Do we have Free Will? An Update on Libet’s Experiment

Conceptual image of a businessman holding big hammer

The existence of “free will” was thrown into question in a famous study conducted by Benjamin Libet in the 1980s in which he demonstrated that his subjects responded to stimuli before they were even aware of them. A person’s brain records precursor activity to moving an arm before that person consciously decides to do it. Though some researchers such as Daniel Dennett have cast doubt on the validity of the experiment, it is still quoted as demonstrating that consciousness is an illusion; our “decisions” are illusions too and our actions are dictated by unconscious neurological processes. Free will doesn’t exist despite our feeling that it does.

A team of researchers from Charité’s Bernstein Center for Computational Neuroscience, led by Prof. Dr. John-Dylan Haynes, has now taken a fresh look at this issue and published their results in a recent  “Proceedings of the National Academy of Sciences”.

Prof Haynes said,  The aim of our research was to find out whether the presence of early brain waves means that further decision-making is automatic and not under conscious control, or whether the person can still cancel the decision, i.e. use a ‘veto’, explains Prof. Haynes. 

In the experiment, nicknamed “the brain-computer duel”, subjects engage with a game to “beat the computer”. A computer, using their brain signals tries to predict their decisions, and the subjects try to actively intervene in those decisions. The experiment showed that subjects were able to beat the computer by consciously cancelling a response to a stimulus. The study also suggests that there is a “point of no return” beyond which the conscious mind cannot cancel a movement.

A person’s decisions are not at the mercy of unconscious and early brain waves, Haynes added.  They are able to actively intervene in the decision-making process and interrupt a movement

Perhaps our subjective experience, that we have free will and can make decisions, describes reality after all.

For more information: Neuroscientist Paul Broks on Free Will on the SciMed website.