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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