoidance response; 0.1 mg/kg of scopolamine impaired acquisition. The overall results indicate that pretraining administration of scopolamine impairs learning and to some degree memory processing. Counteracting scopolamine-induced amnesia, by either pretraining or post-training drug administration, is not specific to the cholinergic system.  相似文献   
969.
The authors examine and propose a synthesis of the theoretical tenets of ecumenical religious principles and cognitive-developmental stages of moral reasoning as a basis for value development. Because the college years represent a major opportunity for such value development, a case is made for formal programs and curriculum development for this period and an example is provided of coursework designed to promote systematic consciousness and the process of value growth.  相似文献   
970.
Food deprived, heterogeneous strain (HS/IBG) mice were trained on two different discrimination tasks for food reinforcement. In one experiment animals were trained to make spatial discriminations in a T maze. Immediately after training they were given subcutaneous injections of either substance P (1 ng/g) or vehicle. Twenty-four hours later the animals were given reversal training in the same maze. The results showed that substance P-treated animals took significantly longer to acquire the reversal habit than did control mice. In a second experiment, animals were trained to make visual discriminations in a T maze. Immediately after reaching acquisition criterion animals were injected with either substance P (1 ng/g) or vehicle. Different groups of mice were retrained on the same task either 1, 2, 3, or 7 days after original learning. Savings scores were calculated and, at every interval, substance P-treated mice retained the task better than control animals. One interpretation of these data is that substance P-treated mice remembered the original task significantly better than vehicle-injected control animals.  相似文献   
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