What are the Libet Studies? In 1965, Kornhuber and Deecke used an Electroencephalogram to monitor brain activity prior to wrist flexion. They documented a spike in brainwave activity roughly 800 milliseconds prior to the actual flexing of the wrist. They concluded that this brainwave spike was somehow associated with the initiation of the wrist flexing action. They called this brain activity Bereitschaftspotential, or Readiness Potential (RP). Beginning in 1979 and continuing to 2004, Dr. Benjamin Libet explored RP further with a purpose of finding out where conscious willing occurred in the process of wrist flexion. He wanted to know which came first, the brain activity or the conscious awareness of the decision to flex the wrist. His findings were significant, to say the least. Libet found that RP began approximately 550 milliseconds prior to the flexing of the wrist, but that conscious awareness occurred only 200 milliseconds prior to flexing.[1] In that RP occurred first, many concluded that subjects were not consciously willing their actions--that is, they were not exercising Free Will. Instead, they argued the brain was initiating the actions and the subject was becoming aware of the action sometime later.
What do the Libet Studies show? Opinions are mixed, but many dispute the conclusion mentioned above. Among them, Dr. Alfred Mele, in his book Free: Why Science Hasn’t Disproved Free Will, makes the following objections:
- How does it follow from a spike in brain activity that the "decision" is occurring at the moment the spike begins? Perhaps, this brain activity leads up to a decision at the moment of conscious awareness.[2] He reckons that it could be shown that the same brain activity could occur without the follow-up action. Libet’s study did not measure for this. But, if it were shown that such brain activity occurred without follow-up action, it would show that RP really is just that, a potential readiness to act, but not the determining cause of the act itself.[3]
- Mele points out that Libet “generalized from his findings in this unusual setting to all intentional actions.”[4] What was unusual about this setting, among other things, was that the participants were instructed to act spontaneously. But, Mele argues not all actions are like this. This kind of action is very different from a deliberate or premeditated action. He says, “Maybe when we consciously reason about what to do before we decide, we are much more likely to make our decisions consciously.”[5] And, surely, he is right. Free Will understood as a deliberate, conscious choice is surely something different from wrist-flexing under the instruction of spontaneity. Mele concludes, “But in real-life situations in which we do reason consciously about what to do, the road to action seems quite different. It often seems a lot less arbitrary.”[6]
- Mele also notes that it is a bit unusual to instruct subjects to act unconsciously and then to draw conclusions about the role of consciousness in decision making and to make applications to FW.[7]
- Finally, Mele raises a methodological objection. Citing Haggard and Magno, 1999, Mele explains that using a go-signal form of experiment, subjects upon hearing a tone pressed a button on average 231 milliseconds later. This indicates a proximal intention to action time that is almost exactly the same as the conscious awareness to wrist flexion time documented in the Libet Studies. But, in this case, the intention is formed only at the moment that the go-signal is given. This would suggest that it is possible that the moment of conscious awareness measured by Libet is actually the moment of agent-causal decision.[8] He explains that the participants may very well have been giving themselves a go-signal at the moment of conscious awareness and then acting on that signal. In which case, Mele concludes, the participants would actually be exercising Free Will.
Conclusion These are just a few of the objections raised against the findings of the Libet Studies. Hopefully, these responses suffice to show that the Libet Studies, for whatever they do reveal, fail to disprove Free Will.
[1] Mele, Alfred R. Free Why Science Hasn't Disproved Free Will. Oxford University Press, 2015, p.10.
[2] ibid., 12.
[3] Ibid., 12-13.
[4] Ibid., 13.
[5] Ibid., 15.
[6] Ibid., 15.
[7] Ibid., 16.
[8] Ibid., 21.