自然数码奇象记忆法记忆复杂数字的神经机制

本研究采用学习-再认范式和复杂数字记忆材料,考察自然数码奇象记忆法相对于机械记忆法在记忆提取上的优势及神经机制。行为结果表明,自然数码奇象记忆法比机械记忆法的再认准确率更高。事件相关电位分析结果显示,再认提取阶段奇象记忆条件下诱发的N400和N700波幅显著更低,这说明奇象记忆提取更容易。在自然数码奇象记忆条件下,正确再认旧数字诱发的前额区、左顶枕叶区及中顶枕叶区N700成分与使用自然数码奇象记忆有关。本研究表明,采用自然数码奇象记忆可以减少或跨越语义加工,从而提高个体对材料的记忆效率。     

创造力产生过程中的神经振荡机制

创造力究竟是怎么产生的, 目前尚未得出一致的结论。神经电生理技术因其高时间分辨率, 可以准确地揭示创造力产生进程中的神经振荡机制, 从而帮助人们更深刻地理解创造力的本质。近年来的研究发现, 单节律alpha神经振荡会随着创造力的增加而增强, 这反映了创造力产生过程中的内部信息加工需求增加、自上而下的抑制控制增强。同时, 多频段神经振荡交叉节律耦合体现了创造性产生过程中额叶、颞叶和顶叶等多脑区之间信息交流的动态变化。未来研究应该以整合理论框架为基础, 结合多层次多方法的研究工具, 引进更生态化的数理计算方法, 并利用计算神经科学建模来预测个体创造力发展趋势, 从而全面深刻地认识创造力的本质。     

线索冲突情境下幼儿对不同领域知识的选择性信任特点

探讨幼儿在准确性线索和共识线索冲突情境下对自然与社会领域知识的选择性信任特点。实验1探究幼儿在线索冲突情境下对自然领域知识的选择性信任,选取88名4~6岁幼儿,采用对物品命名的方法,结果发现4岁幼儿依据共识线索进行信任判断,而5~6岁幼儿依据准确性线索进行信任判断;实验2探究幼儿在线索冲突情境下对社会领域知识的选择性信任,选取94名4-6岁幼儿,采用对人格特质命名的方法,结果发现4岁幼儿依据共识线索进行信任判断,5岁幼儿对两类线索没有做出偏向性选择,6岁幼儿依据准确性线索进行信任判断。实验3采用被试内设计,探讨5岁幼儿对两个领域知识的选择性信任,验证了实验1和实验2的相关结果。结论:在线索冲突情境下幼儿对不同领域知识的选择性信任具有不同的年龄发展特点。     

Is visual short-term memory object based? Rejection of the "strong-object" hypothesis

Is the capacity of visual short-term memory (VSTM) limited by the number of objects or by the number of features? VSTM for objects with either one feature or two color features was tested. Results show that capacity was limited primarily by the number of colors to be memorized, not by the number of objects. This result held up with variations in color saturation, blocked or mixed conditions, duration of memory image, and absence or presence of verbal load. However, conjoining features into objects improved VSTM capacity when size-orientation and color-orientation conjunctions were tested. Nevertheless, the number of features still mattered. When feature heterogeneity was controlled, VSTM for conjoined objects was worse than VSTM for objects made of single features. Our results support a weak-object hypothesis of VSTM capacity that suggests that VSTM is limited by both the number of objects and the feature composition of those objects.     

Spatial context learning in visual search and change detection

Humans conduct visual search more efficiently when the same display is presented for a second time, showing learning of repeated spatial contexts. In this study, we investigate spatial context learning in two tasks: visual search and change detection. In both tasks, we ask whether subjects learn to associate the target with the entire spatial layout of a repeated display (configural learning) or with individual distractor locations (nonconfigural learning). We show that nonconfigural learning results from visual search tasks, but not from change detection tasks. Furthermore, a spatial layout acquired in visual search tasks does not enhance change detection on the same display, whereas a spatial layout acquired in change detection tasks moderately enhances visual search. We suggest that although spatial context learning occurs in multiple tasks, the content of learning is, in part, task specific.     

Associative learning improves visual working memory performance

The ability to remember visual stimuli over a short delay period is limited by the small capacity of visual working memory (VWM). Here the authors investigate the role of learning in enhancing VWM. Participants saw 2 spatial arrays separated by a 1-s interval. The 2 arrays were identical except for 1 location. Participants had to detect the difference. Unknown to the participants, some spatial arrays would repeat once every dozen trials or so for up to 32 repetitions. Spatial VWM performance increased significantly when the same location changed across display repetitions, but not at all when different locations changed from one display repetition to another. The authors suggest that a major role of learning in VWM is to mediate which information gets retained, rather than to directly increase VWM capacity.     

What kind of memory supports visual marking?

In visual search tasks, if a set of items is presented for 1 s before another set of new items (containing the target) is added, search can be restricted to the new set. The process that eliminates old items from search is visual marking. This study investigates the kind of memory that distinguishes the old items from the new items during search. Using an accuracy paradigm in which perfect marking results in 100% accuracy and lack of marking results in near chance performance, the authors show that search can be restricted to new items not by visual short-term memory (VSTM) of old locations but by a limited capacity and slow-decaying VSTM of new locations and a high capacity and fast-decaying memory for asynchrony.     

Top-Down Attentional Guidance Based On Implicit Learning of Visual Covariation

The visual environment is extremely rich and complex, producing information overload for the visual system. But the environment also embodies structure in the form of redundancies and regularities that may serve to reduce complexity. How do perceivers internalize this complex informational structure? We present new evidence of visual learning that illustrates how observers learn how objects and events covary in the visual world. This information serves to guide visual processes such as object recognition and search. Our first experiment demonstrates that search and object recognition are facilitated by learned associations (covariation) between novel visual shapes. Our second experiment shows that regularities in dynamic visual environments can also be learned to guide search behavior. In both experiments, learning occurred incidentally and the memory representations were implicit. These experiments show how top-down visual knowledge, acquired through implicit learning, constrains what to expect and guides where to attend and look.     

感恩与听障学生亲社会行为的关系：有调节的中介模型

本研究探讨了感恩与听障学生亲社会行为的关系,并检验生活满意度的中介效应以及性别对中介效应的调节作用。采用青少年感恩量表、生活满意度量表以及长处和困难量表对392名听障学生进行调查,结果显示：（1）感恩显著正向预测听障学生的亲社会行为;（2）生活满意度在感恩与听障学生亲社会行为之间起部分中介作用;（3）该中介作用受到性别的调节,即生活满意度只在听障男生的感恩和亲社会行为之间起中介作用。