Behavioral and neural correlates of memory selection and interference resolution during a digit working memory task

Neuroimaging studies have shown the involvement of prefrontal and posterior parietal cortexes in regulating information processing. We conducted behavioral and fMRI experiments to investigate the relationship between memory selection and proactive interference (PI), using a delayed recognition task with a selection cue presented during the delay indicating which two of the four studied digits were relevant to the present test. PI was indexed by the response time differences between rejecting probes matching and not matching the no longer relevant digits. By varying the delay intervals, we found that the effect of PI did not diminish, even for cases in which the postcue interval was extended to 9 sec, but was stronger when the precue interval was lengthened to 5 sec. By examining the correlation between PI index and neural correlates of memory selection, we found that stronger PI is predicted by lower selection-related activity in the left inferior parietal lobe, the precuneus, and the dorsal middle frontal gyrus. Our results suggest that activity in the prefrontal-parietal network may contribute to one’s ability to focus on the task-relevant information and may proactively reduce PI in working memory.     

Precedence-effect-induced enhancement of prepulse inhibition in socially reared but not isolation-reared rats

Attention to a prepulse presented shortly before a startling stimulus enhances prepulse inhibition (PPI) of startle in normal people, but not in schizophrenics. Fear conditioning for the prepulse enhances PPI in socially reared, but not isolation-reared, rats. In humans, selective attention to acoustic signals against masking can be facilitated by precedence-effect-induced perceived spatial separation between the signal and the masker. This study investigated whether perceived spatial separation between a prepulse and a noise masker enhances PPI in socially reared rats and isolation-reared rats. The results show that both PPI and conditioning-induced PPI enhancement were larger in socially reared rats than in isolation-reared rats. More important, in socially reared, but not isolation-reared, rats, a further PPI enhancement was induced by precedence-effect-induced perceived separation between a prepulse and a masker only after the prepulse became fear conditioned. Thus, perceived separation facilitates normal rats’ attention to a conditioned prepulse and enhances PPI. Isolation rearing impairs rats’ ability to attend to ecologically significant acoustic events.     

A standardized set of 260 pictures for Modern Greek: Norms for name agreement, age of acquisition, and visual complexity

The appropriate selection of both pictorial and linguistic experimental stimuli requires a previous languagespecific standardization process of the materials across different variables. Considering that such normative data have not yet been collected for Modern Greek, in this study normative data for the color version of the Snodgrass and Vanderwart picture set (Rossion & Pourtois, 2004) were collected from 330 native Greek adults. Participants named the pictures (providing name agreement ratings) and rated them for visual complexity and age of acquisition. The obtained measures represent a useful tool for further research on Greek language processing and constitute the first picture normative study for this language. The picture norms from this study and previous ones may be downloaded from brm.psychonomic-journals.org/content/supplemental.     

Neonatal imitation in chimpanzees (<Emphasis Type="Italic">Pan troglodytes</Emphasis>) tested with two paradigms

Primate species differ in their imitative performance, perhaps reflecting differences in imitative capacity. The developmentally earliest form of imitation in humans, neonatal imitation, occurs in early interactions with social partners, and may be a more accurate index of innate capacity than imitation of actions on objects, which requires more cognitive ability. This study assessed imitative capacity in five neonatal chimpanzees, within a narrow age range (7–15 days of age), by testing responses to facial and vocal actions with two different test paradigms (structured and communicative). Imitation of mouth opening was found in both paradigms. In the communicative paradigm, significant agreement was found between infant actions and demonstrations. Additionally, chimpanzees matched the sequence of three actions of the TC model, but only on the second demonstration. Newborn chimpanzees matched more modeled actions in the communicative test than in the structured paradigm. These performances of chimpanzees, at birth, are in agreement with the literature, supporting a conclusion that imitative capacity is not unique to the human species. Developmental histories must be more fully considered in the cross-species study of imitation, as there is a greater degree of innate imitative capacity than previously known. Socialization practices interact with innate and developing competencies to determine the outcome of imitation tests later in life.     

5岁儿童能够理解假装的心理表征:对Moe任务的质疑

本研究通过三个实验对Lillard的Moe假装任务进行了重复与改进,旨在探讨儿童对假装行为中知识状态作用的理解,进而讨论儿童对假装的心理本质的理解。实验一表明,“是否”问题使得5岁儿童在该任务上表现出肯定回答倾向;实验二表明．当改变提问方式,在问题中提供选择项目后,5岁儿童在该任务上的通过率有显著提高．肯定回答倾向明显减弱;实验三表明,当减少指导语中相互矛盾的信息、明确指出主人公知道某物而不知道另一物以及减弱对未知状态和知道状态的强调的情况下．5岁儿童能根据主人公所知道的事物来推断出其行为是在假装成该事物,能理解到知识状态在假装行为中的作用。这一结果表明5岁儿童能够理解到假装中所隐含的心理表征,Lillard所提出的Moe任务范式低估了儿童对假装的心理本质的理解能力。     

成功老龄化的SOC模型研究综述

本文简单回顾了关于成功老龄化研究的历史,综合阐释其定义及指标,并引入Baltes经典成功老龄化的SOC模型,详细介绍它的原理及其组成部分——选择、优化和补偿,并概述它对老龄化满意度的积极影响,最后总结了该领域研究中尚存的问题。     

英国哲学研究现状及其简要分析

[作者说明]2007年我受国家留学基金委的资助,到英国进行为期半年的学术访问,走访了英国的几所主要大学哲学系,采访了许多英国著名哲学家,查阅了大量英国哲学最新研究资料,参加了在英国召开的各种国际学术研讨会,对英国哲学的研究现状有了进一步的了解。根据我所了解的情况,我对英国哲学的研究现状做出如下简要分析,供参考。     

RBF神经网络在股价预测中的应用

提出了一种基于RBF神经网络的股票价格预测模型。该模型通过对历史股价数据的分析,采用K-均值聚类算法动态确定RBF网络中心,根据梯度下降法进行自适应权值调整。并且根据股价的差异大,时变性强和高度非线性的特点,对RBF网络的学习算法进行了改进,进一步提高了RBF网络的非线性映射能力和自适应能力,最后运用该模型对股票走势进行了预测。     

分配公正、程序公正、互动公正影响效果的差异

以大学生奖学金评比为例,探讨了组织公正各维度影响效果的差异。以661名大学生为被试,采用2×2×2的完全随机设计,以情境故事法（scenarios）呈现刺激,研究了奖学金评比中分配公正、程序公正、互动公正对大学生学习投入、班级荣誉感、班级归属感、与辅导员的关系的影响。结果表明,组织公正三个维度与效果变量之间存在清晰的对应影响关系：分配公正主要影响具体、以个人为参照的效果变量;程序公正主要影响与组织有关的效果变量;互动公正主要影响与上司有关的效果变量。