Verbaarschot Ceci, Farquhar Jason, Haselager Pim
Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, The Netherlands.
Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, The Netherlands.
Conscious Cogn. 2015 May;33:300-15. doi: 10.1016/j.concog.2015.01.011. Epub 2015 Feb 14.
In 1983 Libet et al. found that the Readiness Potential (RP) precedes the intention to act by 350ms and the actual movement by 500ms on average. Using our own replication study, we illustrate how seemingly innocuous technical details are actually crucially relevant to the debate surrounding the interpretation of Libet-style experiments. For instance, using one specific method for determining the RP onset actually led to a reversal of Libet's results (i.e., the intention preceded the RP onset) for one of the participants. Claims regarding the causal relation between RP and intention cannot be based on averages, but require individual, case by case analyses, which show no exceptions in the temporal relation between RP and intention. We conclude that, properly speaking, Libet-style results in themselves cannot yet be taken as proof for the type of conclusions that are often formulated regarding the non-existence of free will.
1983年，利贝特等人发现，准备电位（RP）平均比行动意图提前350毫秒出现，比实际动作提前500毫秒出现。通过我们自己的重复研究，我们说明了看似无关紧要的技术细节实际上与围绕利贝特式实验解释的争论至关重要。例如，使用一种特定的方法来确定准备电位的起始点，实际上导致了其中一名参与者的利贝特结果出现逆转（即意图先于准备电位起始点）。关于准备电位与意图之间因果关系的主张不能基于平均值，而需要逐个案例进行分析，这些分析表明准备电位与意图之间的时间关系没有例外。我们得出结论，严格来说，利贝特式的结果本身还不能被视为对关于自由意志不存在的那种经常被提出的结论的证明。
