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181.
In pigeons performing under a multiple schedule of food presentation, low key-pecking rates (0.18 to 0.29 responses per second) were maintained during 3-min fixed-interval components by requiring a 4-, 5-, or 6-sec pause preceding the food-delivery response (tandem DRL), while higher rates (0.70 to 1.37 responses per second) were maintained in alternative fixed-interval components by requiring a pause of no more than 40 msec preceding the food-delivery response (tandem DRH). Thus, reinforcement density was equal but overall response rates markedly different in the two schedule components. Pentobarbital (3, 10 mg/kg) had effects on overall rates of responding consistent with a rate-dependency interpretation (low rates were increased while higher rates were decreased), but d-amphetamine (0.03 to 3 mg/kg) either failed to increase low overall rates in the tandem DRL components or increased them only slightly. Effects of both drugs on local responding within the fixed-intervals were always related in an orderly way to control response rate, but the extent of rate increases produced by d-amphetamine was modifed in some birds by pause requirements such that the drug increased comparable rates less when these occurred in the tandem DRL component than when they occurred in the tandem DRH components. Control rate is an important determinant of drug effects, independent DRH components. Control rate is an important determinant of drug effects, independent of reinforcement density maintaining rates, and independent of environmental influences, such as response-spacing requirements for food presentation, that can modify the extent of some drug-produced rate changes.  相似文献   
182.
The goal of this study was to estimate the prevalence and correlates of illicit drug use (IDU) among university students from eight countries in Africa and three countries in the Caribbean. In a cross-sectional survey, data were collected from 7 017 undergraduate university students (mean age 21.1, SD = 2.7, age range of 18–30 years) from 11 countries. Overall, 17.2% and 3.5% reported infrequent (1–9 times) and frequent (10 or more times) IDU in the past 12 months. In multivariate logistic regression models, residing on or off campus on their own, living in an upper middle or high income country, current tobacco use, binge drinking, and having been in a physical fight in the past 12 months were associated with both frequent and infrequent IDU. In addition, higher intrinsic religiosity and older age was found to be protective from infrequent IDU and associated with never using illicit drugs. The influences on IDU identified may be utilised for the design and implementation of social intervention programmes to curtail IDU by college students.  相似文献   
183.
ObjectiveTo explore the effect of aerobic exercise on working memory according to exercise intensity in patients with methamphetamine (MA) dependence.DesignTwelve-week randomized controlled trial.MethodForty-five MA-dependent patients were divided randomly into three groups participating in 12-week moderate- and high-intensity aerobic exercise interventions and no intervention (control), respectively. Working memory performance was assessed using a 2-back task, and a combined functional near-infrared spectral imaging–event-related potential measure was used to identify spatial and temporal components of the neurofunctional underpinnings of this performance.ResultsHigh-intensity exercise significantly enhanced the discernment aspect of working memory. It also decreased N1 and P2 amplitudes, and increased neural activity in the left dorsolateral prefrontal cortex.ConclusionsThe findings of this study suggest that high-intensity aerobic exercise can enhance working memory and neural activity in MA-dependent patients, and thus that it may serve as an effective therapeutic tool for these patients.  相似文献   
184.
From IF to BI     
We take a fresh look at the logics of informational dependence and independence of Hintikka and Sandu and Väänänen, and their compositional semantics due to Hodges. We show how Hodges’ semantics can be seen as a special case of a general construction, which provides a context for a useful completeness theorem with respect to a wider class of models. We shed some new light on each aspect of the logic. We show that the natural propositional logic carried by the semantics is the logic of Bunched Implications due to Pym and O’Hearn, which combines intuitionistic and multiplicative connectives. This introduces several new connectives not previously considered in logics of informational dependence, but which we show play a very natural rôle, most notably intuitionistic implication. As regards the quantifiers, we show that their interpretation in the Hodges semantics is forced, in that they are the image under the general construction of the usual Tarski semantics; this implies that they are adjoints to substitution, and hence uniquely determined. As for the dependence predicate, we show that this is definable from a simpler predicate, of constancy or dependence on nothing. This makes essential use of the intuitionistic implication. The Armstrong axioms for functional dependence are then recovered as a standard set of axioms for intuitionistic implication. We also prove a full abstraction result in the style of Hodges, in which the intuitionistic implication plays a very natural rôle.  相似文献   
185.
温尼科特是英国精神分析客体关系学派的重要代表人物,提出了独特的精神分析治疗观,以提供抱持性的分析情境为核心,强调退行至依赖的治疗过程,重视精神分析师的反移情中的恨的情绪体验,珍视病人的主动不交流等,在很多方面颠覆了经典的精神分析治疗观。  相似文献   
186.
Regulating the Risks of Closeness   总被引:1,自引:0,他引:1  
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187.
This study examined the point prevalence of smoking in patients with anxiety disorders who do not have comorbid alcohol or substance abuse or dependence (ASAD). In a retrospective chart review, the smoking status of 581 patients with anxiety disorders was assessed. Patients, ages 18–65, were seeking treatment for anxiety disorders at an outpatient clinic that specialized in anxiety and related disorders. All participants were interviewed using the Anxiety Disorders Interview Schedule—IV, during which their smoking status was assessed. The prevalence of smoking across all anxiety disorders was 14.8%, which is much lower than found in the general population (23.3%; CDC, 2002) and even lower than previous estimates in individuals with comorbid anxiety and ASAD. Individuals with panic disorder and generalized anxiety disorder had the highest prevalence of smoking, although these rates were still considerably lower than those found in previous studies of smokers with anxiety disorders. Reasons for lower prevalence estimates are discussed.  相似文献   
188.
药物成瘾是指持续使用成瘾药物, 出现耐受性和戒断症状并严重阻碍正常社会功能的精神疾病。工作记忆在调节药物成瘾行为中扮演了中心角色:在神经易感性和易感人格特质基础上, 低工作记忆容量导致危险决策和去抑制性, 进而影响寻求药物和复吸行为。目前的研究基于已经产生成瘾的个体, 无法区别神经易感性、人格特质以及工作记忆缺陷是药物成瘾的原因还是结果; 而且, 仅从认知角度研究药物成瘾的原因, 会忽视该行为受多个因素影响的事实。  相似文献   
189.
Nicotine dependence has been found to be a significant factor in adolescent smoking persistence. However, measures of this construct are primarily adult-derived, limiting their utility as bases for characterizing nicotine dependence and formulating youth intervention strategies. This issue is of particular importance among substance abusing youth who have substantially higher rates of cigarette smoking than do adolescents in the general population. The objectives of this preliminary study were to examine the construct validity of the DSM-IV nicotine dependence criteria and the modified Fagerström Tolerance Questionnaire (mFTQ) and to compare the DSM-IV diagnostic criteria for nicotine dependence with the mFTQ in a sample of 67 adolescent smokers in treatment for substance abuse. Results revealed that more participants were classified as nicotine dependent using DSM-IV criteria than by mFTQ scores. Little evidence was found for construct validity of these measures and convergence between the two measures was low. Findings also suggested that the present measures do not capture optimally broad dimensions of adolescent nicotine dependence.  相似文献   
190.
采用熟悉词和不熟悉词为干扰材料,考察了干扰材料的熟悉性对语篇阅读的影响.实验第一阶段要求不同认知方式被试朗读插入熟悉度不同干扰材料的短文,考查被试的阅读效率;第二阶段采用学习—自由回忆任务考查不同提示条件下在短文中使用过的干扰词和新词的学习效果.结果发现:(1)对场独立者而言,熟悉词的干扰作用明显大于不熟悉词,而对场依存者而言,熟悉词和不熟悉词的干扰作用无差异;(2)在提示条件下,被试对干扰词的回忆量大于对新词的回忆量.研究结果表明,在语篇阅读过程中,与场依存者相比,熟悉的干扰材料对场独立者的影响更大;熟悉词比不熟悉词产生更大干扰的原因可能是由于其激活了读者更多的经验,而非具有加工的优势.  相似文献   
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