Episode Four: The Consciousness Problem

This is the episode I have been most dreading. I’ve tried to keep these podcasts simple and easy to understand without dumbing down too much, but consciousness is such an expansive and involved topic this will be hard to do in a single podcast episode. And, spoiler alert here, this episode will not explain consciousness. Many far more capable and learned minds than mine have applied themselves to this problem and the consensus of current opinion is that they failed to do so. 

Here is a short quote from philosopher A. C. Grayling’s 2021 book, “The Frontiers of Knowledge,” which spells out the problem more eloquently than I can:

“It [consciousness] is simultaneously the most familiar and the most mysterious thing in the universe. It is the most familiar because we experience it, intimately and immediately, in all our waking moments and, in somewhat stranger forms, many sleeping ones. We also feel its distortions when drunk or drugged, or infatuated. We therefore know what it feels like to be conscious pretty well.

It is the most mysterious, because we have little idea of what it is, and no idea of how it arises from brain activity – some will add: if it does so.” End of quote.

So, in this episode my role is also to fail to explain consciousness, but to do so as informatively, and with as much skill and aplomb as I can muster. In Episode One, I said that in the journey of understanding on which we are embarked, the path fades at one point. This is that point. As Grayling illustrates, there is a problem, what neuroscientists and psychologists call the Hard Problem of Consciousness, first labelled as such by philosopher, David Chalmers, in 1994 and it is the question of how a physical object, the brain, can produce a mental one: that rich and extraordinary experience of being alive we call consciousness.

Before this episode in this series, I have steered away from talking about consciousness; awareness is a much simpler concept. So how does, what I’ve called awareness relate to consciousness? And what do we know about how brains do it? Rene Descartes, the “I think therefore I am” philosopher we met in Episode One, thought that mind and matter were two completely separate things. This idea is unpopular today for the very good reason that I just raised my arm. Did you see that? Of course you didn’t this is a podcast. But if I decided to raise my arm in my mind then my physical arm does rise it means that mind and matter cannot be two separate things.

One way of thinking about consciousness is to say that the brain is like a wire, and the mind is like the flow of electrons: the electricity that goes through it. On this view the brain is made up of particles while the mind is the movement of some of those particles. Another way of thinking about it is that brains are like computer hardware while minds are the software. The computer scientist, Marvin Minsky, said: “The mind is what the brain does”. But none of these comparisons gets us very far. While the brain’s neurons communicate with each other and do so in an almost infinitely complex way, on the face of it, this does not seem to be that much different to the mechanistic process of wires connecting in an electric circuit. It might be argued – and it is by some – that computers have something like consciousness. They make decisions based on inputs just like the brain does.

This argument seems to be that consciousness emerges spontaneously, simply on account of the vast amount of complexity, and the intricately, involved computations, that go on inside advanced brains like ours, so that, if this were true, if we built a computer big and complex enough it would be conscious like a human being. Hmm. I’m not sure that this amounts to the kind of awareness of feeling that we are looking for if we want to explain Nova’s experience of crossing the Awareness Horizon. Perhaps the answer is that we experience qualitatively different experiences when different neural circuits are energised. When one circuit is activated, we might feel hate, when another one fires up, we might feel love. More of the same circuits on their own can’t be the sole answer; something must be different about the two circuits if they produce different experiences. Just adding more wires and transistors into the mix doesn’t seem to get us an answer to the conundrum. This just gets worse when we come to specific kinds of experiences like, for example experiencing the colour red. What is going on in the brain that is different when we experience red compared to when we are experiencing blue, for example. Scientists and philosophers call experiences like seeing colours qualia.

Some thinkers, such as Daniel Dennett are sceptical about the importance of qualia. Remember him, the guy who wrote Darwin’s Dangerous idea? Dennett does not, of course, deny that people do experience red and blue sensations, but he doesn’t think we need anything more than the explanations we already have, to explain the mind. He thinks that what happens in the brain just creates a “mirage” that we experience as a mind. I agree that best guess reasoning does not seem to point to spooky outside influence and the brain and other parts of our nervous systems must be solely responsible for producing consciousness. Dennett’s demystification of the process is welcome when there are people who think that consciousness is beyond explanation or that it somehow connects us to some outer non-rational or non-physical explanation. But I think we still need to know more about how brains do it.

What do we know about brains that might help? Well actually quite a lot. The computational aspects of the way the brain reasons and works things out, as opposed to the emotional aspects of consciousness, are now very well understood.

When different parts of the brain become damaged due to injury or illness it has been possible to work out what parts of the brain do what. We also have a wide range of machines like fMRI, EEG and PET scanners so we can find out what parts of the brain are active at any specific moment, so we know how brains are behaving when the subjects of experiments are experiencing different things. 

Let’s describe the overall structure of a typical human brain. When you look at pictures of the outside of the brain you can see that wrinkly pinky, purply, reddish surface. This is called the cerebral cortex, and neuroscientists think of it as being divided into lobes. The one at the back of the brain is called the occipital lobe; it’s where the optic nerves terminate. This lobe is involved in sorting and interpreting the vast amounts of data coming from the eyes, so it is principally concerned with vision, which might present itself to you and me as a simple process, but it actually involves a massively complex series of procedures that take place in different parts of the brain: there are at least ten neural pathways that come from the eyes into the brain. Across the top of the brain, in what’s called the parietal lobe, there is a region called the Penfield Homunculus. Because the brain doesn’t have nerve endings and you cannot feel pain there, there are surgical procedures that allow the skull to be opened in living conscious patients, and when different parts of this region are stimulated with a mild electric shock, it has been found that the patient feels sensations in different parts of the body, so astonishingly, it is as if there is a map of your body printed across this part of the surface of your brain. 

On either side of the brain are the temporal lobes. On the left side there are regions that are responsible for creating and understanding speech. Some people that have epilepsy in another part of their left temporal lobe have profoundly powerful experiences which feel to them like religious or spiritual revelation. The frontal lobes, which are found behind your forehead, are involved in inhibiting more basic emotional responses. When psychopaths have their brains scanned, it has been found that this region of their brains is much less active than in people without the condition, so they can’t seem to moderate their behaviour in the way most people can. Of course, some, though far from all, psychopaths are known to be serial killers.

Of perhaps more interest to us in explaining Nova’s awareness are more ancient structures that are found deeper within the brain under the cerebral cortex. First there is the limbic system. Here there are parts of the brain involved in emotion, the laying down of new memory and olfaction – the sense of smell. A structure called the amygdala lights up when its owner is experiencing fear. The hypothalamus is involved in regulating hormonal activity in the body and the hippocampus helps to create new memories. Beneath the limbic system there are even more ancient systems: In a part called the forebrain, the striatum is involved in feelings about something being good or bad and then there is the hindbrain, which includes another large part of the brain called the cerebellum which is tucked under the occipital lobes at the back of the brain, and is known mainly to be responsible for co-ordination, balance and body posture. The cerebellum, interestingly, has as many neurons as the rest of the brain put together, but there is some doubt about whether it has a role in conscious processing.

Beneath these structures is the brain stem. This is where the spinal cord enters the brain, and it is involved in homeostasis: that’s basic bodily functions like breathing and thermoregulation.

There appears to be no individual region of the brain responsible for consciousness. All parts of the brain are connected up in different ways, so that for example seeing a vicious dog ready to attack you would involve neural activity in the occipital lobes, and related areas, where messages from the eyes would be decoded so that you experience an image of the dog, memory circuits would be involved so you could identify the dog, as, well, a dog. Other cognitive circuitry would become active to evaluate the threat – it’s a dangerous dog – signals would also go to the amygdala which would light up generating a sensation of fear. Other signals would be sent from the hypothalamus to the adrenal gland flooding the body with adrenalin making it ready for immediate action, the frontal lobes would make the decision about whether to run like hell, or to stand your ground and move back slowly and it would send messages to the parietal lobe to tell the body how to proceed. 

As humans, we think it is just the conscious me that makes the decisions, but this doesn’t seem to work quite in the way you might think. Most mental processing actually happens without the me being aware of it. But it does seem to be true that any conscious experience involves more than one part of the brain. The brain does not have a consciousness centre.

If all this sounds complicated, I haven’t started yet. The neurons in the brain have evolved to respond to chemicals called neurotransmitters. Some of these are released from a fountain-like array of chemical releasing neurons that radiate out from the centre of the brain. When these chemicals are released, they trigger particular responses. When you get a flush of excitement, this is caused by the release of a chemical called dopamine, a sense of achievement, and euphoria from one called serotonin. And the “cuddle” hormone oxytocin is released when you hug someone you care about. Neurons in different parts of the brain have receptors that respond to the chemicals, influencing the way they send signals to other neurons. But studies of brain anatomy and chemistry combined with clinical investigations and brain scans can only get us so far in understanding consciousness. One possible answer is that we may need to know is what is going on at a more fundamental level: what is happening inside the neuron itself that makes it different from a simple current going through a wire, and science can only give a partial answer to this question. We do know a lot about how the brain wires itself up during development and how it reorganises itself in response to new learning experiences. In this sense the brain is said to be “plastic” because it can readily rewire itself to cope with the changing threats and opportunities in the world outside. Neurons are not all the same, there are a huge variety of shapes and sizes. To send a signal neurons fire in what is called an action potential, and the wave frequency in which they fire can vary enormously from one or two times a second up to five hundred times a second, and the amplitude ­– the size of the wave – varies too. So, until we fully understand what these complex cells are doing, we may not be anywhere near the end of understanding how feeling is generated.

One idea about how consciousness emerges suggests that there might be communication going on in the brain at an even smaller scale. It has been proposed by Roger Penrose and Stuart Hameroff that quantum effects might have a role to play in the way consciousness works. Quantum mechanics works at the level of sub-atomic particles, but that doesn’t mean quantum effects can’t carry across large distances. The idea here seems to be that: say you are looking for your keys. You know they are in the drawer, and you are looking into it, but there is an untidy mess of lots of other similar objects, scissors, candles, a torch, ball of string and so on. Then, in a eureka moment, you spot your keys. “There they are!” This is where it all gets a bit strange – quantum physics is like that – but what these investigators think might be happening is that at the moment of revelation when you “see” your keys, particles in different parts of the brain collapse into a special kind of relationship called quantum entanglement. The part of the brain that can see but not recognise the keys suddenly connects with the part of the brain that has the capacity to remember what keys are and can identify them. If this theory is correct then different parts of the brain can communicate with each other in ways in which, before we knew about quantum mechanics, we could never have guessed. To illustrate just how odd quantum theory is, as I understand it, we can think of entangled particles as being the same particle existing in two places at the same time. Told you it was strange! Penrose does not appear, however, to think that quantum mechanics is the complete answer to the problem of consciousness, and it has to be said that, what seems to be, a majority of scientists, don’t think that quantum effects could work as he suggests. As someone from the outside looking in, I’m not qualified to comment on who’s right or wrong about this. 

Other neuroscientists think that connections between different parts of the brain, could have something to do with activity at a larger scale. When neurons fire they create a tiny electrical field, when lots of neurons fire together this field is amplified.  Sometimes this firing is synchronised across wide areas of the brain, and we get waves that are detectable in electro-encephalograph scanners. The idea here is that the sudden mental connection we experience as “seeing” those keys in the drawer, occurs when two brain regions synchronise the firing of their neurons. Some neuroscientists even seem to suggest that consciousness just is this field, and as philosopher Peter Godfrey-Smith thinks about it, the field can be “perturbed” by sensory inputs and emotional responses. But as important as this research is, I’m not sure it gets us nearer to the most important question from our point of view: that is understanding how feelings are produced

Perhaps part of the problem is that there has been a historical reluctance to consider the question of feeling in the male-dominated scientific and philosophical communities. Although this situation seems to have been changing more recently, this is what the neuroscientist, Susan Greenfield wrote in her book, “The Private Life of the Brain” in 2000: 

Quote, “…I am suggesting that some sort of basic emotional state is present whenever you are conscious. And if emotion is a phenomenon that is inextricable from consciousness itself, then it should be a high priority for neuroscientists. Yet surprisingly, emotions have to date received relatively scant attention.”  End of quote.

Scientists at the time obviously had not had the opportunity to listen to Episode Three of this series.

Perhaps before we ask what consciousness is, we first need to explain awareness. What’s the difference?  Well, by awareness I mean any sensation made up of feeling, and maybe sensations like experiencing blueness or redness are special kinds of feeling. Explaining awareness is all important. The reason I didn’t call the Awareness Horizon, the Consciousness Horizon, is because I didn’t want to suggest that Nova would have had full consciousness in the way that we humans do. While mental activities like willings, urges, beliefs and emotion are obviously underpinned by feeling, consciousness seems to be more than just awareness of these phenomena. For example, I can look at the wall in front of me, and know it is there without any obvious emotional content in my mind. The input here is sensory rather than being rooted in feeling. If we could explain the simple awareness of feeling, and sensory input, and we accept that consciousness amounts to lots of different kinds of awarenesses experienced either sequentially or simultaneously, in different parts of the brain, the Hard Problem looks much less intractable. 

If the idea that consciousness is an electromagnetic field “perturbed” by outside influence is the right one, it raises the possibility that the simple awareness that Nova felt might have just been the acquisition of just enough neurons firing in sequence to produce a particular kind of electro-magnetic field, or, if the explanation for awareness can be found at the smaller level: it could have been a genetic mutation that changed the neurons themselves. 

The more difficult question of consciousness could then be explained as a whole load of awarenesses, created by effects at the small scale, or the larger one, or some combination of the two, except of course this creates two more problems, we still don’t know what is different about one neural circuit that generates a feeling of love, and another that produces a feeling of hate, or the sensation of blue as opposed to red? What could be different about them? And the second is another hard problem: the problem of how a set of interconnected neurons creates feeling in the first place. So even if we accept that the real Hard Problem is explaining the generation of sensory experience and feeling, we haven’t solved the problem at all, we have deferred it: just pushed it back a bit.

With or without a focus on emotion, the Hard Problem is still a hard problem. But is this the right way to think about it? Are we even asking the right question? Maybe this is where the human intuition problem raises its ugly head again. Maybe we are designed to think consciousness is a lot more special and difficult to explain than it really is. Whether or not this is part of the answer. I suspect that this might be an idea to which Daniel Dennett might be sympathetic.

Looking at this from the outside and in the context of evolutionary ways of thinking. Perhaps we could think of awareness as being an excited state in some part of Nova’s primitive brain. Many physical processes involve excitement. A hot water bottle is warm because the water molecules in it have a certain level of energy causing them to jiggle about: that excited state is just what heat is. It would have been in Nova’s evolutionary interests for her to respond to, for example, threatening stimuli, with some kind of excitation in her nervous system, whether at the small or large scale, so it could trigger whatever physiological changes that needed to happen to cause her to move away from a potential threat more quickly than she would have done otherwise. The best, explanation we have for awareness, and therefore consciousness, is that feeling is just this excited state, and if that sounds like a weak answer, I’m not arguing, I just haven’t got a better one.

Without explaining the awareness of feeling, the theory I am developing in this series of podcasts is incomplete. I can’t claim to explain meaning in the universe via the concept of the Awareness Horizon if I can’t even explain what simple awareness amounts to. But incomplete theories can sometimes be hugely influential and important. When Darwin developed his theory of evolution by natural selection, there was a huge gap in his theory too. At that time no one knew about genes. What Darwin called “the laws of inheritance” were unknown, and he knew they were unknown. In order to fully understand what was going on it needed scientists to develop a whole new science, the science of genetics, which was eventually found to dovetail neatly into Darwin’s theory and made it an even more powerful one. And, as we saw in Episode Two, genetics was instrumental in refining and confirming his theory of evolution. 

In order to complete my theory, I freely admit that we may well need a new, or at least better, science of consciousness.

We started this episode with a quote from A C Grayling, perhaps we should end it with two others of his which I’ve kind of cobbled together from the same book, in a way which I think will best get his point across: quote “…even though there is nothing in the universe that is not ultimately a matter of physics, the brain is not the whole story of the mind “mind’ is not solely describable in terms of brain activity alone, but must be understood as a relationship between that activity and the social and physical environment external to it.” End of quote. Wise words, I think.

Here I need to thank Professor Fred Coolidge from the University of Colorado, for kindly agreeing to read through the script of this episode and making some useful comments. 

Phew! That’s the hardest of these episodes over. Thank goodness. Thanks for sticking with it and I’ll see you in the next episode.