Eye movement dysfunction in first-degree relatives of patients with schizophrenia: a meta-analytic evaluation of candidate endophenotypes

Several forms of eye movement dysfunction (EMD) are regarded as promising candidate endophenotypes of schizophrenia. Discrepancies in individual study results have led to inconsistent conclusions regarding particular aspects of EMD in relatives of schizophrenia patients. To quantitatively evaluate and compare the candidacy of smooth pursuit, saccade and fixation deficits in first-degree biological relatives, we conducted a set of meta-analytic investigations. Among 18 measures of EMD, memory-guided saccade accuracy and error rate, global smooth pursuit dysfunction, intrusive saccades during fixation, antisaccade error rate and smooth pursuit closed-loop gain emerged as best differentiating relatives from controls (standardized mean differences ranged from .46 to .66), with no significant differences among these measures. Anticipatory saccades, but no other smooth pursuit component measures were also increased in relatives. Visually-guided reflexive saccades were largely normal. Moderator analyses examining design characteristics revealed few variables affecting the magnitude of the meta-analytically observed effects. Moderate effect sizes of relatives v. controls in selective aspects of EMD supports their endophenotype potential. Future work should focus on facilitating endophenotype utility through attention to heterogeneity of EMD performance, relationships among forms of EMD, and application in molecular genetics studies.     

Observing tutorial dialogues collaboratively: insights about human tutoring effectiveness from vicarious learning

The goals of this study are to evaluate a relatively novel learning environment, as well as to seek greater understanding of why human tutoring is so effective. This alternative learning environment consists of pairs of students collaboratively observing a videotape of another student being tutored. Comparing this collaboratively observing environment to four other instructional methods—one-on-one human tutoring, observing tutoring individually, collaborating without observing, and studying alone—the results showed that students learned to solve physics problems just as effectively from observing tutoring collaboratively as the tutees who were being tutored individually. We explain the effectiveness of this learning environment by postulating that such a situation encourages learners to become active and constructive observers through interactions with a peer. In essence, collaboratively observing combines the benefit of tutoring with the benefit of collaborating. The learning outcomes of the tutees and the collaborative observers, along with the tutoring dialogues, were used to further evaluate three hypotheses explaining why human tutoring is an effective learning method. Detailed analyses of the protocols at several grain sizes suggest that tutoring is effective when tutees are independently or jointly constructing knowledge: with the tutor, but not when the tutor independently conveys knowledge.     

The Heritability of Human Behavior: Results of Aggregating Meta-Analyses

The heritability of human behavior can be estimated through studies comparing MZ and DZ twins and through adoption studies. Meta-analyses have estimated the heritability of intelligence, mental chronometric performance, language ability, anxiety disorders, major depression, antisocial behavior, problem drinking, and smoking. This article presents the aggregation and analysis of these meta-analyses, which included a total of over four hundred samples. The results of the aggregation suggest that about 41% of human behavior is genetically influenced, a percentage that may have evolutionary value. Some significant moderators were found in more than one meta-analysis, including greater heritability (a) in more disordered levels of a behavior for performance on a language-ability test, antisocial behavior, and smoking and (b) in females for antisocial behavior and smoking initiation. The moderator findings raise questions about what might explain the identified differences in level of heritability.     

Law, Convention and Objectivity: Comments on Kramer

Since I do not disagree with the line of argument taken by Kramer and the distinctions he draws between the different ways rules can be ‘mind-independent’, my comments focus on some of the complexities involved in the application of his distinctions. I suggest that law, properly understood as a system of rules/conventions is both existentially and observationally weakly mind independent, but nonetheless objective.

Comprehension of human pointing gestures in young human-reared wolves (<Emphasis Type="Italic">Canis lupus</Emphasis>) and dogs (<Emphasis Type="Italic">Canis familiaris</Emphasis>)

Dogs have a remarkable skill to use human-given cues in object-choice tasks, but little is known to what extent their closest wild-living relative, the wolf can achieve this performance. In Study 1, we compared wolf and dog pups hand-reared individually and pet dogs of the same age in their readiness to form eye-contact with a human experimenter in an object-choice task and to follow her pointing gesture. The results showed that dogs already at 4 months of age use momentary distal pointing to find hidden food even without intensive early socialization. Wolf pups, on the contrary, do not attend to this subtle pointing. Accordingly in Studies 2 and 3, these wolves were tested longitudinally with this and four other (easier) human-given cues. This revealed that wolves socialized at a comparable level to dogs are able to use simple human-given cues spontaneously if the human’s hand is close to the baited container (e.g. touching, proximal pointing). Study 4 showed that wolves can follow also momentary distal pointing similarly to dogs if they have received extensive formal training. Comparing the wolves to naïve pet dogs of the same age revealed that during several months of formal training wolves can reach the level of dogs in their success of following momentary distal pointing in parallel with improving their readiness to form eye-contact with a human experimenter. We assume that the high variability in the wolves’ communicative behaviour might have provided a basis for selection during the course of domestication of the dog.     

Return of experimentally induced chocolate craving after extinction in a different context: divergence between craving for and expecting to eat chocolate

Unlike in fear conditioning, little attention has been devoted to extinction and renewal in appetitive conditioning, despite its relevance for extinction-based addiction treatments. We developed a paradigm, using a specific tray as a conditioned stimulus (CS) for eating chocolate (unconditioned stimulus, US), to investigate the effects of context change on acquisition and extinction of conditioned chocolate craving using an ABA renewal design. In Study 1 (n=32), participants successfully acquired chocolate craving, but unlike what is commonly observed in fear conditioning, craving did not extinguish. In Study 2, we separately assessed craving and US expectancy in a between-subjects design (n=64). US-expectancy data showed acquisition, extinction and renewal in the ABA group. The craving data did not follow this pattern, suggesting different mechanisms for craving and US expectancy. Similarities and differences between craving and US expectancy, as well as practical implications, are discussed.     

皮层运动区和皮层下运动区在运动的认知控制中的作用

运动的认知控制是机体选择适合当前情境的运动的关键。皮层和皮层下运动区的不同脑区分别参与运动认知控制的不同方面, 同时又相互协作以确保各种运动的正确执行。运动前区(PMC)和初级运动区(M1)共同负责感觉与运动之间的转换, M1区、小脑和纹状体共同参与运动的学习和记忆, 辅助运动复合体(SMC)和M1区在运动的计划过程中发挥主导作用。基底神经节和前辅助运动区(pre-SMA)是对运动进行抑制的关键脑区。     

汉语双字词超音段信息在语义激活中的作用

采用眼动方法,通过两个实验考察了汉语双字词超音段信息在语义激活中的作用。结果显示：（1）汉语双字词语义激活过程中,分别改变首字声调和尾字声调对语义激活起到抑制作用,首字声调改变时的抑制作用更大。结果支持了Cohort模型。（2）语义相关词的注视点和注视时间远远多于其控制词,但没有发现词频效应。（3）汉语声调的加工过程与声韵母一样,独立作用于语义激活过程。     

认知风格影响学习迁移的眼动研究

用眼动追踪仪考查中学生认知风格在解决较高相似性与较低相似性几何问题中的影响。结果表明:目标问题与所学内容相似性会影响中学生几何问题解决的速度与成绩,中学生在两类几何问题解决中相关眼动指标存在显著差异;认知风格在不同迁移水平几何问题解决中存在不同的影响。     

当前阅读的眼动研究范式述评

目前, 阅读的眼动研究中常用的实验研究范式包括移动窗口范式、移动掩蔽范式、边界范式、快速启动范式、消失文本范式和视觉—情境范式等。本文详细介绍了这些实验范式的具体实验操作程序、内在的实验逻辑关系及相应的研究成果, 同时总结了在应用各种眼动范式时需要注意的问题。另外, 本文对阅读的眼动研究范式的应用前景进行了展望：(1)眼动研究范式在验证当前阅读的眼动理论模型中的作用; (2)不同眼动研究范式的有效结合及其在场景知觉等研究领域的迁移; (3)眼动研究范式和电生理/脑成像技术的结合; (4)眼动研究范式在中文阅读研究中的应用。