There Libet’s button experiment, Gazzaniga’s split-brain experiments, and

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There are many questions on
the minds of neuroscientists in modern society, but none may be so prevalent,
so interesting, and so decisive as the free will debate. There has been plenty
of data on both sides of the debate, and scientists fighting to prove their
viewpoints to be more accurate. However, looking at the data presented in
recent years, it becomes harder and harder to prove the existence of free will
and easier to view the world through a probabilistic determinism lens. Some of
the main neuroscience proof behind this concept would be seen in Libet’s button
experiment, Gazzaniga’s split-brain experiments, and Lau’s TMS experiment.

            Now, before diving into the arguments against free will,
let the journey begin with what appears to be a simple question on the surface,
but is vital to this entire debate: what is free will? Free will shall be
defined as the ability for a person to make a conscious choice in a situation
where there is an equal ability to choose any of the option. In simple terms,
if faced with the same choice again, a person with free will would be able to
make a different choice. In addition, the person must have conscious control
over their actions. In neuroscience terms, that would mean that all planning
neuroactivity would occur before all execution activity. If these constrains
are proven to be accurate, then one could say that free will is an accurate
concept that can be applied to the modern world. The last thing to discuss
before getting into the big arguments would be the fact that there will be no
discussion of the philosophy behind whether or not humans have free will or
souls, as that would extend the paper into non-scientific waters. The goal is
to keep the discussion entirely scientific and focused on the neuroscientific
evidence presented towards this debate.

            First off would be one of the largest and most cited
examples against free will, which is Libet’s button experiment. In this
experiment, Libet would set up test subjects in a room with a button and a
clock. He would tell them that they are free to press the button whenever, and
that whenever they decide to press the button, they should do so immediately
while also taking not of the position of the hands on the clock. While they
were performing this, Libet was recording the readiness potential in the
subjects at the same time. Upon conducting the experiment, Libet found that the
human brain unconsciously made a decision before the subject was consciously
aware of it. Therefore, it was possible for the experimenters to predict when
the subject would hit the button before the subject would know when they were
going to hit the button. This is a huge hit against the concept of free will.
If a person’s brain is unconsciously making the decisions before the person is
consciously aware of said decisions being made, that would mean that the brain
is in control, not the person. The person isn’t making the decision as to when
to hit the button, the brain is deciding when to hit the button and eventually,
the person is aware of this decision and is able to act on it. If people did
have free will, Libet would have seen the readiness potential firing at nearly
the exact same time as the decision was being made by the person. This would
show that the processes of the brain and the conscious decision were being made
at the exact same time, leading to the idea that we are consciously able to
make our own decisions. However, the results obtained instead show that we are
only conscious of the decisions that our brain make for us. We do not make the
decisions, we simply attempt to consciously keep up with them as they occur.
Thus, Libet strikes a big blow against free will.

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            Another person who struck a major blow against free will
was Michael Gazzaniga. In fact, he wrote an entire book on the subject of free
will, titled Who’s In Charge? In this book, Gazzaniga makes many very
persuasive points, but some of Gazzaniga’s most impressive work is seen with
split brain patients. Split-brain patients are people who have had their corpus
callosum, the part of the brain that connect the left and the right hemisphere
together and allows them to communicate, surgically severed. These patients
normally needed such an operation in order to help combat severe seizures, but
also presented Gazzaniga with subjects for some of the most impressive free
will experiments to date. In this experiment, Gazzaniga would present a subject
with two images, one presented to the left visual field and one presented to
the right visual field. For most examples, it is said that the left visual
field is a picture of a chicken and the right visual field is a picture of a
snow storm. Due to the general crossing of visual information, the left visual
field information goes to the right hemisphere of the brain while the right
visual field information goes to the left hemisphere of the brain. This is
where the experiment gets interesting. The right hemisphere of the brain has a
section know as the Interpreter, which is responsible for allowing us to
describe why we acted the way we did. It basically attempts to logically
explain all of our brains decisions in a way that makes sense. So, going back
to the experiment, after a moment, the patient is told to use both hands to
select two different items that relate to the photo. Once more the information
crosses over, so the left-hand grabs something related to the chicken, say a
chicken foot, while the right-hand grabs something related to the snow storm,
say a shovel. When questioned about the chicken foot the patient has no issue
simply relating the item straight back to the chicken, but when questioned
about the shovel, the patient does not connect it to the snow storm, but rather
creates a more complex, yet logical reasoning for why they chose the shovel in
relation to the chicken. The interpreter had no access to the information about
the snow storm on the right side so, as a result, had to explain the brain’s
decision not only to the world, but also to themselves, as it related to the
chicken. This, once again, majorly pulls away from the concept of free will. If
we had free will, one would think that we wouldn’t be able to make choices for
reasons that we don’t understand. In addition, if we had free will, one would
think that we wouldn’t be making up reasons for or choices, we would absolutely
know what choices we made, we would know why we made them, and we would be able
to explain it in a way that makes sense. The interpreter brings into question
free will, as why would we need a part of the brain to help explain our choices
if we had free will? If we had free will, we wouldn’t need to explain our
choices to ourselves and others, we would know the choices we made without a
shadow of a doubt and wouldn’t need a part of the brain to make up
explanations. This is once more proof that the brain is acting unconsciously
and then attempting to give us this information later via consciousness. Yet
another strike against free will.

            As we continue to rack up strikes against free will, the
next major argument against free will would be the transcranial magnetic
stimulation experiment done by Lau and company. In this experiment, Lau had
subjects act spontaneously and would apply transcranial magnetic stimulation to
the supplemental motor area immediately after the action. During this process,
the experimenters attempted to record the perceived onset of intention to act
and the perceived onset of the action. The experiment’s results are a little
tricky, so I shall begin by discussing the important concepts involved in this
experiment. When looking at how results should look in terms of free will, one
would expect to see that all experience of the action, including intent and all
neural activity, would be entirely before or during the spontaneous action.
This would help prove that we have conscious control of our actions, due to all
experienced intention being before our actions. They focused on the
supplemental motor area, as this part of the brain is vital for the control of
motion, including intention of motion, which is the part that Lau and company
was most interested in. In proceeding through the experiment, the data found
showed that transcranial magnetic stimulation applied after the spontaneous
action shifted the perceived onset of intention to act backwards in time and
shifted the perceived onset of the actual action forward in time. This would
mean that there is some neural process that occurs after the spontaneous action
that is altering the perceived time of the intention to act and the action in
order to make the two moments feel more connected. Our brain has a post hoc
process that is attempting to make it seem as though the intention to act and
the action are much more closely related in time then they really are, and the
stimulation halts that process and puts into light how large a gap is actually
present between the intention and action. This would also mean that there is
some part of perceived intention occurs after the actual motion occurs, so that
part couldn’t have any impact on the actual action. In other words, part of our
conscious experience of perceived onset is neural activity that occurs after
the action, and therefore cannot possibly have causal effect on the action. If
part of intention occurs after execution, that would mean that we do not have
as much conscious control over our actions as we once thought, and is a huge
issue for those attempting to prove free will to be an accurate way of viewing the

            These three experiments are able to show the scientific
and neurobiological issues with the concept of free will directly, but another
problem facing the world is if we don’t have free will, what would that mean
for the world at large? Some have said that people cannot handle the concept of
not having free will, others have said that it would change society at large.
However, as this is not attempting to get philosophical and sticking to the
facts, the judicial system views all people as having free will and punishments
are as a result of free will. If free will is scientifically proven to be
false, then that would mean that our judicial system would have to be entirely
reevaluated. Another question that comes from the fall of free will would be what
to replace it with. There are a few different options that people have
considered. However, the view that is 
the most accurate representation of the world today would be a concept
known as probabilistic determinism, which in basic terms is the idea that there
is no free will, but rather our lives are controlled by a sequence of cause and
effect that is constantly occurring not only to us, but to the world around us.
These events shape our brain and as a result, also shape our behavior and decision-making
abilities. However, the probabilistic side to it comes from the fact that there
is still some randomness in the universe, from the Heisenberg principle in
physics, where one can know the position or the velocity of a certain particle
at any given time but not both, to Lorenz’ concept of chaos theory and the
butterfly effect, which generally states that a tiny change in initial
parameters, such as a butterfly flapping it’s wings, can have massive
unpredictable results, such as a tornado somewhere far away from the butterfly.
These concepts, as well as many more prove that pre-determinism, or the concept
that all life ever was pre-destinies at the point of the big bang, is most
likely an inaccurate concept. There is enough randomness in day to day life that
this concept of pre-determinism cannot be correct. Rather, the idea that we are
simply the neural results of a probabilistic universe seems to be more accurate
to the scientific evidence presented to the world in modern experiments. 

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