Co-occurring motor,language and emotional–behavioral problems in children 3–6 years of age

PurposeDevelopmental Coordination Disorder (DCD) has been shown to co-occur with behavioral and language problems in school-aged children, but little is known as to when these problems begin to emerge, or if they are inherent in children with DCD. The purpose of this study was to determine if deficits in language and emotional–behavioral problems are apparent in preschool-aged children with movement difficulties.MethodTwo hundred and fourteen children (mean age 4 years 11 months, SD 9.8 months, 103 male) performed the Movement Assessment Battery for Children 2nd Edition (MABC-2). Children falling at or below the 16th percentile were classified as being at risk for movement difficulties (MD risk). Auditory comprehension and expressive communication were examined using the Preschool Language Scales 4th Edition (PLS-4). Parent-reported emotional and behavioral problems were assessed using the Child Behavior Checklist (CBCL).ResultsPreschool children with diminished motor coordination (n = 37) were found to have lower language scores, higher externalizing behaviors in the form of increased aggression, as well as increased withdrawn and other behavior symptoms compared with their typically developing peers.ConclusionsMotor coordination, language and emotional–behavioral difficulties tend to co-occur in young children aged 3–6 years. These results highlight the need for early intervention.     

Choice between single and multiple reinforcers in concurrent-chains schedules

Pigeons responded on concurrent-chains schedules with equal variable-interval schedules as initial links. One terminal link delivered a single reinforcer after a fixed delay, and the other terminal link delivered either three or five reinforcers, each preceded by a fixed delay. Some conditions included a postreinforcer delay after the single reinforcer to equate the total durations of the two terminal links, but other conditions did not include such a postreinforcer delay. With short initial links, preference for the single-reinforcer alternative decreased when a postreinforcer delay was present, but with long initial links, the postreinforcer delays had no significant effect on preference. In conditions with a postreinforcer delay, preference for the single-reinforcer alternative frequently switched from above 50% to below 50% as the initial links were lengthened. This pattern of results was consistent with delay-reduction theory (Squires & Fantino, 1971), but not with the contextual-choice model (Grace, 1994) or the hyperbolic value-added model (Mazur, 2001) as they have usually been applied. However, the hyperbolic value-added model could account for the results if its calculations were expanded to include reinforcers delivered in later terminal links. The implications of these findings for models of concurrent-chains performance are discussed.     

Notes on discounting

In general, if a variable can be expressed as a function of its own maximum value, that function may be called a discount function. Delay discounting and probability discounting are commonly studied in psychology, but memory, matching, and economic utility also may be viewed as discounting processes. When they are so viewed, the discount function obtained is hyperbolic in form. In some cases the effective discounting variable is proportional to the physical variable on which it is based. For example, in delay discounting, the physical variable, delay (D), may enter into the hyperbolic equation as kD. In many cases, however, the discounting data are not well described with a single-parameter discount function. A much better fit is obtained when the effective variable is a power function of the physical variable (kDS in the case of delay discounting). This power-function form fits the data of delay, probability, and memory discounting as well as other two-parameter discount functions and is consistent with both the generalized matching law and maximization of a constant-elasticity-of-substitution utility     

Revisiting the role of bad news in maintaining human observing behavior

Results from studies of observing responses have suggested that stimuli maintain observing owing to their special relationship to primary reinforcement (the conditioned-reinforcement hypothesis), and not because they predict the availability and nonavailability of reinforcement (the information hypothesis). The present article first reviews a study that challenges that conclusion and then reports a series of five brief experiments that provide further support for the conditioned-reinforcement view. In Experiments 1 through 3, participants preferred occasional good news (a stimulus correlated with reinforcement) or no news (a stimulus uncorrelated with reinforcement) to occasional bad news (a stimulus negatively correlated with reinforcement). In Experiment 4 bad news was preferred to no news when the absence of stimulus change following a response to the bad-news option was reliably associated with good news. When this association was weakened in Experiment 5 the results were intermediate. The results support the conclusion that information is reinforcing only when it is positive or useful. As required by the conditioned-reinforcement hypothesis, useless information does not maintain observing.     

DELAYED REINFORCEMENT OF OPERANT BEHAVIOR

The experimental analysis of delay of reinforcement is considered from the perspective of three questions that seem basic not only to understanding delay of reinforcement, but, also, by implication, the contributions of temporal relations between events to operant behavior. The first question is whether effects of the temporal relation between responses and reinforcers can be isolated from other features of the environment that often accompany delays, such as stimuli or changes in the temporal distribution or rate of reinforcement. The second question is that of the effects of delays on operant behavior. Beyond the common denominator of a temporal separation between reinforcers and the responses that produce them, delay of reinforcement procedures differ from one another along several dimensions, making delay effects circumstance dependent. The final question is one of interpreting delay of reinforcement effects. It centers on the role of the response—reinforcer temporal relation in the context of other, concurrently operating behavioral processes.     

初中生学业延迟满足的发展特点及其相关因素研究

用问卷法对194名初中生学业延迟满足的特点及相关因素进行了研究。结果表明:初中学生的学业延迟满足存在年级和性别差异,初二和初三学生的学业延迟满足水平明显低于初一学生,女生比男生的学业延迟满足能力高。课堂目标结构与学业延迟满足有显著关系,任务取向的课堂目标与学业延迟满足呈正相关关系;自我取向的课堂目标与学业延迟满足呈负相关关系。任务价值、自我效能与学业延迟满足呈正相关关系,学业延迟满足与学业成绩呈正相关关系。     

TV or not TV? Does the immediacy of viewing images of a momentous news event affect the quality and stability of flashbulb memories?

The flashbulb accounts of 38 participants concerning the September 11th 2001 terrorist attack reported at both 28 hours and 6 months following the event were examined for quantity, quality, and consistency as a function of the time lapse between first learning of the event and initial viewing of media images. The flashbulb accounts of those who reported seeing images at least an hour after learning of the event differed qualitatively, but not quantitatively, from accounts of participants who reported seeing images at the same time as or within minutes of learning of the event. Delayed viewing of images resulted in less elaborate and generally less consistent accounts across the 6-month interval. The results are discussed in terms of factors affecting flashbulb memory formation and individual differences in connectedness to the event.     

急性心肌梗死患者院前延误的影响因素

急性心肌梗死(AMI)患者的治疗关键在于早期诊断和及时开通闭塞的冠状动脉,患者在发病后能否及早到院接受再灌注治疗,对患者的治疗效果和预后有重要影响.院前延误时间(PDT)即为从患者出现症状至到达医院接受治疗的时间.AMI患者就医大多是延迟的,主要原因是患者不能决定自己的症状是否需要治疗,也就是患者决定就医时间延长.本研究目的是分析造成急性心肌梗死患者院前延误的相关影响因素,为患者赢得最佳治疗时间提供理论依据.     

间隔时间及记忆负荷对信息缺失错误记忆的影响

现场中的信息缺失会影响人类对事件的记忆,这对证人证言研究是非常重要的,但以往对之却鲜有研究.本研究以大学生为被试,运用信息缺失范式,采用视频录像材料,通过2个实验探讨了间隔时间和记忆负荷对错误记忆的影响.结果表明:(1)间隔时间没有影响真实记忆和错误记忆,但信心水平却随着间隔时间的延长而变化;(2)记忆负荷高低没有影响真实记忆却影响了错误记忆,在关键信息呈现条件下,降低记忆负荷可以减少错误记忆的发生;(3)信息性质会影响人们的记忆,关键信息呈现条件下的错误记忆和真实记忆均高于关键信息缺失的条件.