Consciousness – Who decides, you or your brain?

If you were to answer the question “What differentiates humans from other organisms on Earth?”, you would probably list a number of things, including the ability of humans to make “free choices” dictated by their consciousness, rather than by something organic. Am I right?

What if someone told you that this is not actually the case? I mean, what if instead of making decisions out of your own will, your brain is “deciding” for you and only after the decision has been made the brain offers you the illusion of conscious act, making you believe that you were the one who made the choice in the first place. But how is it possible that such a dichotomy exists within ourselves, between us and our own brains? Aren’t we our brains? Apparently not!

Now that I (hopefully) managed to capture your attention, I’d like to bore you a bit with some brain structure names and functions, which are necessary in order to begin to understand what’s going to come next.

The frontal lobe contains a few areas, which are involved in planning our movements, decision-making, emotions (usually associated with the decisions we are about to make), repeating previously memorised motor sequences etc. These are the areas involved in voluntary motor control, more specifically, these are the areas that make the difference between reflexes/automatisms and movements or actions we want to pursue. Moreover, all these motor areas are interconnected and also linked to areas that are part of the sensory pathways, such as the parietal , visual, somatosensory and temporal regions (which store different components of visual, auditory and somatic stimuli and are associated with many diseases, such as the inability to feel your own limbs, or recognising faces/objects etc.). 

  • The primary motor cortex (PMC) is mainly involved with the execution of movements. Populations of neurones there encode for the direction and amplitude of the movements we make, prior and during the execution.
  • The 6 pre-motor cortices, the ventral, medial (supplementary) and dorsal areas are mostly involved with planning our movements. They receive inputs from the cerebellum and basal ganglia, which play very important roles in motor learning (like acquiring new skills) and motor planning. Interestingly, different neurones in the pre-motor areas fire action potentials during execution and are inactive during planning of movements and others vice-versa, while some populations of neurones are active for both planning and execution.
  • The prefrontal cortex controls reasoning and decision-making and it is crucial for emotion as well: recall Phineas Gage’s story and how the damage to his prefrontal cortex resulted in a complete change in his personality (article here) as well as how the prefrontal cortex regulates the activity in the hypothalamus and is disrupted in major depressive disorder (article here)
  • The limbic system (amygdala, anterior cingulate cortex, hippocampus) , which are located at the subcortical level and behind the frontal lobe, are involved with emotion, fear and the formation of memories, which are so important in our decision making. And these are just the main players, but there are many other areas, including sensory, which contribute to the planning of our actions and the choices we constantly make. 

In a rather groundbreaking paper, Libet and colleagues showed that the neural processes leading to the initiation of voluntary movements begin several hundred milliseconds before the reported time of conscious intention to make the movements, as in before the subject is aware of the intention to move. They demonstrated using the readiness-potential (negative electrical potential recorded at the scalp) that brain activity involved in decision-making starts before our brains is conscious of the actions. This is also known as ‘preparatory set”.

Dick Swaab proposed that the unconscious brain areas are active before the conscious ones, in order to enable us to make decisions rapidly and effectively, as the conscious systems require time to process and analyse the pros and cons of every decision. And although it is good to consider the consequences of your actions, there are many other decisions about apparently insignificant things, which we make and need to be fast (like for example, running away from a car you see coming). In a dangerous situation, for example, the parts of the brain involved in consciousness might consider the state of your legs, how capable they are of moving fast at that point, your heart rate, blood pressure, levels of energy needed for that action…Well, by the time your brain finishes analysing all these, you will be most certainly dead. 

Another interesting idea Swaab suggested was regarding the reason why we have consciousness of our actions and the things that happen to us in the first place. We need to be conscious of our own experiences so that we learn to avoid negative things in the future and also act upon things that require intervention, such as a wound that needs to be treated. Although the brain seems to be able to plan an action independently of our awareness of it, other brain areas are involved in the execution (as previously mentioned) and the communication between these different parts which fulfil different roles results in consciousness. Exactly why and how evolutionary biology has managed to make us more than just some purely mechanical creatures remains a mystery and still poses many challenges to this field of research, inviting philosophy to have its take on this matter, which many times has proved to be useful.

Swaab also wonders to what extent are criminals, pedophiles, murderers to blame for their bad actions, when it is in fact not them, but their unconsciousness/instincts that dictate them what to do. When considering that people with brain damage resulting in impaired or lack of consciousness (schizophrenia, dementia, multiple sclerosis etc.) sometimes hurt other and are not convicted, you might think that it is right to assume that all criminal acts should be tolerated. However, the difference here is that people not suffering from such disorders are aware of their actions and are capable of stopping them. Although pedophilia is considered a psychiatric disorder, unlike the neurodevelopmental and neurodegenerative ones, it can be controlled by the individual, so that the individual is able to refrain from acting according to his/her instincts. Libet and his team of researchers mention in their study that individuals, although only aware of the intention to make a particular action after the intention has been formed in their brains, are able to “abort the performance” of the action, meaning that they have a conscious “veto”.

They also emphasise the difference between spontaneous, rapidly performed actions, and actions in which a preplanning of the experience occurred (taking into account alternative choices, for instance). This second type of voluntary movements, involving conscious deliberation prior to the act, might actually rely on conscious initiation and control, rather than non-conscious commands. However, this hypothesis has not yet been proved experimentally, in a way the “unconsciousness before consciousness” one has.

So, as it turns out, most of the times we are aware of our brain’s decisions only after they have already been made, and free will seems to be an illusion.

 

References

Libet et al. paper

Antonio Damasio,1995. Decartes’ Error. Vintage Books, pp. 71-73

Dick Swaab, 2014. We are our brains – From the womb to Alzheimer’s. Penguin Books, pp.326-338

Image by Saya Lohovska You can find her arts page here 


2 thoughts on “Consciousness – Who decides, you or your brain?

  1. Indeed, it seems that our entire organism is defined by a large number of laws from both psychological and biological point of view, therefore, my question is: If our subconsciousness is the one that decides before we become aware of that ( and this somehow defines who we are deep down in our ‘unknown dimension’) then what are the factors that ‘define’ our subconsciousness, how do we know what goes there and what doesn’t , what influence us the most and how is it possible for us to release from negative experiences?

    Liked by 1 person

    1. It would take me a while to list all the brain structures that are involved in the subconscious activities, for almost all the brain structures essentially contribute to these; the brain stem, for instance, controls blood pressure, breathing, arousal, pain etc., motor areas send commands to other brain regions and, eventually, to the limbs or other body parts, “telling” them to act in a certain way. And all these processes can take place without us being aware of them.

      Although subconscious processes are controlled by almost the entire brain, everything is highly organized and carefully distributed, due to the links between brain parts.

      To be noted: subconsciousness is not a cognitive function (like memory), as many peoole tend to believe. It is an entire “universe”, comprising many functions.

      Regarding negative experiences, these affect us emotionally only when we perceive them as bad. But bad experiences are important for our survival. A good example is pain – pain is different from nociception, in the sense that the former is the subjective perception of the painful information, received and transmitted further to the brain by the sensory fibres (at this level, painful signals trigger nothing more than nociception). Pain is inhibited by adrenaline and serotonin, secreted by the brainstem and the PAG structure; this is why, when performing a very challenging activity (like playing sports or fighting a battle), individuals perceive much less pain than in normal circumstances; on the other hand, when our bodies are already sensitised by something else (a flu, pain from somewhere else etc.), we feel pain more intensely. Pain is crucial for us, because it makes us aware of the things we should stay away and protect us from, as well us our internal, bodily states.

      Pain is an example of a type of consciousness – being conscious of your own surroundings. But can also emphasize what subconsciousness means: if, for example, we substract our hand from a hot plate because it hurts and in the future we handle hot plates carefully, to prevent getting burnt, but only that, we are only partly conscious. Being conscious of ourselves, a second type of consciousness, in this case, involves realising that we avoid hot plates and why we do this, thinking about that, thinking about the consequences of this action etc.

      Basically, our brains can be conscious, without us being conscious, which can also be reffered as a type of subconsciousness.

      Our subconsciousness determines our behaviours. So, we can agree that, to a certain extent, subconsciousness defines us. When things go the way they should, the brain controls almost everything from basic physiological processes (sleep, sex, eating, urinating etc.) to very complex functions, such as memory or decision-making at a subconscious level. And all these processes happen because of neurotransmitters that are synthesised and released in different parts of the brain and in specific amounts (dopamine, serotonin etc., which are also involved in conscious processes). And also because all brain regions are linked to one another and influence each other.

      When things do no go the way they should, subconsciousness becomes abnormal due to pathology. And pathology, at the neurochemical level, is determined by imbalance in neurotransmitters and hormones, which is triggered by genetic/inherited factors or factors from our own experiences (such as psychological traumas, strokes, car accidents etc).

      At a first glance, we are not much different from machines, which act mechanically in response to external factors; what we have in addition is the fact that we are aware of our actions. The subconsciousness can be seen as the machine, which is by far fascinating and worth studying. But the psychology, the mental illness, the emotions triggered by past and present experiences, the imagination, the “self” seem to depend on consciousness.

      If, without consciousness, our brains seem to act as machines, why don’t all of them act the same, you might ask? We are still very different at the subconscious level, just as we are when we are aware of our surroundings and of ourselves. This is because the experiences we have thoughout our lives are different and they impact our brains differently, and also because our genetic background (another factor influencing subconsciousness) is unique.

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