One of my all time favorite topics is the brain, but more specifically, how the brain's operation results in the human condition. Recently I have been reading about the dichotomy between the conscious and unconscious mind.

The most interesting of which, I think, is a study conducted at the University of Tennesee that investigates the timing of the decision making process while observing brain activity in an fMRI machine (an imaging device that allows researchers to view brain activity in real time) [1].


During the study, researchers placed subjects in an fMRI machine and prompted them to decide to press a button in their left or right hand. Simulatenously, the subject is shown a clock with a rapidly moving second hand. Subjects are asked to identify which number the hand is closest to when they make the decision to press one button or the other. Comparing the data, researchers identified a roughly 200-300ms delay between when the subject reported making the decision and when they actually pressed the button. More interestingly, though, is that the fMRI scanner showed activity in the area of the motor cortex (the part of the brain that drives our movements) 300-500ms before the subjects reported making their decision.

This effect was so prevalent, researchers found they could readily and consistently predict how the subject would react before the subject reported making a decision.

In a separate but related study at Harvard University, Alvaro Pascual-Leone went on to modify the experiment to utilize TMS (transcranial magnetic stimulation, a way to manually stimulate the brain). In the follow up experiment, subjects were asked to think about moving one hand or the other during a specific auditory cue. Following a random pause, a second distinct auditory cue signaled that they should actually move the hand they decided to move. During some tests, researchers determined the hand that the subject intended to move using real time brain imaging and, prior to the second auditory cue, delivered a shock to the subject's motor cortex that would result in the opposite hand moving. When this happened, the subjects were questioned about the change in behavior with researchers noting that the subject's brain activity suggested that they would move their other hand. Consistently the subjects seemingly made up an explanation, stating they changed their minds, or something similar. But, given the brain imaging, it is possible to discerne with reasonable accuracy that this was not the case, and rather, the conscious brain simply tried to rationalize why the decision it made (to move the left hand, for example) did not happen. Moreso, subjects reported feeling completely normal, as if making a decision to move one hand and having the other move instead was normal.

These findings seem to suggest that this is a completely normal state for the brain. That is, that the conscious mind is not the portion of the brain that actually results in decision making.

fMRI scans during these experiments showed the activation of various regions of the brain, showing that the motor cortex was stimulated 300-500ms before the subject reported making a decision, suggesting the decision was made elsewhere in the brain and that the conscious mind, seemingly, was one of the last to know.


From here, I wanted to take some time to expand upon the findings above, but before that I would like to note I am aware the objective of the studies above was to determine brain functionality and not to attempt to support or reject the concept of free will. However, I do believe that these findings can be used for further extrapolation in the discussion of free will.


What would it mean if the findings of these studies actually meant that free will was an illusion at best? We tend to operate under the assumption that our conscious minds are making the decisions we eventually act out, but it seems that the conscious mind is just along for the ride while doing its best to make sense of our actions.

If this is true, it would imply that what we typically consider to be free will simply does not exist. How then do we ultimately formulate our relatively complex actions then? I would like to assert that the brain operates deterministically. That is, given a specific brain state and a set of stimuli, the brain will always product the same output, similar to a computer program.


With a deterministic brain we can be expected to react the same way every time a set of criteria are met. If I were to poke your arm right now, the reaction you would have is the same reaction you would have if we replicated the poke with the exact same brain and the exact same stimuli. That said, it is worth noting that it would be neigh impossible for the physical state of the brain to be the same since brain plasticity (the tendency for the brain to physically change based on actions and memory) has been well documented [2]. But, if you took your brain as it is right now, placed it in a vat and gave it all the stimuli you are currently experiencing, along with my poke, you would likely react the same way you did originally.

To further expand upon this idea - with a brain operating in a deterministic way, every action we take is literally the only action we will ever take because, given a certain state and a certain set of stimuli we will always act the same way.

If this is the case, then regardless of how much you want to think you wouldn't do X or Y, it is ultimately the state of your brain that decides what you will actually do.


If we were to agree that the idea the brain operates in a deterministic way is correct, what would that mean for the idea of free will? Researchers have demonstrated it is not the conscious mind that is first made of aware of decisions, rather, it is looped in on a need to know basis and allowed to make its own narrative. Think about this the next time you take a seemingly random action - why did you do that? Take some time to ponder the reason your conscious mind provides you - does it actually make sense?

Furthermore, consider what this means in terms of law and order. When we punish a criminal for committing a crime, are we punishing the conscious mind or the unconscious mind that likely decided to take the criminal action in the first place? Is this ethical if the brain is truly deterministic, if so, the criminal was incapable of acting in any other way.

What else would be impacted if we were to determine with certainly that our brains operate in a deterministic way?