Wednesday, October 18, 2017

Free Will vs. Neuroscience

A major difference between animals and humans is the human capacity to make choices: the human free will. What would happen if science was able to prove that humans lack free will? What if human choices are simply the brain acting and making decisions depending on the environment? These kinds of questions relate to the branch of science called neuroethics. Beside dealing with the ethics of neuroscience, neuroethics also deals with the intersection of neuroscience and philosophy. Research done by Benjamin Libet opened up the possibility of there being a lack of free will which arose many questions. Libet’s research showed that the brain has a “readiness potential” which is defined as an activation of the brain several hundred milliseconds before the conscious decision of the participant when deciding whether or not to perform a wrist flexion.
Following Libet’s research, a scientist named Chun Siong Soon, “investigated which regions of the brain predetermine conscious intentions and the time at which they start shaping a motor decision”. In the experiment, participants were asked to press a button, right or left, whenever they felt the need to. Participants were also asked to remember the letter shown when their decision was made. Using functional magnetic resonance imaging (fMRI) the activity of the brain was measured during the experiment. It was seen that the motor decision while the participant was performing the act was located on the primary motor cortex and the SMA. Furthermore, seven seconds before these regions were activated the frontopolar cortex was active, followed by the activation of the precuneus into the posterior cingulate cortex.
Furthermore, the research also aimed to discover whether it was possible to predict which side, left or right, the participants where going to chose. To perform this, the patterns shown in the fMRI were located and by using statistically pattern recognition techniques it was possible to predict the outcome with a 60% accuracy.
While the research just mentioned caused a lot of disturbances in society, neuroscience has not yet proved the lack of existence of free will. The article written by Christian Jarrett titled “Neuroscience and Free Will Are Rethinking Their Divorce” talks about how Libet’s findings and the ones who followed do not necessarily discard free will. While Jarrett does not negate the existence of the “readiness potential”, he introduces the idea of “free won’t”. This concept was introduced by a German neuroscientist that defines “free won’t” as the ability that humans have to veto the subconscious “readiness potential”. Participant were asked to press a pedal when the green light was shown and press another pedal when the red light was shown, which veto the first action. Furthermore, the computer would detect the “readiness potential” and turn the red light on in consequence. The findings showed that indeed we are capable to veto that unconscious preparatory motor signal. Jarrett debates that despite there is activity in the brain before we are conscious of our action we are still using our free will by deciding to veto the action or not. Therefore, it is not possible to say that humans’ actions are purely our brains deciding for us.
Together with the fact that we are capable to veto our brain activity to perform something we must take into consideration that the task performed in both Libet’s and Soon’s research by the participants was rather simple. Decisions can be classified into Type A and Type B. Type A decisions are those in which there is a lot more thinking behind them while Type B decisions are those that are made quickly. In order to determine whether humans have free will or not, both Type A and Type B must be tested.
There is no doubt that the brain makes some decisions and we are unconscious of it, for the “readiness potential” does exist. Despite all these findings, neuroscience has not negated the existence of free will.

Work Cited
Jarrett, Christian. “Neuroscience and Free Will Are Rethinking Their Divorce”. 03/02/16. Science of Us. 14/10/17. Web

Soon, Chun Siong. “Unconscious determinates of free decisions in the human brain”. 2008. Nature Neuroscience. Nature Publishing Group. 09/10/17. PDF

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