ERP Correlates of Form and Rhyme Letter Tasks in Impaired Reading Children: A Critical Evaluation

Event-related potentials (ERPs) were obtained from 15 electrode sites in six average and six impaired reading children, 12 years of age, during visual letter discrimination tasks. Subjects responded to target letters with an enclosed area in the form task and to letters that rhymed with “e” in the rhyme task. Response accuracy was similar between the groups. Reaction time was relatively longer for the impaired group during the rhyme task. At lateral sites, condition differences were evident as greater negative shifts in the rhyme task than the form at 170 and 470 ms as well as a delayed late positivity for the rhyme. In terms of reading ability, the average readers’ ERPs were more negative than those of the impaired group at 270 and 450 ms. Interhemispheric variations were also seen between the groups, with the average readers more negative than the impaired readers at right hemisphere sites. Contrary to expectations, group differences in the ERP did not vary substantially as a function of condition, and task demands were evaluated in view of these findings.     

空巢老人心理健康的现状及研究述评

空巢老人的心理健康引起了国内外研究者们的高度关注,逐渐成为一个热点课题.在综合国内外有关空巢老人心理健康的研究文献后发现,目前,学界对空巢老人的界定并不统一;从其心理健康现状来看,空巢综合症是空巢老人各种身心症状的主要体现,主要受社会支持、性别、婚姻状况、经济收入以及其他一些社会人口学因素的影响.虽然对空巢老人心理健康的研究已取得一些成就,但仍存在一些尚待解决的问题,未来研究应从统一空巢老人的涵义,完善研究方法,深入对其自身内部心理因素的探讨及加强跨文化的比较与借鉴等方面来开展.     

Dynamic orientation cues decrease the viewpoint cost of mental rotation

Mental rotation, as a covert simulation of motor rotation, could benefit from spatial updating of object representations. We are interested in what kind of visual cue could trigger spatial updating. Three experiments were conducted to examine the effect of dynamic and static orientation cues on mental rotation, using a sequential matching task with three-dimensional novel objects presented in different views. Experiment 1 showed that a rotating orientation cue with constant speed reduced viewpoint costs in mental rotation. Experiment 2 extended this effect with a varied-speed rotating orientation cue. However, no such benefit was observed with a static orientation cue in Experiment 3. These findings indicated that a visually continuous orientation cue is sufficient to elicit spatial updating in mental rotation. Furthermore, there may be differences in the underlying mechanisms of spatial updating on the basis of constant-speed rotating cues and varied-speed rotating cues.     

Perceiving and Interacting Affordances: A New Model of Human–Affordance Interactions

This article introduces a new affordance framework for humans and human design. Based on previous important concepts in product design–affordance, signifier, and product semantics, the authors propose three new concepts to illustrate how people perceive affordance. According to the model, perceptual probability of affordance is the probability that the public can perceive a certain affordance; perceptual threshold of affordance is the threshold at which affordance can be perceived by a person and changed by perceptual information; and situations, in which interactions between affordances and people exist, are crucial influences on human–affordance interactions. An illustration of the model and suggestions for further research are provided.     

被遮蔽的"流动"之魂——辩证发展模式自身的辩证法透视

对辩证发展过程的理解总是与"三段式"联系在一起.然而"三段式"作为黑格尔对古希腊辩证法的发掘和改造,并没有达到表现论的成熟境界,其本身还需要进一步发掘.如果剥去"三段式"的日常语言外衣使其形式化,那么,"正反合"的过程就表现为一个以环节为其结构成分的周期链.以辩证否定的眼光来解读这个周期链,可以发现其中蕴涵了无数种变易的可能性,"三段式"只是其中的典型表达式而不是唯一的表达式.于是,辩证发展的模式就由"一个关系式"的阶段进入到"关系式的变易体系"阶段,从而具有了强大的解释功能.     

Hyperactivity and Learning Deficits in Transgenic Mice Bearing a Human Mutant Thyroid Hormone β1 Receptor Gene

Resistance to thyroid hormone (RTH) is a human syndrome mapped to the thyroid receptor β (TRβ) gene on chromosome 3, representing a mutation of the ligandbinding domain of the TRβ gene. The syndrome is characterized by reduced tissue responsiveness to thyroid hormone and elevated serum levels of thyroid hormones. A common behavioral phenotype associated with RTH is attention deficit hyperactivity disorder (ADHD). To test the hypothesis that RTH produces attention deficits and/or hyperactivity, transgenic mice expressing a mutant TRβ gene were generated. The present experiment tested RTH transgenic mice from the PV kindred on behavioral tasks relevant to the primary features of ADHD: hyperactivity, sustained attention (vigilance), learning, and impulsivity. Male transgenic mice showed elevated locomotor activity in an open field compared to male wild-type littermate controls. Both male and female transgenic mice exhibited impaired learning of an autoshaping task, compared to wild-type controls. On a vigilance task in an operant chamber, there were no differences between transgenics and controls on the proportion of hits, response latency, or duration of stimulus tolerated. On an operant go/no-go task measuring sustained attention and impulsivity, there were no differences between controls and transgenics. These results indicate that transgenic mice bearing a mutant human TRβ gene demonstrate several behavioral characteristics of ADHD and may serve a valuable heuristic role in elucidating possible candidate genes in converging pathways for other causes of ADHD.     

Distraction and attitude change: A resolution

Previous studies have shown that distraction may either increase or decrease attitude change. The present experiment, designed to reconcile earlier findings, was based on the hypothesis that distraction should interfere with message reception but also increase yielding to the message. Distraction should thus increase attitude change to a simple message (one which is easily understood but not very convincing), but decrease attitude change to a complex message (one which is difficult to understand but convicing if understood). Subjects beard messages on two topics, sometimes while distracted by a tape recording of music and sometimes not. Message complexity was successfully manipulated for one of the topics. The results support a model of attitude change which considers the effects of independent variables on both reception and yielding.