Navigation Links
Unconscious decisions in the brain
Date:4/14/2008

This release is available in German.

Already several seconds before we consciously make a decision its outcome can be predicted from unconscious activity in the brain. This is shown in a study by scientists from the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig, in collaboration with the Charite University Hospital and the Bernstein Center for Computational Neuroscience in Berlin. The researchers from the group of Professor John-Dylan Haynes used a brain scanner to investigate what happens in the human brain just before a decision is made. "Many processes in the brain occur automatically and without involvement of our consciousness. This prevents our mind from being overloaded by simple routine tasks. But when it comes to decisions we tend to assume they are made by our conscious mind. This is questioned by our current findings." (Nature Neuroscience, April 13th 2008)

In the study, participants could freely decide if they wanted to press a button with their left or right hand. They were free to make this decision whenever they wanted, but had to remember at which time they felt they had made up their mind. The aim of the experiment was to find out what happens in the brain in the period just before the person felt the decision was made. The researchers found that it was possible to predict from brain signals which option participants would take already seven seconds before they consciously made their decision. Normally researchers look at what happens when the decision is made, but not atwhat happens several seconds before. The fact that decisions can be predicted so long before they are made is a astonishing finding.

This unprecedented prediction of a free decision was made possible by sophisticated computer programs that were trained to recognize typical brain activity patterns preceding each of the two choices. Micropatterns of activity in the frontopolar cortex were predictive of the choices even before participants knew which option they were going to choose. The decision could not be predicted perfectly, but prediction was clearly above chance. This suggests that the decision is unconsciously prepared ahead of time but the final decision might still be reversible.

"Most researchers investigate what happens when people have to decide immediately, typically as a rapid response to an event in our environment. Here we were focusing on the more interesting decisions that are made in a more natural, self-paced manner", Haynes explains.

More than 20 years ago the American brain scientist Benjamin Libet found a brain signal, the so-called "readiness-potential" that occurred a fraction of a second before a conscious decision. Libet's experiments were highly controversial and sparked a huge debate. Many scientists argued that if our decisions are prepared unconsciously by the brain, then our feeling of "free will" must be an illusion. In this view, it is the brain that makes the decision, not a person's conscious mind. Libet's experiments were particularly controversial because he found only a brief time delay between brain activity and the conscious decision.

In contrast, Haynes and colleagues now show that brain activity predicts even up to 7 seconds ahead of time how a person is going to decide. But they also warn that the study does not finally rule out free will: "Our study shows that decisions are unconsciously prepared much longer ahead than previously thought. But we do not know yet where the final decision is made. We need to investigate whether a decision prepared by these brain areas can still be reversed."


'/>"/>

Contact: Prof. Dr. John-Dylan Haynes
haynes@bccn-berlin.de
49-302-093-6762
Max-Planck-Gesellschaft
Source:Eurekalert

Related biology news :

1. Decisions on the second round of the Excellence Initiative announced
2. Cilia: small organelles, big decisions
3. Brain study may lead to improved epilepsy treatments
4. Learning and the brain
5. Can micro-scaffolding help stem cells rebuild the brain after stroke?
6. Scientists ask whether microscaffolding can help stem cells rebuild brain after stroke damage
7. Your babys brain on drugs (and alcohol and tobacco)
8. Autism Speaks collaborates on grant with the Allen Institute for Brain Science and autism expert
9. Veterinary college researcher studying brain tumors in people and animals
10. Harvard researchers publish MRI images of genes in action in the living brain
11. Yerkes researchers identify language feature unique to human brain
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:11/19/2016)... -- Securus Technologies, a leading provider of civil and ... and monitoring, announced today that it has offered a ... independent technology judge determine who has the largest and ... calling platform, and the best customer service. ... what we do – which clearly is not the ...
(Date:11/16/2016)... Nov. 16, 2016 Sensory Inc ., ... security for consumer electronics, and VeriTran , ... retail industry, today announced a global partnership that ... to authenticate users of mobile banking and mobile ... software which requires no specialized biometric scanners, ...
(Date:11/14/2016)... Inc. ("xG" or the "Company") (Nasdaq: XGTI, XGTIW), a ... challenging operating environments, announced its results for the third ... conference call to discuss these results on November 15, ... Key Recent Accomplishments The ... Vislink Communication Systems. The purchase is expected to close ...
Breaking Biology News(10 mins):
(Date:12/8/2016)... SAN DIEGO , Dec. 8, 2016 /PRNewswire/ ... presented demonstrating the role of the Breast Cancer ... stage, ER+ breast cancer are most at-risk for ... therapy. Data include results from three studies advancing ... provide information related to tumor biology and inform ...
(Date:12/8/2016)... , December 8, 2016 ... für Molekulargenetik, erweitert seine Palette an anpassbaren SureSeq™ ... Custom FH Panels, das ein schnelles und kostengünstiges ... Das Panel bietet eine Erkennung von Einzel-Nukleotid-Variationen (Single ... mit einem einzigen kleinen Panel und ermöglicht eine ...
(Date:12/8/2016)... San Francisco, CA (PRWEB) , ... December 08, ... ... and Oculus as finalists in the World Technology Awards. uBiome is one of ... were received across all categories. , In addition to uBiome, companies nominated as ...
(Date:12/8/2016)... , Dec. 8, 2016 Savannah ... remediation technologies and selected NewTechBio,s NT-MAX Lake ... microbial based beneficial bacteria, in conjunction with Hexa ... correct deficiencies with National Pollutant Discharge Elimination System ... has experienced a steady history of elevated pH ...
Breaking Biology Technology: