人脑内不同机制参与视觉图形冲突的处理

Different mechanism in human brain involved in processing conflicting visual shapes

目的 :研究脑内对具有冲突信息的立体图形及平面图形处理的机制。方法 :刺激对由常见的平面图形及立体图形随机组合而成 ,分为四种状态 :a 刺激对由两个完全相同的立体图形组成 ;b 刺激对由两个完全相同的平面图形组成 ;c 刺激对由两个构型不同的立体图形组成 ;d 刺激对由两个构型不同的平面图形组成。受试者的任务 :辨别前后呈现的两个刺激 (第一个刺激S1,第二个刺激S2 )形状是否相同。结果 :在c、d两种状态下 ,可记录到冲突负波N2 70 ,该负波不出现于a、b状态 ,同时 ,N2 70 的最大振幅在c状态下出现在右侧后头部 ,而d状态下则出现在前头部。结论 :脑对具有冲突特征的立体及平面图形具有不同处理机制。

Objective:To study the processing mechanism of the conflicting stereo and plane visual shapes in human brain.Methods:The stimulus pairs consisted of similar plane and stereo shapes and were divided into four conditions:a, The first (S 1) and the second stimulus (S 2) were the same stereo shapes;b,S 1 and S 2 were the same plane shapes;c,S 1 and S 2 were different stereo shapes;d,S 1 and S 2 were different plane shapes. Participants were instructed to discriminate if the two visual stimuli presented in sequence were identical and event-related potential (ERP) was recorded from their scalp.Result:A conflicting negative component N 270 was recorded in condition c and d,which showed the maximal amplitude in the right posterior scalp in condition c and in the anterior scalp in condition d.Conclusion:Different cognition mechanism might be involved in the process of conflicting stereo and plane visual shapes.