Babies,television and videos: How did we get here?

Baby media have exploded in the past decade, and children younger than 2 are showing increased use of these baby media. This paper examines the historical evidence of babies’ use of television since the 1950s as well as the various factors that have given rise to the current increase in screen media for babies. We also consider the ubiquitous role of television in American families, the impact of evidence regarding the educational benefits of educational television on preschoolers, and positive parental beliefs about the usefulness of such educational media in preparing young children for schooling. Finally, we examine the theoretical issues of importance for guiding research into the interactions between media exposure and cognitive development, including the role of media in changing the context of children’s development and constraints on the kinds of things babies can learn from screen media. Lastly, we suggest that screen media may indeed be changing the nature of children’s development.     

肿瘤同步放化疗合理应用的思考

同步放化疗的疗效明显优于单一放化疗和序贯放化疗,但毒副作用的叠加效应可引起严重的并发症,甚至造成死亡。本文从同步放化疗的作用机制和临床实践出发,通过对疗效与毒副作用之间的辩证关系进行具体分析,探讨了如何制定合理的肿瘤治疗决策。     

工作记忆中汉字与空间的分离及动态优势半球的ERP效应

测量了14名正常被试完成延迟匹配任务时的事件相关脑电位(ERP)。在刺激消失后的延迟阶段,汉字任务和空间任务均在头皮中前部额区产生P260和晚期正成分(LPC), 在头皮后部顶枕区产生N150和晚期负成分(LNC)。汉字任务的P260表现出右脑优势, 400-800ms时LPC转变为与空间任务相比较的汉字左脑相对优势。空间任务的P260在左右脑无差异,400-800ms时LPC转变为右脑优势。头皮后部无显著差异。本研究提供了工作记忆中汉字与空间信息保持的分离及其优势脑动态变化的ERP证据。     

默读汉字词的脑功能偏侧化成像研究

采用读词名的方法 ,对 12名正常大学生 ,运用功能性磁共振成像技术 (fMRI) ,研究了汉字词及假词视觉识别时的脑功能偏侧化现象。实验结果表明 ,汉字词激活左下额区 (BA4 5 )以及右颞叶 (BA2 1、2 2 )、右枕叶 (BA18) ,而假词除额区外表现出广泛的激活。此结果显示除左脑半球与汉字词加工密切相关外 ,右脑半球在汉字词加工中有一定参与但其确切作用有待进一步研究     

Similar consumption and responding across single and multiple sources of drug

Two experiments were conducted to assess whether total response output and total consumption would be similar when drugs are available from single and multiple sources of reinforcement, as predicted by behavioral economics. In Experiment 1, cigarette-deprived smokers were exposed to a concurrent-chains schedule in which equal fixed-ratio schedules served as the initial links, and different reinforcer magnitudes (i.e., number of cigarette puffs) were arranged across alternatives. After the session, obtained unit price was calculated and imposed in the next session when a different number of puffs was available according to a single fixed-ratio schedule. Thus, the unit price at which cigarette puffs could be earned was yoked within subjects across the single and concurrent-chains schedules. When plotted as a function of unit price, similar consumption and response rates were usually obtained across these schedules. Experiment 2 addressed a weakness of Experiment 1, namely, that responding was allocated exclusively to the larger reinforcer magnitude in concurrent-chains conditions, and therefore this schedule may have functioned as a single schedule. In Experiment 2, subjects were instructed to alternate responding between the two alternative schedules. Instructions produced approximately equal response allocation between the two alternatives. Again, similar consumption and response rates were observed across the single and instructed concurrent-chains schedules. These findings are discussed in the context of direct effects and behavioral economics perspectives of drug self-administration.     

Ratio size and cocaine concentration effects on oral cocaine-reinforced behavior.

Monkeys were given a choice between cocaine solutions and water under concurrent fixed-ratio reinforcement schedules. The operant response was spout contact. Six rhesus monkeys served as subjects. The cocaine concentration was varied from 0.0125 to 0.8 mg/ml, and the fixed-ratio value was varied from 8 to 128. Cocaine maintained higher response rates than did water over a wide range of conditions. Response rate and number of cocaine deliveries per session were inverted U-shaped functions of concentration. These functions were shifted to the right as the fixed ratio was increased. The number of cocaine deliveries was more persistent as fixed-ratio value was increased when the unit dose was larger rather than smaller. Cocaine consumption was analyzed as a function of unit price (fixed-ratio value divided by cocaine concentration), and unit price accounted for between 77% and 92% of the variance in cocaine consumption for individual monkeys. The current data support the claim that a drug's reinforcing effects increase directly with dose and underscore the need to gather parametric data when examining the effects of experimental manipulations on a drug-reinforced baseline.     

The effects of the stimulus-reinforcer correlation in a discrete-trials IRT>t procedure

The correlation between a keylight and food in a discrete-trials, interresponse-time-greater-than 6-sec (IRT>6-sec) procedure was varied by manipulating the rate of response-independent food presentation in the intertrial interval. When the correlation was positive, the rates of pecking in the IRT>6-sec condition were high and food was obtained on only about 5% of the trials. Likewise, responding was maintained at a high rate in yoked birds that received the same presentations of the light and food as the birds in the IRT>6-sec condition. When the rate of reinforcement between trials was equated to or made greater than the rate of reinforcement within trials, the response rate decreased for all birds, and those decreases were considerably larger for the yoked birds. However, the percentage of trials in which reinforced responses occurred under the IRT>6-sec procedure did not increase substantially when the light and food were either uncorrelated or negatively correlated. The percentage of trials in which a reinforcer was obtained increased when the keylight was left on continuously and the discriminative stimulus was not presented on the key. The results show that the stimulus-reinforcer correlation affects responding in the discrete-trials IRT>6-sec procedure, but that the effects of the stimulus-reinforcer correlation vary as a function of whether reinforcement is response-dependent or response-independent. The differences between the effects of response-independent and response-dependent pairings and nonpairings of the light and food are best accounted for in terms of differences in the control of responding by background stimuli.     

四卡问题的视角效应发生机制：领域一般性还是领域特殊性？

视角效应（Perspective Effects)是指四卡问题解决中,当被试从不同的角度对条件规则进行检验时,其选择偏向会在卡片p,q和-p,q之间发生稳定变化的现象。视角效应对四卡问题的解决有重要影响,但其存在条件及发生机制仍存在争议。本研究通过3个实验,探讨四卡问题中的视角效应。实验1和实验2采用混合实验设计,结果表明,转换社会契约、因果规则的四卡问题中,发现视角效应,抽象规则中,提供反例比提供充分必要条件更有利于产生视角效应。实验3在不同视角下研究四卡问题与条件推理的关系。结果表明,四卡问题与条件推理之间不具有逻辑一致性,产生分离现象。总之,视角效应在抽象规则和特定规则中均存在,而提供反例更有利于视角效应的产生。领域一般性或领域特殊性均不能有效解释视角效应的产生,两种机制的综合调节为解释视角效应提供新的角度。     

Accident involvement among Iranian lorry drivers: Direct and indirect effects of background variables and aberrant driving behaviour

Road accident rates among Iranian lorry drivers are considerably high and, according to empirical evidence, aberrant driving behaviours, summed to certain demographic, psycho-social and work-related factors, may explain their accident involvement. Consequently, the main aim of the study was to examine the direct and indirect effects of background variables (i.e. annual mileage, lorry driving experience, demographic and socioeconomic factors) on accident involvement mediated through aberrant driving behaviour among Iranian lorry drivers. A cross-sectional questionnaire survey was conducted in 2012 among 914 lorry drivers in 10 selected provinces in Iran. The 27-item Driver Behaviour Questionnaire (DBQ) was used to measure aberrant driving behaviour. Results from valid observations (n = 785) confirmed a four-factor solution (including ordinary violations, aggressive violations, errors, and lapses) of the DBQ. Errors, ordinary violations and aggressive violations were positively associated with accident involvement. However, lapses were not significantly associated with accident involvement. The results of structural equation modeling (SEM) further showed that, in addition to direct effects of background variables on accident involvement, several variables had indirect effects mediated by three-DBQ factors; ordinary violations, aggressive violations, and errors. Higher age, having more lorry driving experience, having higher educational attainment, and married drivers were indirectly related to less accident involvement. Annual driving mileage and the resting rate of drivers was both directly and indirectly related to accident involvement. Higher income and car ownership were directly related to fewer accidents. Interventions could aim to decrease ordinary violations, aggressive violations and errors among younger, less educated and single lorry drivers. Initiatives targeted to increase the scheduled resting frequency of lorry drivers may also hold promise.     

Reformation Humanism: Reading the Classics in the New Theology

Scholarly discussions on what constitutes Christian humanism in the Renaissance and Reformation periods have typically concentrated on its manifestations before 1536, when Erasmus died. In this period, the old arguments for the reading of the Classics once set out by Basil and Augustine still predominated. Calvin’s teaching on the Fall and the noetic effects of sin, however, provided another basis for the incorporation of pagan thought into Christian learning. Christians who followed Calvin benefited from his precise and comprehensive theological position on the place of worldly knowledge in God’s original creation as a means for justifying their study of the Classics.