The Libet Awareness Of Initiation of Action Study – Do We Have Free Will Or Are We Slaves To Our Subconscious

At a meeting of the South African Council of Deans which I attended earlier this week, what struck me most about the day, apart from the great discussions and wisdom of the wise folk I interacted with, was a bowl of popcorn on the table in front of me and my reaction to it. After having a few pieces of popcorn, I said to myself that that was enough, and I focussed back on the erudite discussion going on around me. But, seemingly without any control from me, my hand reached out and picked up more popcorn for me to eat on several occasions, and it felt like my hand was acting in a disembodied way and against my wishes. This reminded me of a great article by my mentor during the time I worked at the National Institutes of Health in Washington DC a few years ago, Dr Mark Hallett, one of the most highly cited and world renowned neurologists and motor control researcher, in which he described a similar scenario (in his case it was a bowl of peanuts). In his article, Mark proposed that ground-breaking research work by Dr Benjamin Libet performed a few decades ago perhaps explained what was happening in such examples where we feel that we are not in control of our body’s actions, and whether we ever have free will in any of the activities which we initiate and perform during our daily lives.

Benjamin Libet was a neuroscientist who worked in the Physiology Department at the University of California in San Francisco, and was interested in brain function, particularly the neural activity and sensation thresholds associated with the awareness of intention to act during motor (muscle controlled) tasks. He performed a classic experiment in the 1970’s where he used an electroencephalogram (EEG), which monitors electrical activity emanating from the tissues of the brain, an electromyogram (EMG), which monitors electrical activities of muscles when they move, and timing devices to assess when participants in his trial became aware of their intent to move their finger, when brain activity in the motor cortex and other areas of the brain changed associated with the planned finger movement, and when the finger actually moved after the participant initiated the movement. Libet asked the study participants to decide themselves when to move their finger, so they would be in control of the initiation of the finger movement, rather than telling them when to move their finger, which was crucial to the trial’s outcome from an agency / control perspective, which was what the study was all about.

The participants became aware of their intent to move their fingers approximately 300 milliseconds prior to the movement of the fingers actually occurring, as objectively measured by the onset of EMG activity in the muscles of the fingers. Two further findings of the study were firstly that electrical brain activity, as measured by EEG activity in the motor and pre-motor areas of the brain, started changing approximately 1050 milliseconds prior to the actual movement of the finger (this early EEG activity prior to a muscle movement is generally known as a Bereitschaftpotential, which is the German word for ‘readiness potential’), which was well before the participants became ‘aware’ of their intention to act / decision to move their finger; and secondly that the ‘awareness’ of the finger movement itself, as opposed to the awareness of the intent to move it, was described by the participants to have occurred approximately 90 milliseconds prior to the finger actually moving. The first finding that there was brain activity in the movement control areas of the brain even before the participants became aware of the decision to move their finger indicates that subconscious brain activity occurred that controlled the finger movement before conscious ‘intent to act’ decisions occurred. Even more astonishing, the second finding that the ‘awareness’ of movement of the finger occurred prior to the movement actually occurring suggested that this ‘awareness’ of finger movement was ‘pre-dated’ by the brain to this time point and was not related to the actual physical movement of the finger itself – in other words the conscious awareness of the movement was ‘painted in’ by the brain to the time when the brain ‘thought’ it was the appropriate time. This finding indicates that our conscious awareness of movement appears to be a ‘figment of our imagination’, or more specifically, an artificial construct generated by unconscious regulatory processes.

Libet and his colleagues concluded from his experiments that unconscious control processes regulate most of our activity, and that conscious awareness of intent is a derivative of these unconscious control processes, and further that free will is an illusion created by them. This study and its conclusions generated a huge amount of interest, and does so to this day, given it was the first time the concept of ‘free will’ had been assessed in an objective way, and had been shown to not occur during the testing conditions of the trial. While a number of research folk, and in particular a number of philosophers (philosophers love to argue about free will, and believe concepts such as free will and consciousness to be very much in their domain of study, even if they don’t often do any objective research on these topics themselves), have attempted to negate or pick holes in the study design, the findings have been replicated on a number of occasions, with further studies showing that brain activity in other brain areas such as the frontal cortex can occur even earlier than that which Libet demonstrated in the motor and pre-motor cortex prior to movement. These findings suggested that free will appears to be the ‘slave’ of the unconscious, or even further that it does not occur in activities we believe we ‘control’. While this study examined simple finger movement, there are a number of other ‘physical’ examples of unconscious control activity which Mark Hallett suggested support Libet’s finding, such as patients with chorea (a movement disorder) not perceiving their limbs are moving when in reality their limbs move around in wild patterns in a continuous manner, and in motor activities such as automatic responses to tasks, sleepwalking, and neurological disorders like alien hand syndrome, where after damage to certain parts of the motor control area of the brain, patients limbs can move, but the patients do not feel they have control or agency over these movements, and that the limbs are moving as if controlled by ‘another’.

If our movements and actions are not controlled consciously or in a free willed way, where and how does the control of movement occur? Of course to answer this brings in the notion of the unconscious, and that control mechanisms occur in some manner and in some brain structures that occur automatically at a level which is ‘not available to introspection’ (if they were we would be consciously aware of this), which to most scientists is problematic given that such a concept would therefore be impossible to understand with the research techniques we currently have available. The concept of the unconscious is also unfortunately a controversial one for ‘political’ / moral reasons, because it is related to the work and ideas of Sigmund Freud, who suggested that unconscious sexual urges, and the gratification of these, was the basis of all planned human movement and actions. These suggestions perhaps unsurprisingly generated abhorrence for his theories from both colleagues and society after they were published, although the unconscious was described and discussed as a concept long before Freud theorized about its actions and existence. Unconscious processes such as memory storage and automated movement are routinely accepted as fact, but when intent, agency, motivation, phobias, complexes and desires are discussed, controversy rages regarding whether these do exist at an unconscious level, or are purely conscious entities. Libet’s study was the first objective study which showed that, at least from a physical / electrical brain activity perspective, action was indeed controlled by these unconscious processes, which were for so long theorized about, yet were essentially unproven until his seminal work.

So going back to the popcorn episode in my case, and that of the peanuts in Mark Hallett’s article, it would appear from Libet’s experiment that Mark and I, and surely all folk, are not completely ‘in control’ of our actions as much as we would like to be. While this is a worrying concept if one believes in free will, and that we are masters of our own destiny from a conscious, ‘choice’ perspective, it is helpful to all folk in explaining why one does things that seem contrary to what ones conscious wishes, or occasionally moral wishes, are. There clearly is an ‘agency’ that ‘drives’ what we do and what we want (dare I say desire), that occurs at an unconscious / subliminal level, and which often appears to create discordancy with our conscious desires and wishes. We currently have no idea where in the brain this unconscious ‘agency’ exists or how it ‘works’ – psychologists use dream assessment as one technique of understanding them, and neurophysiologists techniques like galvanic skin responses to psychological suggestion (saying something to a person which might make them feel uncomfortable, and monitoring their skin conductance changes as a measure of their discomfort – similar to what happens in a lie detector test), but these are all very nebulous measures of the function of unconscious processes. Perhaps even if we cannot at this point understand ‘where’ or ‘how’ unconscious agency occurs, an understanding that it surely exists in all of us, and that free will may be an illusion created by it, is helpful at least in assuaging the guilt most of us feel when ‘succumbing’ to our ‘desires’, such as those that I felt for the popcorn this week that lead to my hand reaching out for more almost ‘without control’. Of course most folk perceive that the danger exists, when accepting a potential lack of conscious control as part of our routine existence, of losing the capacity for ‘self-discipline’ and our life sustaining healthy habits and social structures, if we ‘agree’ to use this information as an ‘excuse’ to not worry about succumbing to each of our unconscious desires. However, whether one worries or not appears to not make make much difference to the actions of our unconscious agency, and the question perhaps should be why there is so often a ‘dissonance’ between what our conscious thoughts ‘tell us’ we should want or what we should do (or more often not do!), and what our unconscious agency insists on, as in the case of the popcorn incident. The concept of a lack of free will is also of course troubling to our sense of self identity, and the confidence we feel as a result of perceiving we are in control of most situations and our own destiny, at least on a personal level. As Freud put it, there have been three severe ‘blows’ dealt to human vanity by science (as Paul Ferris well described in his biography of Freud) – the first ‘blow’ being the cosmological one, which removed humans from their perceived position as the centre of the / their universe; the second being the biological one, when Darwin’s work showed our animal origins; and the third, and in Freud’s words, the ‘most wounding’, being the psychological, which ‘rearranged the mind to make it subject to a dilatory unconscious, and so demonstrated that the ego is not master in its own house’. The classic study performed by Libet was the first objective study to give us evidence that Freud may have indeed have been right about the third ‘blow’, or at least about the presence of unconscious agency. So I guess that at least until scientist folk work out how unconscious agency works, and I can perhaps better control and prevent my hand from reaching out for it after the scientists work out its mechanism of action, the only solution to the popcorn issue is in future to please hide that bowl of popcorn from me in order to protect me from my own unconscious drives!


About Alan (Zig) St Clair Gibson

Professor Alan (Zig) St Clair Gibson MBChB PhD MD - Deputy Dean (Research), Faculty of Science and Health, University of Essex, Colchester, United Kingdom View all posts by Alan (Zig) St Clair Gibson

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