Nav: Home

The brain-computer duel: Do we have free will?

January 04, 2016

The background to this new set of experiments lies in the debate regarding conscious will and determinism in human decision-making, which has attracted researchers, psychologists, philosophers and the general public, and which has been ongoing since at least the 1980s. Back then, the American researcher Benjamin Libet studied the nature of cerebral processes of study participants during conscious decision-making. He demonstrated that conscious decisions were initiated by unconscious brain processes, and that a wave of brain activity referred to as a 'readiness potential' could be recorded even before the subject had made a conscious decision.

How can the unconscious brain processes possibly know in advance what decision a person is going to make at a time when they are not yet sure themselves? Until now, the existence of such preparatory brain processes has been regarded as evidence of 'determinism', according to which free will is nothing but an illusion, meaning our decisions are initiated by unconscious brain processes, and not by our 'conscious self'. In conjunction with Prof. Dr. Benjamin Blankertz and Matthias Schultze-Kraft from Technische Universität Berlin, 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. Using state-of-the-art measurement techniques, the researchers tested whether people are able to stop planned movements once the readiness potential for a movement has been triggered.

"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. As part of this study, researchers asked study participants to enter into a 'duel' with a computer, and then monitored their brain waves throughout the duration of the game using electroencephalography (EEG). A specially-trained computer was then tasked with using these EEG data to predict when a subject would move, the aim being to out-maneuver the player. This was achieved by manipulating the game in favor of the computer as soon as brain wave measurements indicated that the player was about to move.

If subjects are able to evade being predicted based on their own brain processes this would be evidence that control over their actions can be retained for much longer than previously thought, which is exactly what the researchers were able to demonstrate. "A person's decisions are not at the mercy of unconscious and early brain waves. They are able to actively intervene in the decision-making process and interrupt a movement," says Prof. Haynes. "Previously people have used the preparatory brain signals to argue against free will. Our study now shows that the freedom is much less limited than previously thought. However, there is a 'point of no return' in the decision-making process, after which cancellation of movement is no longer possible." Further studies are planned in which the researchers will investigate more complex decision-making processes.
-end-
*Matthias Schultze-Kraft, Daniel Birman, Marco Rusconi, Carsten Allefeld, Kai Görgen, Sven Dähne, Benjamin Blankertz and John-Dylan Haynes. Point of no return in vetoing self-initiated movements. Proceedings of the National Academy of Sciences of the USA, Dec. 2015. doi/10.1073/pnas.1513569112.

Image caption: Duel against the computer: a participant during the experiment, Copyright: Charité, Carsten Bogler.

Contact:

Prof. Dr. John-Dylan Haynes
Director, Berlin Center for Advanced Neuroimaging (BCAN)
Bernstein Center for Computational Neuroscience
Charité - Universitätsmedizin Berlin
Tel: +49 1525 463 9421
Email: john-dylan.haynes@charite.de

Links:

Prof. Haynes' working group (AG Prof. Haynes)
https://sites.google.com/site/hayneslab/

Charité - Universitätsmedizin Berlin

Related Decisions Articles:

For complex decisions, narrow them down to two
When choosing between multiple alternatives, people usually focus their attention on the two most promising options.
Fungal decisions can affect climate
Research shows fungi may slow climate change by storing more carbon.
How decisions unfold in a zebrafish brain
Researchers were able to track the activity of each neuron in the entire brain of zebrafish larvae and reconstruct the unfolding of neuronal events as the animals repeatedly made 'left or right' choices in a behavioral experiment.
Best of the best: Who makes the most accurate decisions in expert groups?
New method predicts accuracy on the basis of similarity.
How do brains remember decisions?
Mammal brains -- including those of humans -- store and recall impressive amounts of information based on our good and bad decisions and interactions in an ever-changing world.
How we make complex decisions
MIT neuroscientists have identified a brain circuit that helps break complex decisions down into smaller pieces.
Opposites attract and, together, they can make surprisingly gratifying decisions
Little is known about how consumers make decisions together. A new study by researchers from Boston College, Georgia Tech and Washington State University finds pairs with opposing interpersonal orientations -- the selfish versus the altruistic -- can reach amicable decisions about what to watch on TV, or where to eat, for example.
Group decisions: When more information isn't necessarily better
Modular -- or cliquey -- group structure isolates the flow of communication between individuals, which might seem counterproductive to survival.
How do we make moral decisions?
When it comes to making moral decisions, we often think of the golden rule: do unto others as you would have them do unto you.
When more women make decisions, the environment wins
When more women are involved in group decisions about land management, the group conserves more - particularly when offered financial incentives to do so, according to a new University of Colorado Boulder study published this week in Nature Climate Change.
More Decisions News and Decisions Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Listen Again: Reinvention
Change is hard, but it's also an opportunity to discover and reimagine what you thought you knew. From our economy, to music, to even ourselves–this hour TED speakers explore the power of reinvention. Guests include OK Go lead singer Damian Kulash Jr., former college gymnastics coach Valorie Kondos Field, Stockton Mayor Michael Tubbs, and entrepreneur Nick Hanauer.
Now Playing: Science for the People

#562 Superbug to Bedside
By now we're all good and scared about antibiotic resistance, one of the many things coming to get us all. But there's good news, sort of. News antibiotics are coming out! How do they get tested? What does that kind of a trial look like and how does it happen? Host Bethany Brookeshire talks with Matt McCarthy, author of "Superbugs: The Race to Stop an Epidemic", about the ins and outs of testing a new antibiotic in the hospital.
Now Playing: Radiolab

Dispatch 6: Strange Times
Covid has disrupted the most basic routines of our days and nights. But in the middle of a conversation about how to fight the virus, we find a place impervious to the stalled plans and frenetic demands of the outside world. It's a very different kind of front line, where urgent work means moving slow, and time is marked out in tiny pre-planned steps. Then, on a walk through the woods, we consider how the tempo of our lives affects our minds and discover how the beats of biology shape our bodies. This episode was produced with help from Molly Webster and Tracie Hunte. Support Radiolab today at Radiolab.org/donate.