The Self Illusion

by Bruce Hood

  The pessimistic view of determinism is also unwarranted because we simply wouldn’t be able to comprehend the patterns of causality in any meaningful way. Aside from very simple actions that we consider next, the complexity of the underlying processes that make up our mental lives is going to be one that proves impossible to predict with any degree of certainty – it might as well be random and undecided. It’s like watching a soccer match. We appreciate that the laws of physics govern the movement of the players and ball but that does not mean you can predict with any certainty how the moves in the game will play out. At best, we may be able to get close to figuring out what will happen, but to use a term borrowed from engineering, there are simply too many degrees of freedom to make an accurate prediction of what the system will do. The problem of too many degrees of freedom means that, every time you add another factor that can exert an influence on your decision-making, you change the predictability of a system.

  Let’s consider some numbers again. With just 500 neurons, the number of possible different patterns of connections you could have exceeds the estimated total number of atoms in the observable universe. With billions of neurons, each with up to 10,000 connections, that suggests an almost infinite number of possible brain states. So figuring out what each pattern of electrical activity does is simply not feasible. The other problem is that no two brains are identical. Even identical clones of a very simple organism such as the water flea, when raised in the same environment have different patterns of neural connections.7 So any mapping of one brain is not going to apply directly to that of another.

  A final nail in the coffin of predictable determinism is that thousands of different brain states can produce the same output. This is known in philosophy as ‘multiple realizability’,8 although I prefer the more familiar phrase, ‘There is more than one way to skin a cat’! What this means simply is that many different patterns of brain activity can produce the same thoughts and behaviours. There is no unique one-to-one mapping between the brain’s activities and the output of the individual. For example, scientists looked at a much simpler nervous system than the human brain – the gut of a lobster – and carefully recorded as many different patterns of activity of the nerves that control the digestive movements. They found that thousands of different patterns produced the same behaviour.9 For any individual cell, there were multiple patterns of activity with other connecting cells that produced the same output.

  Multiple realizability is likely to be true for the human brain as well. In other words, our thoughts and behaviours are realized in multiple pathways of activity, which is a good thing. Remember that the neural networks are massively parallel. This means that the same neurons can be triggered by a variety of spreading activations. This parallel structure explains the speed, the complexity and ultimately the richness of mental life but it also means that you are never going to be able to map it out precisely – even within the same individual brain,

  Despite the complexity of the mathematics of brain activity, many are still deeply unsatisfied with a materialist account of the mind, even if it is not predictable. We want to believe that we are more than fleshy computing devices that have evolved to replicate. We are not simply meat machines. Maybe there is some as yet undiscovered force at work? After all, we are continually reminded that most of the universe is made up of stuff that we know is there but cannot measure. How can scientists rule out the non-material explanation for the mind and free will if they themselves admit that they do not know everything?

  The answer is they can’t. Science can only investigate and evaluate different models of the world and those models are only going to be approximations of the true state of the universe – which, frankly, we may never know. But science is continually moving forward and progressing by refining the models to better fit the evidence. And the evidence comes from our observations. However, sometimes observations are wrong. The big trouble with free will is that it just feels so real. All of us think that our thoughts happen in advance of what we do. Time moves forward and we experience that our thoughts cause actions. It turns out that this is wrong and we know this from the simple press of a button.

  Living in the Past

  Imagine I ask you to push a button whenever you feel like it. Just wait until you feel good and ready. In other words, the choice of when you want to do it is entirely up to you. After some time you make the decision that you are going to push the button, and low and behold you do so. What could be more obvious as an example of free will? Nothing – except that you have just experienced one of the most compelling and bizarre illusions of the human mind.

  In the 1980s, Californian physiologist Benjamin Libet was working on the neural impulses that generate movements and motor acts. Prior to most voluntary motor acts such as pushing a button with a finger, there is a spike of neural activity in the brain’s motor cortex region that is responsible for producing the eventual movement of the finger. This is known as the ‘readiness potential’ (RP) and it is the forerunner to the cascade of brain activation that actually makes the finger move. Of course, in making a decision, we also experience a conscious intention or free will to initiate the act of pushing the button about a fifth of a second before we actually begin to press the button. But here’s the spooky thing. Libet demonstrated that there was a mismatch between when the readiness potential began and the point when the individual experienced the conscious intention to push the button.10

  By having adults watch a clock with a moving dot that made a full rotation every 2.65 seconds, Libet established that adults felt the urge to push the button a full half second after the readiness potential had already been triggered. In other words, the brain activity was already preparing to press the button before the subject was aware of their own conscious decision. This interval was at least twice as long as the time between consciously deciding to push the button and the actual movement of the finger. This means that when we think that we are consciously making a decision, it has already happened unconsciously. In effect, our consciousness is living in the past.

  One might argue that half a second is hardly a long time but, more recently, researchers using brain imaging have been able to push this boundary back to seven seconds.11 They can predict on the basis of brain activity which of two buttons a subject will eventually press. This is shocking. As you can imagine, these sorts of findings create havoc for most people. How can we be so out of touch with our bodies? Do we have no conscious control? The whole point about voluntary acts is that we feel both the intention to act and the effort of our agency. We feel there is a moment in time when we have decided to do something, which is followed by the execution of the act. Brain science tells us that in these experiments, the feeling of intention occurs after the fact.

  However, Libet’s findings do not mean that intention cannot precede actions. We can all plan for the future and it would be ludicrous to say otherwise. For example, in the morning I made the decision to check the mailbox, at the end of the drive, in the afternoon, and I did just that – I made a plan of action and then enacted it. There was no readiness potential in my brain to visit the mailbox. Likewise, many other actions happen without conscious deliberation and thank goodness for that. Imagine if you had to think about jamming on the brakes in a vehicle pile-up: you would be a goner. Whether it is long-term goals or automatic behaviours triggered by external events, in both instances the experience of intention happens either well in advance or sometimes not all. Our actions don’t always follow our intentions as in the Libet demonstration.

  What Libet’s findings really show is that in a situation where we are asked to both initiate a willed action and monitor when we think we have initiated the action, the preparation for the movement happens well before we become aware of our intention. Most people find this amazing. However, neuroscientists are less impressed because they know the brain generates both the movement and conscious awareness. This makes impartiality and objective evaluation impossible. Another problem fo
r interpreting the time-course of events is that the brain activation that generates conscious awareness is not a single point in time but rather is distributed. In other words, although we can suddenly become aware of an instance when we have made a decision, that process must have been building up for some period. It may feel like it happened spontaneously just before we moved our finger, but it didn’t. We just thought so. Spinoza figured this out 350 years ago.

  One big misinterpretation of Libet’s findings, and of appreciating the true nature of the self in general, is that one cannot passively wait for an urge to occur while at the same time monitoring when one becomes conscious of bringing it about. We cannot step outside of our mind and say, ‘Yes, that’s when I felt the urge to move, and that’s when I actually started to do so.’ You cannot have your mental cake and eat it. As the philosopher Gilbert Ryle12 pointed out, in searching for the self, one cannot simultaneously be the hunter and the hunted. Such reasoning reflects our inherent dualist belief that our mind is separate from our body.

  We may think that our mind controls our body but that is an illusion of free will and control. This illusion arises when our subjective conscious intention precedes the actual execution of the movement with little delay. We know this timing is critical because, if you disrupt the link between when you experience the intention to act and the execution of the act, we experience a loss of willed action. This is when we feel that we are not in control of our bodies.

  Being in Two Minds

  Most of the time we feel we have control over our actions. There are exceptions such as reflexes that do not involve conscious control and, as discussed, some behaviours are surprisingly infectious such as laughing and yawning when in a crowd, but for the most part our normal daily actions seem under our control. However, brain damage can change all of that. When we damage our brain, we can lose control over our bodies. Paralysis is the most common example. Our limbs may be perfectly fine but if we damage the brain centres for movement then, irrespective of our strongest will, our paralysed limbs cannot move. Sometimes, though, parts of our body can move by themselves. For example, ‘alien hand syndrome’ is a condition in which patients are not in control of one of their hands and experience the actions as controlled by someone else or that the hand has a will of its own.13 This is also known as the ‘Dr Strangelove syndrome’, a nod to Stanley Kubrick’s 1964 movie in which Peter Sellers plays a wheelchair-bound nuclear war expert and former Nazi whose uncontrollable hand makes Nazi salutes and attempts to strangle him. Strange as Dr Strangelove syndrome might seem, there is a perfectly reasonable explanation based on the discovery that each hand is under relatively independent control from the opposite side of the brain.

  For reasons that Mother Nature knows best, much of processing and output in the brain is lateralized to the opposite hemisphere. If you were to draw an imaginary line down the centre of the human body then all the information coming from the left side of the world goes to the right hemisphere. Likewise, all the information from the right side is processed in the left hemisphere. The same is true for actions. The left hemisphere controls the right side of the body and the right hemisphere controls the left. If you severely damage the left hemisphere then you can be left paralysed down the right side of the body and vice versa.

  Some skills tend to be lateralized. For example, the left hemisphere controls language whereas the right hemisphere is better at the visual processing of the space around us. That’s why brain damage to the left hemisphere disrupts language and patients become aphasic (unable to produce speech) whereas damage to the right hemisphere leaves language intact but often disrupts the patient’s awareness of objects especially if they are in the left side of space.

  We are not aware of these divisions of labour as the two hemispheres work together to produce joined-up thoughts and behaviours. This is because the two sides of the brain are connected together through the large bundle of fibres of the corpus callosum that enables the exchange of information. This exchange also enables the abnormal electrical activity of epilepsy, which can originate in one hemisphere, and spread to both sides of the brain causing major seizures. Epilepsy can be extremely debilitating but by severing the corpus callosum fibres that connect the two hemispheres, the electrical brainstorm can be contained and prevented from transferring from the original site to the rest of the brain. This containment alleviates the worst of the symptoms.

  The consequence of this operation is to produce a ‘split brain’ patient. The two halves of the brain continue to work independently of each other but you would be hard pressed to notice any difference. Spilt-brain patients look and behave perfectly normally. This begs the question of why we need the two halves of the brain connected in the first place. In fact, it turns out that split-brain patients are not normal. They are just very good at compensating for the loss of the exchange of brain activity that is normally passed backwards and forwards between the two hemispheres of the intact brain.

  Neuroscientist Michael Gazzaniga has shown that these split-brain patients can effectively have each half of the body thinking and acting in a different way. One of his most dramatic observations sounds very similar to the Dr Strangelove syndrome.14 He gave one of his split-brain patients a puzzle to solve using only his right hand (controlled by the language-dominate left hemisphere). However, this was a spatial puzzle in which where the blocks had to be put in the correct position (something that requires the activity of the right hemisphere). The right hand was hopeless, turning the blocks over and over until, as if frustrated, the left hand, which the patient had been sitting on, jumped in and tried to take the blocks away from the patient’s right hand. It was if the hand had a different personality.

  Sometimes this lack of control takes over the whole body. French neurologist François Lhermitte reported a bizarre condition that he called ‘environmental dependency syndrome’ in which patients slavishly copied the doctor’s behaviour.15 Like the Tourette’s patient who had to mimic every other person’s behaviour, Lhermitte’s patients were similarly compelled to copy every action the doctor made. At one point, the French neurologist got down on his knees in his office as if to pray, whereupon the patient copied him with her head bowed and hands clasped in prayer. Other patients exhibited a related behaviour known as ‘utilization’ in which the sight of an object triggered an involuntary associated response.16 Such patients will pick up cups in their vicinity and start drinking from them, even when the cup is empty or not theirs. They will feel the compulsion to flick light switches and pull handles. In all of these examples, the patients’ actions are triggered by external events and not their own voluntary action, although some may reinterpret their unusual behaviour as if it arose of their own free will. They will justify their actions as if they willed them when, in fact, it was something in the environment that had taken control over their actions.

  ‘The Great Selfini’

  When not bedevilled by strange neurological disorders, most of us feel we are in control because the coupling between the mental state of consciousness and initiated actions in everyday experience confirms our belief that we have willed our actions freely and in advance of their initiation. But if the reality of free will is an illusion, then why do we experience it so strongly? Why do we need the experience of free will? Why did it evolve?

  Harvard psychologist Dan Wegner has written one of the best accounts of why we evolved the vivid experience of free will.17 Wegner argues that we have a brain that interprets actions in terms of a ‘we think we did it’ experience as a very useful way of keeping track of our decisions and actions. This is because the multiple conscious or unconscious influences and processes that lead to these choices are too complicated or hidden to monitor, but we can keep track of the outcome as a feeling that we have made the decision. For example, we may be at a party and want to impress some of the guests. Think of all the reasons why we might feel the need to do this – social anxiety, fear of rejection, the need to be at the centre of attent
ion and so on. What do we do? We rely on our experience of past situations to come up with a strategy: we decide to tell a joke. We monitor the outcome and then store this for reference for future parties. We told a joke but were we free to do otherwise? Of course, we feel we made the decision but there were a multitude of previous experiences as well as current social norms and rules that influenced our choice. When our behaviours go wrong or we make a faux pas, we feel self-conscious and embarrassed and privately ask our selves, ‘What was I thinking?’

  Having an experience of free will over our thoughts and actions binds us to these as the instigator of these decisions, even when that may not be the case. In this way, a sense of free will could help us keep track of what we have done, what we have not done and what we may, or may not, do in the future. As long as our conscious intention appears to precede our actions, then it is natural to assume that we willed them.

  This authorship of actions requires the illusion of a unified sense of self. After all, it is useful to know who is responsible. Wegner18 has called this master illusionist ‘The Great Selfini’. As we act on the world, we interpret the consequences of actions from the privileged prospective of our singular self. This has some interesting consequences. For example, we remember our actions much better than those belonging to others. Whether the actions are walking, throwing darts or clapping hands, people are better at recognizing their own movements compared to those of others. In fact, we seem to be biased to remember those that pertain to us simply by acting on the world. In one study,19 individuals either selected slips of paper from a bowl or had them handed to them by the experimenter. The experimenter then read out the words associated with the code on each slip. In comparison to those individuals who had the slip given to them, those who chose their own slip remembered more of the words, even though they were never aware of the purpose of the study. It was a consequence of inconsequential actions, but because most of us are trip-wired to pay attention to our self, we tend to give special effort to anything we do.