人名相关自我加工的时间过程--事件相关电位研究提供的电生理证据

The Time Course of Self-processing Involved in the Detection of One's Own Name:Electrophysiolgical Evidence From ERP

本研究采用事件相关电位技术(ERP)探讨了自我名字加工的神经机制。实验中向被试随机呈现大圆、小圆及名字,被试的任务是辨别大圆和小圆,名字是任务无关刺激。实验结果表明,被试自己的名字引发的P2及P3波幅都显著高于名人的名字及陌生人的名字。与以往研究结果不同,本研究发现了P2波幅上的"自我名字效应",即,人名相关的自我加工不仅表现在晚期成分P3上,同时还表现在早期成分P2上。所以,人名相关的自我加工过程分为早期和晚期两个加工阶段,前一个阶段可能是自动化加工,不需要意识参与,后一个阶段是意识加工。

All previous ERP studies on cerebral mechanisms underlying the detection of our ows names used auditory materials,and some of these studies have problems in the experimental design.So the present study has three purposes：Firstly,to explore the cerebral mechanisms underlying the detection of one＇s own name in the visual channel.Secondly,to make the experimental design closely resemble natural situations.In the present study the subjects performed a big/small circle discrimination task and the names were task-irrelevant stimuli which occurred unpredictably;Thirdly,to control the variables such as repetition time and homogeneity of stimuli and make our experimental design more exact,we contrasted three names;subject＇s own name（SON）,famous name（FN） and unfamiliar name （UFN）,and their probability and physical property were best constant. In the experiment the subjects were instructed to distinguish big and small circles,and the names occurred randomly.The experiment included six blocks of 120 trials,and the subjects could take a brief break between blocks.Within each block,the big and small circles were repeated 40 times respectively,and the subject＇s own name,famous name and unfamiliar name were repeated 10 times respectively, and another ten different filler names which were not analyzed were presented only once.The sequence of all stimuli were randomized for each subject.Each subject was instructed to press the ＂F＂ key if the big circle appeared and to press ＂J＂ key on the keyboard if the small circle appeared,and not to respond to other stimuli except circles.Before the formal experiment,there was a training block in which the training stimuli were circles merely. The results showed that the subject＇s own name（SON） elicited larger P2 and P3 amplitudes than did the famous name（FN） and the unfamiliar name（UFN）.Different from previous ones,the present study discovered the ＂self name effect＂ on P2 amplitude,that is,the results from the present study,suggested that self processing relative to one＇s own name could occurr at not only the later P3 stage but also the earlier P2 stage.Therefore,the significance of the present study is the suggestion that the ＂ self name effect＂ is so potent that it can occurr even at 200ms after stimulus presentation during the P2 stage,and it can be inferred that self processing relative to one＇s own name is underlain by complex mechanisms and may involve two different stages：early and late.The early self processing during the P2 stage which has important significance for individuals＇ interaction with the environment efficiently is automatic,while the late self processing during the P3 stage is conscious.