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241.
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Previous work from our laboratory showed that intermittently re-exposing rats to reinforcement for lever pressing in a training (A) context, while eliminating lever pressing in a second (B) context, increased ABA renewal of lever pressing relative to rats that experienced only Context B during response elimination. In the current study, we replicated these procedures while assessing renewal in the presence of a novel context (i.e., ABC renewal). Unlike the findings described above, renewal was reduced in the group that experienced re-exposure to Context A during lever-press elimination relative to rats that experienced only Context B. These findings suggest that alternating between contexts associated with reinforcement and extinction during treatment reduces the probability that organisms will respond in novel contexts. These outcomes may be the result of discrimination and/or generalization processes. Moreover, this training procedure may offer a potential mitigation strategy for ABC renewal.  相似文献   
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„Ethnoscience”︁ in the early 1960s provides a prototypical case of an elite specialty. With easy access to recognition, there was only a loose confederation, not at all the kind of tightly knit social network with a garrison worldview typifying revolutionary groups. Elite specialities both grow and dissolve more rapidly than revolutionary groups; they require less commitment, and concomitantly offer less resistance to competitors. Ethnoscience lacked a single leader and was never monolithic.  相似文献   
245.
Diazepam-induced impairment of a go-no go successive discrimination   总被引:1,自引:0,他引:1  
Diazepam (2.0 and 4.0 mg/kg, but not 1.0 mg/kg) administered in eight acquisition sessions significantly impaired the light-cued successive discrimination of male Sprague-Dawley rats. In two postdrug (vehicle) sessions, groups previously treated with the drug demonstrated good recovery in discrimination. An analysis of response components indicated that the impairment was due to the failure of drugged subjects to inhibit or withhold responses during the no go periods of the task. These findings are consistent with a "disinhibitory hypothesis" of drug impairment. The similarity of the present findings to those previously reported with chlordiazepoxide suggests that such effects are a generalized characteristic of the benzodiazepine class of drugs.  相似文献   
246.
Sex Roles - Although children start to adopt gender stereotypes by the age of three, there is less evidence about how early they start to sanction other children’s counter-stereotypical...  相似文献   
247.
Continental Philosophy Review - Violence is essential to religion, while religion holds the promise of transcending violence. The designation religious refers not to a type of violence, but to a...  相似文献   
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The main purpose of this study was to analyze the structure and content of real-life attributions, using these data to examine some important theoretical and empirical issues in attribution theory. The causal attributions examined came from free-response verbal protocols of explanations for marital separation of 29 males and 33 females living in New Zealand. Respondents gave causal importance weghts to the attributions from their verbal protocols, utilizing the technique of subjective magnitude estimation. Ipsative data, representing perceived causal responsibility for different attribution targets (self, ex-spouse, external factors, etc.), were derived from these weights, and the impact a range of independent variables exerted on these derived free-response attribution percentages was examined. Evidence is presented which supports the validity and reliability of this technique. The normative data gathered was found to be both consistent and inconsistent with different aspects of attribution theory. The implications for attribution theory are discussed.  相似文献   
250.
Data from experimental animals suggest that 5-hydroxytryptamine (5HT) may have an inhibitory effect on aggression, while clinical studies have found a correlation between pathological aggression and low brain 5HT. To investigate this relationship further we used amino acid mixtures designed to raise or lower the levels of the 5HT precursor, tryptophan. Normal male subjects were given tryptophan-depleted, balanced, or tryptophan-supplemented ammo acid mixtures and tested for aggression 5 hours later. The balanced amino acid mixture served as a control for the tryptophan depletion and supplementation. Testing for aggression was done using the Buss paradigm in which subjects deliver electric shocks to a (nonexistent) partner in response to stimulus tones. Duration and intensity of shock delivered were the measures of aggression, while responsivity to the stimulus tones was the measure of perceptual sensitivity. Neither tryptophan supplementation nor tryptophan depletion had any effect on these measures of aggression or perceptual sensitivity. We conclude that raising or lowering the synthesis of brain 5HT through alterations in tryptophan availability does not influence aggression in normal males as measured by the Buss task.  相似文献   
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