Does 'free will' stem from brain noise?

Our ability to make choices—and sometimes mistakes—might arise from random fluctuations in the brain's background electrical noise, according to a recent study from the Center for Mind and Brain at the University of California, Davis.

"How do we behave independently of cause and effect?" said Jesse Bengson, a postdoctoral researcher at the center and first author on the paper. "This shows how arbitrary states in the can influence apparently voluntary decisions."

The brain has a normal level of "," Bengson said, as electrical activity patterns fluctuate across the brain. In the new study, decisions could be predicted based on the pattern of immediately before a decision was made.

Bengson sat volunteers in front of a screen and told them to fix their attention on the center, while using electroencephalography, or EEG, to record their brains' electrical activity. The volunteers were instructed to make a decision to look either to the left or to the right when a cue symbol appeared on screen, and then to report their decision.

The cue to look left or right appeared at random intervals, so the volunteers could not consciously or unconsciously prepare for it.

The brain has a normal level of "background noise," Bengson said, as electrical activity patterns fluctuate across the brain. The researchers found that the pattern of activity in the second or so before the cue symbol appeared—before the volunteers could know they were going to make a decision—could predict the likely outcome of the decision.

This video is not supported by your browser at this time.
UC Davis researchers found that the pattern of electrical activity in the brain immediately before making a decision can predict the choice made. This video shows how these experiments are set up. Credit: Andy Fell, UC Davis

"The state of the brain right before presentation of the cue determines whether you will attend to the left or to the right," Bengson said.

The experiment builds on a famous 1970s experiment by Benjamin Libet, a psychologist at UCSF who was later affiliated with the UC Davis Center for Neuroscience.

Libet also measured brain immediately before a volunteer made a decision to press a switch in response to a visual signal. He found brain activity immediately before the volunteer reported deciding to press the switch.

The new results build on Libet's finding, because they provide a model for how brain activity could precede decision, Bengson said. Additionally, Libet had to rely on when volunteers said they made their decision. In the new experiment, the random timing means that "we know people aren't making the decision in advance," Bengson said.

Libet's experiment raised questions of free will—if our brain is preparing to act before we know we are going to act, how do we make a conscious to act? The new work, though, shows how "brain noise" might actually create the opening for free will, Bengson said.

"It inserts a random effect that allows us to be freed from simple cause and effect," he said.

The work, which was funded by the National Institutes of Health, was published online in the Journal of Cognitive Neuroscience.

Bengson is also currently a visiting assistant professor at Bates College, Maine. Co-authors on the paper are Todd Kelley, postdoctoral researcher, Center for Mind and Brain; Professor Jane-Ling Wang and graduate student Xiaoke Zhang, Department of Statistics; and Professor George (Ron) Mangun, Center for Mind and Brain and dean of the Division of Social Sciences at UC Davis.

add to favorites email to friend print save as pdf

Related Stories

How visual attention affects the brain

Jun 26, 2013

New work at the University of California, Davis, shows for the first time how visual attention affects activity in specific brain cells. The paper, published June 26 in the journal Nature, shows that attent ...

Recommended for you

User comments

Adjust slider to filter visible comments by rank

Display comments: newest first

SoylentGrin
3 / 5 (2) Jun 09, 2014
I see this as sort of analogous to high performance fighter jets.
They are inherently unstable. If a pilot tried to fly an F-16, for instance, without the computers it would be impossible. That's the key to their agility: want to turn left? Sure thing, the plane was already going that way. Want to turn right? Cool, the plane was already going that way too.

The noise at the bottom of the brain is like speed, drag and gravity trying to tear the plane of our consciousness apart, and our various cognitive neural nets and structures are the control surfaces that use those forces to drive forward.
It's not a perfect analogy, but anesthetic could block the use of those structures for a time, essentially rendering "us" back to the chaotic noise. Once it wears off, if all goes correctly, our jet emerges from the noise and flies again.
MrVibrating
5 / 5 (2) Jun 09, 2014
As has been noted by so many determinists before, the only definition of 'free will' that can have any objective meaning is 'freedom from coercion (of another will)'...

It's a perfectly agreeable (if not imperative) percept, but a fallacious one nevertheless.

(and FWIW the entity experiencing the illusion, before anyone asks, is probably a function of thalamacortical feed-forward and feedback loops. There's an echo in here..)
RealityCheck
1 / 5 (1) Jun 09, 2014
They should do a modified experiment to distinguish the cases of 'fight or flight' responses such as these immediate response type 'decisions' which involve totally different brain-body decision/pre-processing 'pathways' from 'considered choice' decisions not time-critical or stress-conditioned in such ways as those used in the study which 'over-ride' the 'considered decision' pathways and processing involved when making a truly 'free choice' (and not just the 'conditioned responses' which are self-selectively inbuilt into the present experimental methodology/construct described in the article. The very fact of 'unpredictability' of stimuli and the time-constrained response requirement makes it a more 'fight or flight' type UN-considered response which may have little to do with 'free will' inputs/control by the 'decision maker'.

Remove time constraints and other stress/immediacy factors, allow as much time as the subject wants before making a 'considered decision' then compare cases.
RobertKarlStonjek
5 / 5 (4) Jun 09, 2014
"How do we behave independently of cause and effect?"
No evidence is given for this amazing statement. It appears that the authors are totally ignorant of the relevant science.

There is no evidence whatsoever that any decisions are made "independently of cause and effect".
MrVibrating
not rated yet Jun 10, 2014
@Robert

Quite - furthermore it seems axiomatic that no such evidence could even be possible... acausal determinants are a contradiction in terms!
roldor
not rated yet Jun 14, 2014
I did expect this years ago.