Mediation and Causality at the Individual Level

Within a person-oriented research paradigm the focus is on individuals characterized by patterns of information that are regarded as indivisible wholes. It is then not sufficient to carry out standard variable-oriented mediation analysis. The procedure suggested by von Eye, Mun, and Mair (2009) for pattern-oriented mediation analysis is much better aligned to this person-oriented framework. An important new feature in their approach is that it can detect mediator configurations that prohibit predictor and outcome connections at a pattern level. Two extensions of their procedure are suggested, namely (1) the use of cluster analysis to arrive at the categories and (2) the use of other models for estimating the expected frequencies. It is pointed out that in their context a functional relations perspective might be more relevant than the standard causality perspective.

字频和预存表征对相继记忆效应的影响

采用学习-再认研究范式和事件相关电位方法,研究高频字、低频字、假字和非字的相继记忆效应(Dm效应)。18名大学生为被试,根据其测验结果将刺激分成记住和未记住两类,对相应编码过程的ERPs进行分析。结果表明：（1）真字中发现了相继记忆效应,低频字比高频字的相继记忆效应更大,随后正确再认的ERPs 比不能正确再认的ERPs有更大的晚正成份;（2）非字中的相继记忆效应比真字中的效应更大,出现的时间也较早(140ms~200ms),而假字中没有发现显著的相继记忆效应。这些结果表明,字频是影响相继记忆效应的重要因素,高、低频字的相继记忆效应可能存在不同的神经机制,而预存表征不是相继记忆效应出现与否的前提条件     

非熟练的韩国汉语学习者合成词加工中词优效应的特点

词优效应是语言学习中的一个普遍现象。关于英语母语者和汉语母语者的研究都发现了词优效应。本研究关注非熟练的韩国汉语学习者的中文词汇加工中的词优效应,共两个实验:实验1考察汉字的频率对非熟练的韩国汉语学习者中文词汇加工中词优效应的影响;实验2考察汉字和词之间的语义关系(词汇的结构)对非熟练的韩国汉语学习者中文词汇加工中词优效应的影响。实验1的结果发现,字频并未对非熟练的韩国汉语学习者中文词汇加工中的词优效应产生影响,非熟练的韩国汉语学习者在高频字和低频字的识别中都出现了词优效应,且词优效应的大小没有显著差异。这说明非熟练的韩国汉语学习者在高、低频字的识别中都依赖于自上而下的词汇水平的激活。实验2的结果发现,汉字和词之间的语义关系(词汇结构)影响词优效应,相对于并列结构的词汇加工,在偏正结构的词语加工中更容易出现词优效应。这个结果表明词汇的结构通过影响词水平和字水平之间的交互激活,进而影响中文词汇加工中的词优效应。     

上下文预期在快速场景识别中的作用

本研究首先考察上下文预期是否能够影响快速场景识别,进而通过比较不同空间频率的场景信息来探究上下文预期在快速场景识别不同阶段的作用。共包括3个实验:实验1采用双眼竞争范式,考察对快速呈现场景刺激的主观选择是否受到上下文预期的影响;实验2采用词汇分类与快速场景识别的双任务范式,比较预期与非预期条件下快速场景识别绩效的差异;实验3分别以低频信息(实验3a)和高频信息(实验3b)作为实验材料,探讨预期效应的作用阶段。结果发现:上下文预期可以影响快速场景识别过程中的主观选择与反应绩效;对不同空间频率的场景信息,场景刺激与预期相一致时均可以提高辨别力,但预期对反应偏好的影响只发生在对高空间频率场景信息的加工阶段。因此,上下文预期在快速场景识别不同加工阶段的作用不同,快速场景识别需要结合不同空间频率信息加工的结果。     

图-图干扰范式中语义效应的眼动研究*

采用眼动方法,在图-图干扰范式中探讨了干扰图的频率和语义类型对语义判断的影响。结果发现:(1)语义一致性的主效应显著,与目标图语义一致的干扰图获得的注视时间长于与目标图语义不一致的干扰图,证实了语义干扰效应的存在,与Dell的交互激活模型相吻合。(2)干扰图命名的词汇频率主效应不显著,未发现显著的频率效应,对词汇选择竞争假设提出质疑。     

汉字整体和笔画频率对笔画认知的影响

为考察笔画在汉字认知中的作用,探讨了汉字整体和笔画频率对笔画认知的影响。结果表明：（1）和部件识别类似,笔画认知存在着显著的字劣效应：识别汉字中的笔画比识别单独呈现的笔画反应时明显地长,错误率也大幅度增加,显示了汉字整体对笔画认知的抑制性影响。（2）识别汉字中的笔画的反应时也受背景汉字笔画多少的影响。识别少笔画汉字中的笔画比识别多笔画汉字中的笔画容易。（3）笔画频率对笔画认知也有重要影响,频率高的笔画比频率低的笔画容易识别     

学习、频率和结构方式对汉字知觉干扰效应的影响

知觉干扰存效应是指之前更模糊的刺激的呈现对之后同一模糊刺激的识别的抑制。实验-考察了学习和频率、实验二考察了学习和结构方式对汉字知觉干扰存效应的影响。结果发现：1．汉字与图片一样,不存在材料有限现象,在学习和不学习条件下,汉字识别中均存在知觉干扰效应;2．学习以及频率和结构方式对汉字知觉干扰效应的影响也不显著;3．频率、学习和结构方式对汉字识别的影响显著。这些结果似乎表明当激活超过一定的水平时,和汉字激活水平有关的因素对知觉干扰效应不再起作用。失匹配假说可更好的解释激活水平的作用以及材料有限现象。     

Maternal odor shapes rapid face categorization in the infant brain

To successfully interact with a rich and ambiguous visual environment, the human brain learns to differentiate visual stimuli and to produce the same response to subsets of these stimuli despite their physical difference. Although this visual categorization function is traditionally investigated from a unisensory perspective, its early development is inherently constrained by multisensory inputs. In particular, an early‐maturing sensory system such as olfaction is ideally suited to support the immature visual system in infancy by providing stability and familiarity to a rapidly changing visual environment. Here, we test the hypothesis that rapid visual categorization of salient visual signals for the young infant brain, human faces, is shaped by another highly relevant human‐related input from the olfactory system, the mother's body odor. We observe that a right‐hemispheric neural signature of single‐glance face categorization from natural images is significantly enhanced in the maternal versus a control odor context in individual 4‐month‐old infant brains. A lack of difference between odor conditions for the common brain response elicited by both face and non‐face images rules out a mere enhancement of arousal or visual attention in the maternal odor context. These observations show that face‐selective neural activity in infancy is mediated by the presence of a (maternal) body odor, providing strong support for multisensory inputs driving category acquisition in the developing human brain and having important implications for our understanding of human perceptual development.     

Peer victimization through a trauma lens: Identifying who is at risk for negative outcomes

Peer victimization is a chronic stressor that occurs within the context of peer interactions and has been robustly associated with numerous negative psychological and social adjustment problems. Although increased frequency of peer victimization has been linked to psychosocial problems, few researchers have studied the role of duration and pervasiveness of victimization (i.e., number of places it occurs). The objective of this study was to examine how frequency, duration, and pervasiveness of peer victimization are associated with youth adjustment. Canadian adolescents (N = 879), ages 12–18 completed an online survey about experiences with peer victimization. Youth also answered questions about internalizing problems, distress, relationship quality with family, friends, and adults in their school and community, as well as academic functioning. Data were analyzed using multinomial logistic regression modeling. Both duration and pervasiveness of peer victimization were predictive of increased internalizing problems, distress, relationship problems, and academic difficulties. Duration and pervasiveness of peer victimization were identified as important factors to consider when predicting youth psychosocial adjustment. By asking questions about these situational factors, parents, teachers, and healthcare providers may more effectively identify youth who are at risk for experiencing mental health problems associated with peer victimization.     

运动习惯与社区老年人认知功能的关系

为评估社区老年人运动习惯与认知功能的关系,在北京市通过分层、方便取样的方法选取60岁以上的老年人732名,采用自编调查表收集一般人口学资料及运动习惯情况（包括有无运动习惯,运动频率,运动持续时间）,使用简明精神状态评估量表（MMSE）和北京版蒙特利尔认知评估量表（MoCA-BJ）评估认知功能。结果发现：（1）运动组整体认知功能及视空间定向能力得分均高于无运动组;（2）有无运动习惯可正向预测整体认知功能及视空间定向能力得分;（3）运动持续10年及以上组整体认知功能得分高于运动持续10年以下组。结果表明：相对于无运动习惯的社区老年人,有运动习惯的社区老年人的整体认知功能及视空间定向能力更好;运动持续年数较长,对社区老年人的认知功能起到促进作用。