Summary with Consciousness Blackmore & Troscianko - 3rd edition
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If you think back to the things you do and the movements you make, there is often a disconnect between the build up and the actual action. Think of it like waking up and it is freezing, but you are under the covers and there it’s warm.
The question James asks us in this scenario, is, how on earth do we get up, under these circumstances? Where does the will to get up and go about your day come from? It might involve a long process of convincing yourself of sticking a leg out of the covers, then removing them, then getting up, but other days, you blink, and you find that you miraculously just got up, without any conscious decision to do so. (Exercise 1) This is example of the oddity that is free will.
The problem of free will may be the most-discussed philosophical problem of all time and we can date is back to as far as the Ancient Greek philosophers two thousand years ago. The basic question is whether or not we are free to choose our actions and make decisions, and for us and this book, it is whether consciousness has any role to play in our acting freely or feeling the things we do.
Many religions bear the concept of free will, as well as the consequences of the actions that you make out of free will. Christianity has Heaven and Hell, in the Islam people are judged by the Almighty Allah. And when asked then what it is that made these choices, most religions point to the soul as the one with the free will. A form of consciousness then.
There are two main problems. For free will, the biggest problem is determinism: if this universe runs by deterministic laws, then everything that happens must be inevitable, so the argument goes, and if everything is inevitable, there is no room for free will. And without free will, there isn’t a point to doing anything, because there was no other way things could have gone.
The problem for the belief of absence of free will is moral responsibility: if I am not truly free to choose my actions, then how can I be held morally or legally responsible for them?
This is where the connections with self and consciousness come in. Because after all, we tend to believe that ‘I’ am the one who acts, the one who has free will. ‘I’ am the one who (un)consciously decided to spring out of bed early this morning. When the chosen action then happens, it seems as though my conscious thought was responsible.
And it’s true that it seems that without the conscious thought, you would not have done what you did, and that you consciously caused the action by deciding to do it. The question is: does consciousness really play a role in decision-making and choice? Is this sense of conscious agency justified or illusory? Chapter 8 tried to distinguish between conscious and unconscious, while this chapter will explore how consciousness relates more generally to our sense of personal agency and free will.
Remember the illusion? An illusion, if you think back to chapter 3, is not something that does not exist, but is something that is not what it seems.
So how does it seem to you? Does it seem as though you have free will, that your decisions are freely made by your conscious mind, even if that is only some of the time? If so, then ask yourself whether this could be an illusion. If it does not seem to you that your actions are initiated by conscious decisions, then seriously, why are you reading this book? (Aside of that it is required coursework, duh.)
Note that we are concerned here with consciousness. The question is not whether human beings are agents or can make choices. We may safely assume that they are and can. Unless you consider the option that none of this is real (brain-in-a-vat scenario, look it up), which we will put aside as an discussion for another day, I think you can speak of your own experience that you make choices and perform actions Humans are living biological creatures that survive, like all other creatures, by having boundaries between themselves and the outside world, and by taking control over certain aspects of that world. They respond to events, make plans and courses of action, and act accordingly, at least when not restrained or coerced. We can be just as sure that we think or feel things. So how does this create free will?
It would seem like consciousness is the cause of voluntary action, but when we look inside the brain, we see lots of areas involved in carrying out the different phases of a voluntary action. An obvious question to ask is where, if anywhere, does consciousness come in?
There are different pathways in the brain for externally and internally triggered actions (i.e. reaching up to catch a ball tossed at your head, or leaning in to kiss someone, though I suppose you could also argue that is externally triggered).
But some people, usually with malfunctional or injured brains, might experience something like involuntary actions. Varying from Tourette’s syndrome to people’s left arm that seems to have an entire will of it’s own, it’s hard to say that consciousness is what causes the body to act solely.
You are probably familiar with gratification choices, or choice in general. 45 cents not or a fifty-fifty chance of a euro later. Or more practically, do you wait until flight tickets get cheaper but risk them selling out? These are the kinds of situations found in neuroeconomics, the study of the brain bases of economic behaviour, and it turns out the brain turns to the most economically beneficial choice.
Even unconscious motivations can be measured. In one experiment, participants saw either a pound coin or a penny coin, and the force they exerted by gripping a handle determined how much they would get. They pressed harder for a share of the pound even when it was presented subliminally. Neuroimaging showed effects in part of the basal forebrain. This suggests the perhaps slightly worrying idea that unnoticed stimuli around you are constantly affecting your motivations, and you are consciously less in control then you might think.
Ever had you decided you were going to eat healthy this week and yet found yourself reaching for a chocolate chip cookie? Then, two millimetres away from it, you stop yourself. Why did you suddenly stop? Decisions like this require what we think of as self-control to choose the option that is better in the long run over one which is immediately tempting. In one study of dieters making decisions about what to eat, fMRI scans suggested that the ventromedial prefrontal cortex was involved in encoding goal values, while activity in the DLPFC modulated these value signals when the participants were exercising self-control. Cool huh?
But all these experiments all come down to the following; the real problem for our purposes here is not just that isolating the neural correlates of ‘free will itself’ is fiendishly hard. It is the problem we keep coming up against in different guises: that having motivations and making decisions doesn’t feel like it’s just neurons firing. It feels as though there is something else – me, my own mind, my consciousness – that makes me free to act the way I want. (Honestly, for as against as this book seems when it comes to dualism, there is a lot of dualistic imagery.)
One of the most important questions to ask when it comes to the relationship between consciousness and voluntary action is about the timing of the action. Does consciousness come early enough in the sequence of physical events that leads to an action to be able to exert a causal effect of its own? Or are we just conscious of the actions we take, without it influencing said action?
Benjamin Libet (he too is back guys!) did a series of experiments inspired by this question, which led to the conclusion that about half a second of continuous neuronal activity is required for consciousness. This became popularly known as Libet’s half-second delay.
He did plenty and varying experiments, and the result was that, under certain conditions, the patients reported the definite conscious sensation of being touched on the skin of the hand, even though the only touch was a brief train of stimulation to the brain. Using this method, Libet found a minimum intensity below which no sensation is produced no matter how long the stimulation continues. But the unexpected finding was that at this liminal intensity no experience was reported unless the stimulation continued for at least an average of 0.5 sec. At shorter durations, the intensity necessary for producing a reported experience rose very steeply. This length of time was roughly the same even when other variables, such as the frequency of pulses, were varied. The same was found in some subcortical pathways, but not in the dorsal columns of the spinal cord, on peripheral nerves, or on the skin. This is how the half-second delay came to be.
Libet concluded that ‘neuronal adequacy’ for conscious sensation is only achieved after half a second of continuous stimulation in somatosensory cortex. Obviously in ordinary life there is no direct stimulation of the brain by electrodes, but the implication would be that a sensory stimulus, whatever it may be, sets up continuing activity in somatosensory cortex and that this must continue for half a second if the stimulus is to be consciously perceived. On the surface, this conclusion seems very strange. Does it mean that consciousness takes half a second to build up? And does this imply that our conscious perceptions lag half a second behind the events of the real world, far too late to consciously exert free will in many rapidly evolving situations? Half a second is a very long time in brain terms. Signals travel along neurons at about 100 m per second and can take less than a millisecond to cross a synapse. A great deal can happen in half a second. This is true of behaviour as well. The reaction time to a simple stimulus (say pressing a button when a light comes on) can be as little as 200 ms, and recognising a stimulus takes more like 300–400 ms. Drivers can usually stop in response to a sudden danger in less than a second, and if we touch something dangerously hot our fingers will move out of the way in less than half a second. Could it really be that consciousness comes so much later than our actions?
It would imply that our behaviour in not ruled by our consciousness.
So if consciousness really takes half a second to build up, then it should be possible to touch someone on the skin and then block the sensation by stimulating the cortex up to half a second later. This was exactly what Libet found. He stimulated the skin first and then the cortex. When the cortical stimulus came between 200 and 500 ms after the skin stimulus, the skin stimulus was not consciously felt.
But then something strange happened. When testing, Libet found out that a sensation produced in the foot is always recognised earlier than a sensation stimulated in the brain, even when it came way later, which was a strange result.
Libet’s controversial suggestion was that sensory experiences are subjectively referred back in time once neuronal adequacy has been achieved. In other words, what happens with any sensation is this. Information travels from, say, the skin, up to the relevant sensory area of cortex. If, and only if, activity continues there for the requisite half a second, the stimulus is consciously perceived. At that point it is subjectively referred back to the actual time at which it happened. Kind of like sensory time travel, I suppose? If neuronal adequacy is not achieved (because the stimulus was not strong enough, because other brain processes suppressed the activity, or because a devious experimenter interfered directly in the cortex), nothing is consciously experienced.
So how do we judge these results, irregardless of Libet’s theory? In general, critics have not agreed on anything because there are quite some weaknesses in the methods and conditions of the experiments. The ideal way to be sure is to repeat the experiments, but medical advances mean that operations to expose the brain are now very rare and generally unethical. So the experiments are unlikely ever to be replicated. We are probably best, then, to assume that the findings are valid. The real controversy surrounds how to interpret them.
Libet’s own interpretation is his ‘time-on theory’ of consciousness. In his opinion, unconscious processes really do ‘become conscious’ when neuronal adequacy is achieved. He says that ‘when the duration of repetitive similar activations of appropriate neurons reaches a certain value, then the phenomenon of awareness emerges’. So again like an impulse threshold.
Libet seems to take a liking to controversial statements because he considered many more of these topics. In particular, he believes that the evidence for backwards referral raises problems for materialism and the theory of psychoneural identity (i.e. that consciousness and neural activity are the same thing). He even considers ‘the possibility that physical events are susceptible to an external “mental force” at the micro level, in a way that would not be observable or detectable’. So, in a way he employs a lot of dualism in his beliefs.
So, what it comes down to is that, by now, it is clear there is a separate system that functions before we are ever
9.1. Think back to the last thing you did, whether that’s picking up a coffee cup or tossing something in the trash. Did you consciously decide to do so? Or did you just think about maybe doing it and suddenly you were doing it? Or did you just do without even realising? What was the mental, conscious or unconscious build up to this action?
Summary of all chapters of Consciousness by Blackmore & Troscianko
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