客体相似性与个体认知方式对视觉工作记忆表征的影响

In recent years, the study of similarity effect of objects on visual working memory (VWM) representations has aroused much attention, however, there exists much controversy among the study of similarity effect. The mechanism of object similarity effect is still unclear.The present study aims to investigate the mechanism of object similarity effect on VWM by using both behavioral and the event-related potentials (ERP) technique. Four studies will be conducted: The first explores the influence of similarity effect of unique feature on VWM. The second investigates the similarity effect of a two-featured object on encoding of VWM. The third studies influence of the similarity of internal and external features on VWM. The fourth examines the object similarity effect when individuals with different cognitive styles process different VWM tasks. Study 1 includes five experiments. Experiment 1 aims to test the validity of the discrimination of object orientation features similarity in a visual search task. Experiment 2, by using a change-detection task, is to examine the influence of object orientation characteristics similarity on encoding of VWM. Experiment 3 is to analyze the influence of object orientation similarity on retrieval of VWM by using a recognition task. Experiment 4 examines the similarity effect of VWM storage. By using ERP techniques, experiment 5 is to demonstrate the mechanism of positive similarity effect. Study 2 includes five experiments. The study mainly includes two aspects: On the one hand, it tests the effect of similarity on VMW representations when the object has two basic features. On the other hand, it tests the effect of similarity on VWM representations when the object has one basic feature and a detail feature. Study 3 examines the similarity effect of object's internal and external features on VWM representations. Study 4, which aims to explore the reason of positive similarity effect, includes five experiments which are designed to investigate the influence of similarity on VWM representations of object-spatial visualizers by using behavioral and ERP techniques. Through those studies, we hope to further reveal the processing mechanism of object similarity effect on VWM, which can contribute to explain how objects are encoded, and provide new evidence for the object similarity effect on VWM from the perspective of individual difference, and build up the model of relationship between similarity and VWM representations. Knowing the individual differences of the object similarity effect on VWM can provide new evidence for mechanism of object similarity effect on VWM, and facilitate teaching students according to their cognitive styles.

近些年来，客体之间的相似性对视觉工作记忆表征的影响备受研究者关注，但是关于客体相似性效应的研究结论尚存较大争议，相似性效应的产生机制仍不清楚。本项目拟采用行为实验和事件相关脑电位（ERP）技术探讨客体相似性效应的影响因素主要有哪些？客体相似性效应是如何影响视觉工作记忆表征的？重点围绕以下内容开展研究：从客体加工的不同阶段（编码、存储和提取）、客体存储的时间等进一步探讨相似性效应及其机制；客体多特征的相似性以及客体内部特征和外部特征的相似性对视觉工作记忆表征的影响；从个体差异角度探讨相似性对个体视觉工作记忆表征的影响。通过上述研究，重点解决相似性积极效应产生的原因是加工精度的提高还是加工负荷的减少，建立客体的相似性与视觉工作记忆表征之间关系的模型，并从个体差异角度为视觉工作记忆表征中客体相似性的作用机制提供新证据，为教育工作者因材施教提供理论依据。

视觉工作记忆是对视觉信息进行短时存储和操作的容量有限的记忆系统，以往研究发现，当记忆项和探测项之间存在相似性时，客体的相似性损害视觉工作记忆表征；当记忆项之间存在相似性时，客体的相似性促进视觉工作记忆表征。针对以往研究的争议，本项目通过五个研究，采用行为和事件相关脑电位技术，探讨客体相似性和个体认知方式对视觉工作记忆表征的影响，结果发现：（1）对于单特征客体，相似性促进视觉工作记忆编码，而损害视觉工作记忆提取；在编码阶段，相似客体诱发的对侧差异波波幅小于不相似客体。（2）对于多特征客体，在编码阶段，相似性对客体的基本特征、细节特征以及两类特征均产生积极效应。（3）与空间型认知方式个体相比，客体型认知方式个体对不相似客体视觉工作记忆成绩更好，诱发的负慢波波幅较低。（4）其他知觉组织原则与相似性共同影响视觉工作记忆表征，邻近性对相似项目的分组起促进作用，且相似性在视觉工作记忆表征中的效应不会被邻近性所覆盖。（5）与不相似客体相比，相似客体的绑定关系在保持阶段需要更少基于客体的注意；提取阶段探测项和编码阶段目标项的相似性降低注意选择任务的干扰。上述结果表明，相似性对视觉工作记忆加工的编码起积极作用，其产生的机制在于相似性降低工作记忆加工负荷；在保持阶段，相似性能够提高客体表征的稳定性，原因在于相似性促进分组；在提取阶段，相似性损害视觉工作记忆成绩，原因在于记忆项和探测项之间的相似性降低两者之间的区分度，增加信息提取时资源的损耗。同时，在视觉工作记忆表征的过程中，个体认知方式会调节相似性的效应，相比于客体型者，相似性对空间型者的客体信息加工影响更大。本项目深入揭示了视觉工作记忆表征中相似性效应产生的机制以及个体认知方式的作用，建立了相似性、认知方式和视觉工作记忆表征之间关系的模型。上述研究成果发表在The Quarterly Journal of Experimental Psychology、Neuroscience、Memory、《心理科学》和《心理发展与教育》等SCI、SSCI和CSSCI索引期刊上。