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991.
Substitution and caloric regulation in a closed economy.   总被引:1,自引:1,他引:0       下载免费PDF全文
Three experiments were conducted to study the effect of an imperfect substitute for food on demand for food in a closed economy. In Experiments 1 and 2, rats pressed a lever for their entire daily food ration, and a fixed ratio of presses was required for each food pellet. In both experiments, the fixed ratio was held constant during a daily session but was increased between sessions. The fixed ratio was increased over a series of daily sessions once in the absence of concurrently available sucrose and again when sucrose pellets were freely available. For both series, increases in the fixed ratio reduced food intake, but body weight was reduced only in the no-sucrose condition. In the sucrose condition, body weight and total caloric intake (sucrose plus food) were relatively unaffected by increases in the fixed ratio. At all fixed ratios, food intake was proportionally reduced by the intake of sucrose. In Experiment 3, monkeys obtained food or saccharin by pressing keys; the fixed ratio of presses per food pellet was increased once when tap water was each monkey's only source of fluid, again when each monkey's water was sweetened with saccharin, and a third time when each monkey had concurrent access to the saccharin solution and plain water. Increases in the fixed ratio, but not the intake of the saccharin solution, reduced each monkey's food intake. Because neither rats' sucrose nor monkeys' saccharin intakes affected the slope of the respective demand curves for food, monkeys and rats increased their daily output of presses and thereby defended their daily intake of those complementary elements of food. However, sucrose reduced rats' food intake. The relative constancy of body weight and total caloric intake in the sucrose condition is consistent with the possibility that rats tended to regulate caloric intake.  相似文献   
992.
Conclusion The deeper meaning of education, says Dewey in his Human Nature and Conduct (1922), which distinguishes the justly honored profession from that of mere trainer, is that a future new society of changed purposes and desires may be created by a deliberately humane treatment of the impulses of youth (p. 69). For Dewey, a truly humane education consists in an intelligent direction of native activities in the light of the possibilities and necessities of the social situation (p. 70). Student impulse and interest are not to be suppressed nor continually vented in unrestrained expression. In view of the plasticity of youth, there is little danger that allowing the role of student interest will lead away from important objectives of the curriculum.Education which respects the integrity of the student is a prerequisite of the kind of educated public suited for fuller participation in the democratic processes which properly direct and reconstruct our social life. The citizen appropriate for a democratic society is neither the dull conformist nor the superficial, gushing, non-conformist or sensualist. Individual impulse and initiative is neither to be damned up nor frivolously expressed. Meaningful participation and fuller social reconstruction require that we respect the social conditions for the possibility of knowledge and its growth, and this is more easily achieved, and more broadly appealing, when we speak of plans for the school environment. Respect for the cognitive and developmental needs of our own children and young people is fundamental to the self-respect of any viable society. Education could be philosophical praxis for a better world.  相似文献   
993.
Four experiments used a conditioned taste aversion procedure to examine the potential for CS-alone extinction treatment to produce a conditioned stimulus that possesses inhibitory properties. In Experiment 1, saccharin was paired with LiCl, and then saccharin was presented alone for several trials to produce extensive behavioral extinction. Animals receiving this treatment were retarded in reacquiring conditioned responding to saccharin relative to control subjects receiving conditioning to the flavor for the first time. In Experiment 2, the extinguished saccharin stimulus was shown to decrease conditioned responding to a known excitor when the two stimuli were presented in compound as a summation test. Experiments 3A and 3B replicated the findings of Experiments 1 and 2 while providing evidence that the effects were not due to the differential effects of neophobia during testing. These three experiments revealed that an extinguished conditioned excitor passes retardation and summation tests for conditioned inhibition. Experiment 4 found that extinction of a known excitor was slowed when the excitor was extinguished in compound with a previously extinguished conditioned stimulus. That is, an extinguished CS provided protection from extinction to another CS, a finding also consistent with the view that extinction produces conditioned inhibition.  相似文献   
994.
995.
The repetition blindness effect (RB) occurs when individuals are unable to recall a repeated word relative to a nonrepeated word in a sentence or string of words presented in a rapid serial visual presentation task. This effect was explored across languages (English and Spanish) in an attempt to provide evidence for RB at a conceptual level using noncognate translation equivalents (e.g.,nephew-sobrino). In the first experiment, RB was found when a word was repeated in an English sentence but not when the two repetitions were in different languages. In the second experiment, RB was found for identical repetitions in Spanish and in English using word lists. However, the crosslanguage condition produced significant facilitation in recall, suggesting that although conceptual processing had taken place, semantic overlap was not sufficient to produce RB. The results confirm Kanwisher’s (1987) token individuation hypothesis in the case of translation equivalents.  相似文献   
996.
Developmental stuttering (DS) may be related to the extrapyramidal motor system and shares many clinical similarities with Tourette's syndrome (TS), which is widely believed to be associated with extrapyramidal dysfunction. Twenty-two stutterers were examined for neuropsychiatric features commonly seen in TS, including tics, obsessive-compulsive behaviors (OCB), and attention deficit disorders. Eleven stutterers displayed motor tics, and symptoms of OCB were observed at rates similar to those seen in persons with TS. Few stutterers demonstrated significant attentional deficits. Findings are consistent with models suggesting extrapyramidal involvement in DS and raise the possibility that DS and TS are pathogenetically related.  相似文献   
997.
Mothers of problem and nonproblem toddlers rated videotapes of their own and unfamiliar children's behavior. They classified the behaviors as positive, negative, or neutral, and evaluated the intensity of the positive or negative behaviors. Ratings did not differ by problem status; however, all mothers classified their own children's behavior as less negative than did an independent observer. Mothers also evaluated all children's negative behavior as less aversive than did the observer. Finally, mothers mistakenly classified less of their own children's behavior as negative and more as positive when compared to their biases in classifying unfamiliar children's behavior.  相似文献   
998.
This study examined the effect of parental distress on mothers' and fathers' reports of children's emotional and behavioral problems. The subjects were the parents of 696 children aged 10 to 11 or 14 to 15 years living in two-parent families in the community. The study utilized an extended version of the model previously employed by Fergusson, Lynskey, and Horwood (1993) to examine the impact of maternal depression on mothers' reports of children's behavior. In the present study, the extended model was used to assess the impact of distress on reports of childhood externalizing and internalizing problems obtained from both mothers and fathers. The results suggested that distress had little influence on mothers' or fathers' reports of childhood behavior problems. It is concluded that in community studies the size of any bias in mothers' and fathers' reports of childhood behavior problems due to parental distress is likely to be very small and of little clinical significance.  相似文献   
999.
Anti-foundationalism is a central topic in recent legal scholarship. The critical legal studies movement (CLS) has mounted a strong challenge to the traditional belief that legal materials (constitutions, statutes, and precedents) determine legal outcomes and constrain judicial decision making. This scholarship has overlooked, however, the degree to which the debate between traditional legal determinacy and anti-foundational indeterminacy is yet another manifestation of a continuous debate in Western thought – one that has its roots in pre-Socratic rhetoric and philosophy.This paper traces the indeterminacy thesis back to the contest of ideas between Protagoras and Plato. I examine two well-known and elated Protagorean notions: first, that two arguments (logoi) are always set in opposition to one another with regard to every matter and, second, that the rhetorician can always make the weaker argument the stronger. I contend that taking these Protagorean notions seriously – perhaps even more seriously than self-avowed anti-foundationalists customarily do – leads paradoxically to a modified endorsement of foundationalism that is nevertheless wholly consistent with the Protagorean project. Calling upon texts by Aristotle, Seneca and René Girard, I focus upon how fictionality in representations of Platonically conceived Truth reveals a binarization in thought that is simultaneously untenable and unavoidable.  相似文献   
1000.
This study investigated the relationship between acquisition of psychoeducational principles and symptomatic improvement in depressed in-patients. One hundred and twenty-three inpatients hospitalized on a Cognitive Therapy Unit were administered the Test of Cognitive Behavioral Principles (TCBP) and the Beck Depression Inventory at admission and discharge. It was predicted that the TCBP scores would be higher at discharge than at pre-testing at admission. Further, it was hypothesized that the higher TCBP scores at post-test would be significantly correlated with lower Beck Depression Inventory scores at post-test. The results revealed that inpatients' TCBP scores improved over the course of treatment supporting the first hypothesis. However, the data did not support the second hypothesis as there was not a significant relationship between the TCBP scores and the BDI scores at discharge. The results are discussed in terms of clinical, theoretical, and methodological implications.  相似文献   
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