简算策略教学提高小学四年级儿童的计算水平及延迟效应

采用3组平衡组实验设计对小学四年级171名学生进行教学实验,两组实验班学生分别采用讲授式和探究式教学方法进行简算策略计算教学,对照班教师自主进行计算教学。结果揭示：通过专门开设简算策略教学训练课,实验班学生的的计算成绩、计算速度和计算兴趣显著高于对照班学生;实验班的延迟提示与不提示测验无显著差异,未出现策略“利用性缺陷”现象;讲授式和探究式教学方法进行策略教学的效果无明显差异。本研究表明：专门开设策略训练课能提高学生的计算水平和学习兴趣,是有效的和必要的;只要教学方法得当,策略“利用性缺陷”可以避免     

3~5岁幼儿自我延迟满足的发展特点及其中澳跨文化比较

采用实验室实验和情境观察相结合的方法,考察了我国3~5岁幼儿自我延迟满足发展的特点及中澳幼儿自我延迟满足的跨文化差异。研究结果表明：(1) 3~5岁幼儿自我延迟满足平均延迟时间随年龄增长而延长;3岁幼儿使用延迟策略少,4岁幼儿主要使用寻求策略,5岁幼儿主要使用寻求策略和自我分心、问题解决策略,自我言语控制策略在整个幼儿期始终不具有显著优势性。(2) 澳大利亚幼儿自我延迟满足发展水平高于我国同龄幼儿;在延迟策略选择上中澳幼儿既具有差异性,又具有一定的相似性;文化价值观通过教育影响着幼儿自我延迟满足的发展。     

时间贴现的性质与脑机制

时间贴现是指个人对事件的价值量估计随着时间的流逝而下降的心理现象,它是行为选择理论的一个重要组成部分。着重介绍了时间贴现的数学模型（指数模型、双曲线模型族、非双曲线模型）、时间贴现现象和概率贴现现象的联系、延迟兑现与提前兑现时间贴现不对称现象及其理论解释,还讨论了时间贴现现象的神经机制研究。提出了时间贴现未来研究的几个主要问题     

信息保持、短时存贮与执行控制的脑模型

工作记忆的脑机制是认知神经科学研究的重要问题。研究者在分析大量脑成像研究数据的基础上,创建了许多解释工作记忆神经基础的模型。Smith和Jonides发展了工作记忆成分结构模型和贮存与执行加工分离模型。Postle和D’Esposito建构了工作记忆相对表征混合模型,D’Esposito, Postle和Rypma阐述了工作记忆加工阶段动态模型。Fletcher和Henson提出工作记忆额叶分区整合理论。该文通过对上述模型或理论的评价,总结了工作记忆脑成像研究中存在的问题,展望了该研究领域的发展趋势。     

Stimuli inevitably generated by behavior that avoids electric shock are inherently reinforcing.

A molecular analysis based on the termination of stimuli that are positively correlated with shock and the production of stimuli that are negatively correlated with shock provides a parsimonious count for both traditional discrete-trial avoidance behavior and the data derived from more recent free-operant procedures. The necessary stimuli are provided by the intrinsic feedback generated by the subject's behavior, in addition to those presented by the experimenter. Moreover, all data compatible with the molar principle of shock-frequency reduction as reinforcement are also compatible with a delay-of-shock gradient, but some data compatible with the delay gradient are not compatible with frequency reduction. The delay gradient corresponds to functions relating magnitude of behavioral effect to the time between conditional and unconditional stimuli, the time between conditioned and primary reinforcers, and the time between responses and positive reinforcers.     

Antenatal determinants of early childhood talking delay and behavioural difficulties

The determinants of talking delay alone or its comorbidity with behavioural difficulties was examined in 5768 two-year-old members of the Growing Up in New Zealand longitudinal study. Using the MacArthur-Bates Communicative Development inventories and the total difficulties score from the preschool Strengths and Difficulties Questionnaire, a composite measure was created so that children were categorised as showing no language or behavioural concerns (72.5%), behavioural only difficulties (6.1%), language only difficulties (18.1%), and comorbid language and behavioural difficulties (3.3%). Analyses revealed that antenatal factors such as maternal perceived stress, inadequate folate intake, vitamin intake, alcohol consumption during the first trimester and maternal smoking all had a significant effect on child outcomes. In particular, low multivitamin intake and perceived stress during pregnancy were associated with coexisting language and behavioural difficulties. These findings support international research in showing that maternal factors during pregnancy are associated with developmental outcomes in the early childhood period, and demonstrate these associations within a NZ context. Interventions which address maternal stress management and health behaviours during pregnancy could be beneficial to offspring development.     

Self-control in adult humans: variation in positive reinforcer amount and delay.

In five experiments, choice responding of female human adults was examined, as a function of variations in reinforcer amount and reinforcer delay. Experiment 1 used a discrete-trials procedure, and Experiments 2, 3, 4, and 5 used a concurrent variable-interval variable-interval schedule. Reinforcer amount and reinforcer delay were varied both separately and together. In contrast to results previously reported with pigeons, the subjects in the present experiments usually chose the larger reinforcers even when those reinforcers were delayed. Together, the results from all the experiments suggest that the subjects followed a maximization strategy in choosing reinforcers. Such behavior makes it easy to observe self-control and difficult to observe impulsiveness in traditional laboratory experiments that use adult human subjects.     

INCREASING AUTISTIC CHILDREN'S SPONTANEOUS VERBALIZATIONS OF AFFECTION: AN ASSESSMENT OF TIME DELAY AND PEER MODELING PROCEDURES

We assessed the efficacy of time delay and peer modeling procedures in increasing autistic children's spontaneous verbalizations of affection. Four autistic children were taught to spontaneously say “I like (love) you” in response to a hug from a familiar person and their mother. Generalization from a free play training setting to free play outdoors and at home was assessed. Ancillary social and affection behaviors were also observed. Results indicated that the time delay was a quick and effective procedure for all the children. Peer modeling was unsuccessful in teaching the target behavior.     

Diminishing marginal value as delay discounting.

The fundamental law underlying economic demand and exchange is the tendency for value of marginal units to diminish with increasing amounts of a commodity. The present paper demonstrates that this law follows from three still-more-basic psychological assumptions: (a) limited consumption rate, (b) delay discounting, and (c) choice of highest valued alternative. Cases of diminishing marginal value apparently due to pure intensity of reward may plausibly be attributed to the above three factors. The further assumption that maximum consumption rate may vary within and across individuals implies that some substances may be unusually addictive and that some individual animals may be unusually susceptible to addiction.     

Key pecking of pigeons under variable-interval schedules of briefly signaled delayed reinforcement: effects of variable-interval value.

Key pecking of 4 pigeons was maintained under a multiple variable-interval 20-s variable-interval 120-s schedule of food reinforcement. When rates of key pecking were stable, a 5-s unsignaled, nonresetting delay to reinforcement separated the first peck after an interval elapsed from reinforcement in both components. Rates of pecking decreased substantially in both components. When rates were stable, the situation was changed such that the peck that began the 5-s delay also changed the color of the keylight for 0.5 s (i.e., the delay was briefly signaled). Rates increased to near-immediate reinforcement levels. In subsequent conditions, delays of 10 and 20 s, still briefly signaled, were tested. Although rates of key pecking during the component with the variable-interval 120-s schedule did not change appreciably across conditions, rates during the variable-interval 20-s component decreased greatly in 1 pigeon at the 10-s delay and decreased in all pigeons at the 20-s delay. In a control condition, the variable-interval 20-s schedule with 20-s delays was changed to a variable-interval 35-s schedule with 5-s delays, thus equating nominal rates of reinforcement. Rates of pecking increased to baseline levels. Rates of pecking, then, depended on the value of the briefly signaled delay relative to the programmed interfood times, rather than on the absolute delay value. These results are discussed in terms of similar findings in the literature on conditioned reinforcement, delayed matching to sample, and classical conditioning.