Where does "free will" - our ability to make uninfluenced choices - stem from? According to new research from the University of California-Davis, variation in electrical brain patterns may play a part in voluntary decisions.
The research team, including Jesse Bengson, a postdoctoral researcher at the Center for Mind and Brain at UC Davis, explains that patterns of electrical activity that fluctuate across the brain make "neural noise." Past research has indicated that such noise may be important for our perception, cognition and decision-making.
To investigate further, the team conducted a study based on an experiment from the 1970s carried out by Benjmain Libet - a psychologist at the University of California-San Francisco who was also affiliated with the UC Davis Center for Neuroscience.
For his study, he measured the electrical brain activity of participants while they made a decision to press a switch in response to a visual cue.
According to the researchers, just before participants reported that they were going to press the switch, Libet noticed that they demonstrated specific brain patterns.
Decisions could be predicted by preceding electrical brain patterns
In this latest study, the researchers asked 19 volunteers to sit in front of a screen and focus their attention on the center. When a cue symbol appeared on the screen, participants were asked to make a decision to look left or right before reporting their decision. During the activity, their brains' electrical activity was recorded using electroencephalography (EEG).
Researchers could predict a study participant's decision based on their electrical brain patterns that occurred before a decision was made.
The team's findings, recently published in the Journal of Cognitive Neuroscience, revealed that a participant's choice of whether to look left or right could be predicted based on the neural noise that occurred before a cue symbol appeared and before a participant knew what their decision would be.
According to Bengson, the results show how brain activity may influence free will, therefore building on the findings of Libet's research.
However, the team notes that Libet had to rely on participants to report when they were going to make a decision, whereas in this latest study, the team were able to determine at what point decisions were being made in the brain. "We know people aren't making the decision in advance," Bengson adds.
Explaining the team's findings, Bengson told Medical News Today:
"On a moment's notice, we seemingly have the ability to behave in a fashion that is independent of prior circumstances, in what appears to be a violation of the basic laws of physics. We commonly refer to this as free will."
"While of course our purposeful intentions, desires, and goals drive our decisions in a linear cause-and-effect kind of way, our finding shows that our decisions are also influenced by neural noise within any given moment.
This is why often our behavior seems to run counter to our intentions: we make mistakes, etc. But this, the effect of neural noise, might also be how we can generate novel responses to new situational demands. The influence of neural noise on decisions gives our behavior the flavor of free will."
"The easy hypothesis that results from this finding is that the degree to which spontaneous neural activity influences behavior might be diagnostic of a whole spectrum of behaviors," he explained.
"There is likely a healthy happy-medium concerning the signal to noise ratio in the brain. Without enough variation, one might get locked into a pattern and exhibit OCD-like symptoms. Too much noise and one may exhibit behaviors characteristic of ADHD."
Talking to us about the next steps for this research, Bengson said the team plans to explore the relationship between neural noise and decision making further. He noted that as well as the clinical implications, they believe the findings may have implications for research into artificial intelligence.
"If we want to build a computer that mimics human thought and experience, this computer should be creative and it should make mistakes. The introduction of random-spontaneous informational states (neural noise) into attempts at artificial intelligence would be essential," he added.
Earlier this year, Medical News Today reported on a study published in the Journal of Consumer Psychology, which suggested that room lighting may affect decision making.