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91.
采用改进的点–探测范式,考察熟练双语者在情绪注意偏向中对情绪信息加工的优势效应及该效应产生的原因。采用2(熟练双语者和非熟练双语者)×3(靶刺激与消极词汇出现的位置一致、不一致和中性条件)×2(线索呈现时间为100 ms和400 ms)的混合实验设计,记录被试对靶子的按键反应时和错误率。结果发现:线索呈现100 ms和400 ms时,两组被试在注意定向分数上无显著差异;线索呈现100 ms时,两组被试的注意解除分数无显著差异;线索呈现400 ms时,熟练双语者的注意解除分数显著小于非熟练双语者。结果表明,在情绪注意偏向任务中,熟练双语者比非熟练双语者表现出了对情绪词汇信息更好的注意抑制控制能力,体现出对情绪信息加工的双语优势效应,产生这一优势效应的原因是熟练双语者在注意的晚期阶段比非熟练双语者具有更好的情绪信息注意解除能力。  相似文献   
92.
Pigeons were trained to discriminate 5 mg/kg pentobarbital from saline under concurrent variable-ratio (VR) VR schedules, in which responses on the pentobarbital-biased lever were reinforced under the VR schedule with the smaller response requirements when pentobarbital was given before the session, and responses on the saline-biased key were reinforced under the VR schedule with the larger response requirements. When saline was administered before the session, the reinforcement contingencies associated with the two response keys were reversed. When responding stabilized under concurrent VR 20 VR 30, concurrent VR 10 VR 40, or concurrent VR 5 VR 50 schedules, pigeons responded almost exclusively on the key on which fewer responses were required to produce the reinforcer. When other doses of pentobarbital and other drugs were substituted for the training dose, low doses of all drugs produced responding on the saline-biased key. Higher doses of pentobarbital and chlordiazepoxide produced responding only on the pentobarbital-biased key, whereas higher doses of ethanol and phencyclidine produced responding only on this key less often. d-Amphetamine produced responding primarily on the saline-biased key. When drugs generalized to pentobarbital, the shape of the generalization curve under concurrent VR VR schedules was more often graded than quantal in shape. Thus, drug discrimination can be established under concurrent VR VR schedules, but the shapes of drug-discrimination dose-response curves under concurrent VR VR schedules more closely resemble those seen under interval schedules than those seen under fixed-ratio schedules. Graded dose-response curves under concurrent VR VR schedules may relate to probability matching and difficulty in discriminating differences in reinforcement frequency.  相似文献   
93.
Data in social and behavioral sciences are often hierarchically organized though seldom normal, yet normal theory based inference procedures are routinely used for analyzing multilevel models. Based on this observation, simple adjustments to normal theory based results are proposed to minimize the consequences of violating normality assumptions. For characterizing the distribution of parameter estimates, sandwich-type covariance matrices are derived. Standard errors based on these covariance matrices remain consistent under distributional violations. Implications of various covariance estimators are also discussed. For evaluating the quality of a multilevel model, a rescaled statistic is given for both the hierarchical linear model and the hierarchical structural equation model. The rescaled statistic, improving the likelihood ratio statistic by estimating one extra parameter, approaches the same mean as its reference distribution. A simulation study with a 2-level factor model implies that the rescaled statistic is preferable.This research was supported by grants DA01070 and DA00017 from the National Institute on Drug Abuse and a University of North Texas faculty research grant. We would like to thank the Associate Editor and two reviewers for suggestions that helped to improve the paper.  相似文献   
94.
应用扇效应技术探讨共享概念的性质对建构拥有关系情境模型的影响。共包括2个实验,探讨在将“多人买1物”句式中的所购“物品”改变为隐含共同地点信息的“物品”条件下,被试对“多人买1物”拥有行为句式的学习是否表现出扇效应。结果表明,当所购物品隐含的相同地点信息的情况下,“多人买1物”的拥有行为句式无论是否具有明确的地点状语,都如同“1人买多物”的句式一样,没有表现出扇效应,与Radvanskv的研究结果不同。据此认为,只有在共享概念是属于情景模型建构的维度信息的情况下,有共享概念的信息才能整合为同一个情景模型。  相似文献   
95.
中国大学生的记忆的自我参照效应   总被引:15,自引:1,他引:14  
戚健俐  朱滢 《心理科学》2002,25(3):275-278
记忆的自我参照效应是指记忆材料与自我相联系时的记忆效果优于其它编码条件的现象,这种优势主要体现在以回忆经验为特征的R反应(“记得”)上。西方一些研究表明,自我参照的记忆成绩优于参照母亲的记忆。本研究以中国大学生为被试,得到参照父亲和母亲的记忆与自我参照有同样好的成绩,显著优于参照名人的记忆,并且父母之间无差异。这支持了独立型/依赖型自我概念模型中的东方文化下的自我概念包括父母的观点。  相似文献   
96.
Four rats were studied with variants of a progressive-ratio schedule with a step size of 6 in which different terminal components followed completion of the 20th ratio: (a) a reversal of the progression, (b) a fixed-ratio 6 schedule, or (c) extinction. Responding in the progressive-ratio components of these schedules was compared to performances under conventional progressive-ratio baselines. Under baseline conditions, postreinforcement pauses increased exponentially as a function of increasing ratio size, whereas running rates showed modest declines. The procedure of linking the progressive-ratio schedule to the reversed progression or to the fixed-ratio component resulted in decreased pausing. Linking the progressive-ratio schedule to the extinction component had the opposite effect, that of producing weakened progressive-ratio performances as evidenced by increased pausing. Subjects whose responses were reinforced on half of the ratios also showed exponential increases; however, pauses were substantially shorter following ratios on which the reinforcer was omitted. The results suggested that progressive-ratio pausing reflects the influence of remote as well as local contingencies.  相似文献   
97.
The emotional Stroop task has been the most widely used task to examine attentional bias to emotionally salient stimuli. In one format of this task, words are presented to participants in a mixed randomized or quasi-randomized sequence. Using a mixed smoking Stroop task, we have previously demonstrated that smokers are slower to respond to words which follow smoking-related words than words which follow neutral words. Here we show that this carry-over effect is present in heroin addicts-but not control subjects-in a heroin Stroop task, and in normal subjects in a stress Stroop task. Thus, the effect generalizes to other populations. In addition, an examination of the studies that have collected data from both mixed and blocked formats provides converging evidence for the presence of carry-over effects. We discuss the implications of the carry-over effect for research using the emotional Stroop task.  相似文献   
98.
Botvinick MM 《Cognition》2005,97(2):135-151
Knowledge concerning domain-specific regularities in sequential structure has long been known to affect recall for serial order. However, very little work has been done toward specifying the exact role such knowledge plays. The present article proposes a theory of serial recall in structured domains, based on Bayesian decision theory and a set of representational assumptions proceeding from recent computational and neurophysiologic research. The theory suggests that the accuracy with which a target sequence will be recalled is influenced by two interacting factors: (1) the 'goodness' of the sequence, i.e. its fit with the sequencing constraints that characterize its source domain, and (2) the sequence's neighborhood relations, i.e. the degree to which it resembles other sequences in the source domain. A specific prediction of the theory is that recall will be relatively poor for target lists with high-goodness near neighbors (the good neighbor effect). This prediction was tested and confirmed in an experiment evaluating recall for sequences based on an artificial grammar.  相似文献   
99.
When participants search for a target letter while reading, they make more omissions if the target letter is embedded in frequent function words than in less frequent content words. Reflecting developmental changes in component language and literacy skills, the size of this effect increases with age. With adults, the missing-letter effect is due to both word function and word frequency. With children, it is unclear whether the growing size of the missing-letter effect across development is due to a larger effect of word function, word frequency, or both because previous studies with children seeking to isolate the influence of word frequency and word function suffer from important methodological limitations. With these methodological limitations eliminated (Experiments 1 and 2), performance in a letter detection task was assessed for children in Grades 1, 2, 3, 4, and 7 as well as for undergraduate students. The results revealed that the influence of word function increases with age, whereas the effect of frequency is fairly stable across ages. Furthermore, normative predictability data collected in Experiment 3 revealed that third graders and undergraduate students were equally good at predicting function slots in a sentence.  相似文献   
100.
Simultaneous visual discrimination in Asian elephants   总被引:3,自引:0,他引:3  
Two experiments explored the behavior of 20 Asian elephants (Elephas aximus) in simultaneous visual discrimination tasks. In Experiment 1, 7 Burmese logging elephants acquired a white+/black- discrimination, reaching criterion in a mean of 2.6 sessions and 117 discrete trials, whereas 4 elephants acquired a black+/white- discrimination in 5.3 sessions and 293 trials. One elephant failed to reach criterion in the white+/black- task in 9 sessions and 549 trials, and 2 elephants failed to reach criterion in the black+/white- task in 9 sessions and 452 trials. In Experiment 2, 3 elephants learned a large/small transposition problem, reaching criterion within a mean of 1.7 sessions and 58 trials. Four elephants failed to reach criterion in 4.8 sessions and 193 trials. Data from both the black/white and large/small discriminations showed a surprising age effect, suggesting that elephants beyond the age of 20 to 30 years either may be unable to acquire these visual discriminations or may require an inordinate number of trials to do so. Overall, our results cannot be readily reconciled with the widespread view that elephants possess exceptional intelligence.  相似文献   
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