人脑运动前准备电位（BP）的两种成分

人脑运动前准备电位起始时间之长令研究者费解。本文比较了受指令食指屈曲运动和自我起始食指屈曲运动的ＢＰ。结果显示，ＢＰ在受到指令之前已经开始。显然，指令前那一部分ＢＰ即ＢＰ早期部分与运动无关。本文进一步研究了下意识眨运动，指令眨眼运动和自我起始眨眼运动。发现下意识眨眼运动时，ＢＰ起始时无早期成分，明显较另外两种眨眼运动的ＢＰ为短，表明ＢＰ的早期成分是由于在后两种有意识活动参与的眨眼运动中，心理活动产

TWO COMPONENTS IN BEREITSCHAFTSPOTENTIAL

In this work the BP onsettimes of voluntary movement and instructed movementwere compared.Our results show that there is no significant difference (P>0.05)between BP onsettimes of the two kinds of movement and that BP occurs before the instruction of movement.The early component of BP,i.e.the negstive wave before thepresentation of instruction,had no relationship with movement preparation.For theanalysis of the source of the BP early component,the BP onsettimes of unconscious eyeblink and instructed eyeblink or self-initiated voluntary eyeblink were compared.It wasfound that the BP onsettime of unconscious eyeblink was much shorter than that of thetwo kinds of conscious (P<0. 05) eyeblink.These results suggest that the BP earlycomponent is elicited by psychological factors,rather than the result of the preparatoryprocesses of movements in the blain.