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Tag Archives: mind
Around 2,200 years ago, Zhuangzi wondered whether he had dreamt he was a butterfly, or he was the butterfly dreaming he was Zhuangzi. About 1,800 years later, Descartes wondered whether he was dreaming even though he was under the impression that he was fully awake. What are dreams and what are the main philosophical worries associated with dreams and dreaming? In the next however many blog posts, I want to write about dreams and dreaming in a bid to shed some light on an area of enquiry that is often taken for granted, as well as hopefully saying something interesting about them in the process. This first post will be covering some of the preliminary science of sleep & dreaming as it’s almost impossible to really get to grips with some of the issues of dreaming (nowadays, anyway) without a basic understanding of how the brain works during sleep. If you’re already familiar with the following, then it’ll (hopefully!) serve as a refresher course, if you aren’t then I hope you don’t find it too taxing & enjoy finding out about one aspect of brain function. Onwards!
The Science Of Sleep
Scientific interest in dreaming has only really took off in the past 60 years ago, since the discovery of REM sleep in 1953 by Nathaniel Kleitman & Eugene Aserinsky (as is often noted in the literature, this was the same year Francis Crick & James Watson discovered the structure of the DNA molecule). In order to understand why the discovery of REM sleep is important for dream research, we’ll first need to understand the basic science of sleep as a whole.
We humans spend approximately 1/3 of our life sleeping and as you will already be aware, we are not the only animals to do so. In fact, the phenomena of sleep is almost universal across the entire animal kingdom (all mammals, all birds and some cold-blooded vertebrates sleep), but giving a universal definition of sleep is difficult because, given the huge variation & diversification across different species, there aren’t many traits we all have in common. Scientists use different aspects of sleep to identify which animals do sleep, or exhibit some behaviours associated with sleep (think of it as analogous to a family resemblance. Your family may not share one unique trait -such as a short nose, for example- but there may be several traits members of your family have some of, but you don’t all have the same ones -some might have the short nose, others the long chin, etc). For simplicity, we’ll stick with human sleep behaviour. Before I outline the various stages of sleep, I’ll need to quickly fill you in (assuming you don’t already know) about brain waves.
You probably know that there is quite a bit of electrical activity going on in the brain. One way of measuring this electrical activity is through the use of an EEG (ElectroEnthephalogram) machine. You’ll have probably seen these in the movies. Small metal disks are put on the subjects scalp which are wired to a machine which draws squiggly lines (in the older machines, paper would continually be fed through whilst a pen moved up and down depending on the electrical activity the disks picked up, more modern machines will do this digitally (click here for an example of an EEG readout)). Measuring this electrical activity is a measurement of brain waves. Awake as you are now, your brain waves will be very frequent (so, a measurement of how often they occur is a measurement of frequency), up to 15 every second, meaning that the neuronal firings will be in rapid succession. However, they are low voltage waves (which is measured by the amplitude -this is a measurement of the distance between the top & bottom of the wave). After an hour or so of being asleep your brain waves will be high amplitude but low frequency (this is stage 4 sleep, which I’ll get to in a bit), so the waves are high voltage but occurring less often.
Stages 1-4: NREM
Got all that? Good. Now, there are five stages of sleep which can be divided into two groups; REM & NREM sleep. There are four stages of NREM sleep and then the one stage of REM sleep. You will go through the four stages of NREM sleep (from stage 1 through to 4) and back again (from stage 4 back to stage 1) before you hit REM sleep.
When you’re getting sleepy, your brain moves from what is called beta activity (brain wave activity associated with being awake with a frequency between 15-30 Hz -Hertz, or Hz, is the standard unit of measurement for amplitude) to alpha activity (8-12 Hz). Anyone familiar with the Greek alphabet might note that this seems counterintuitive (beta is the second letter of the alphabet, alpha is the first), so you might not be too pleased to know that this odd use of the Greek alphabet just gets worse. When theta (eighth letter of the alphabet!) activity starts to show (registering a frequency of 3.5-7.5 Hz), this is an indication that the person has entered stage 1 of NREM sleep, though this stage is transitional between being awake and being asleep. At stage 2, sleep spindles will start to appear (short bursts of 12-16 Hz waves), and it is at this point that the person will become harder to wake. As you move through to stage 3 & 4 you start to get much more delta (fourth letter of the alphabet) activity (high amplitude waves occurring at less than 3.5 Hz). Aptly then, stages 3 & 4 are called slow-wave sleep. Stage 4 is reached in less than an hour but can last up to half an hour.
During stage 4 sleep (which is the deepest part of sleep), several things can happen (perhaps you’ve experienced them at some point during your life). Sleepwalking, which can range from just getting out of bed then climbing back in again to getting into one’s car (apparently, sleepwalkers don’t try to drive their cars). This is not thought to be the acting out of one’s dreams (for reasons we’ll get to later on). While sleepwalkers are difficult to wake up, contrary to popular belief it is completely safe to wake them; it won’t cause them any harm, though for obvious reasons they might be a bit confused! Sleeptalking is more likely to occur during NREM but not always. Night terrors or enursesis (bed wetting) can also occur. Night terrors are not to be confused with nightmares. Typically, night terrors are not preceded by bad dreams (or at any rate, bad dreams are rarely reported upon waking -again, we’ll come to why dreaming in general isn’t taken to occur in NREM sleep later), they are just the result of people (usually children) quickly waking from stage 4 sleep, screaming and frightened. The best treatment for night terrors is no treatment at all (it is not an indication of anything bad -the same advice goes for sleepwalking).
Stage 5: REM
Returning to our sleeping subject, the EEG machine will pick up the fact that after stage 4 they will start to regress, that is that they’ll start to move back through the NREM stages all the way to stage 1. However, their heartbeat will become irregular and their breathing will become shallow, occasionally gasping. If one were using an EOG (electrooculgram) machine (it monitors eye movement), you would notice the person’s eyes were darting rapidly around (up and down, side to side). Interestingly, the EEG readout will look like someone who is fully awake (high frequency, low amplitude waves). In fact, they are in REM sleep. The first episode of REM sleep will last around 20/30 minutes (after which they will repeat the NREM cycle). As each sleep cycle is completed, the period of REM sleep increases and the deeper stages of NREM tend to disappear. During an average 8 hour sleep, you will go through REM sleep four to five times (newborns spend about 50% of their sleep in REM, above the age of 5 this goes down to 20-25% then down again to 18% or less in old age -stages 3 & 4 can completely disappear in old age too). During REM sleep the person is completely paralysed, save for the heart, diaphragm, eye muscles & smooth muscles (e.g. muscles of the intestines & blood vessels).The brain is largely independent of its sensory & motor channels at this point, however discharging neurons that originate in the brain stem extend into the areas controlling eye movement and motor activites. This means that although the body is paralysed, the brain is registering activity from the areas of the brain associated with walking around and seeing the world, despite the fact it’s doing neither.
Thus Ends The Science
Well, for the most part.
So here ends Part 1, I hope you found it interesting! In the upcoming parts I’ll be discussing the difference between NREM & REM dreams/thoughts & some of the philosophical problems of gathering evidence for dreams. Hope you enjoyed this post and will stick around for more!
Feel free to leave questions & comments, I’ll answer them as best I can.
“All matter is merely energy condensed to a slow vibration, that we are all one consciousness experiencing itself subjectively, there is no such thing as death, life is only a dream, and we are the imagination of ourselves. Here’s Tom with the weather”
For many, myself included, consciousness is an odd thing. Some of this, I think, depends on your outlook on life. If you had a similar outlook on the world as say, Francis Crick (who discovered the structure of DNA and went on to put forward a theory of how consciousness occurs in his book ‘The Astonishing Hypothesis’) or Pat Churchland (who dismissively called David Chalmers’ famous distinction the ‘Hornswoggle Problem’), the chances of you perceiving qualia to be deeply problematic for science is unlikely. If one’s approach to consciousness were similar to David Chalmers (who unintentionally started a philosophical sensation by talking of the ‘hard problem’ of the mind) or Stephen LaBerge (who proved lucid dreaming occurs in REM sleep), it is probable that you will be sympathetic to the view that neural correlates in the brain may not provide all the answers to our questions about subjective experience.
In this brief paper, I want to discuss the view called Panpsychism, which sees consciousness as a fundamental feature of our universe, much like spacetime or mass. It has had its fair share of proponents throughout history, including such renowned thinkers as Spinoza and Liebniz, and still has its advocates today. What I find interesting about this view, and why I wish to discuss it, is because it at first seems so radically preposterous and anti-scientific, but it turns out to neither clash with any scientific data, and in some cases actually fits surprisingly well with it.
Our current knowledge of the brain reveals just how fascinating and complex it is, while also showing how much we still have to learn. We know that an average adult brain has about 100,000,000,000 (one hundred billion) neurons, with an average of 1,000 neurons connected to 10,000 others. The different ways they can be connected are staggering. The formula for the number of possible ways a neuron can be connected to others is 2(n*(m-1)/2), meaning that while there are only 2 possible ways 2 neurons can be connected, 6 neurons can be connected in 32,768 different possible ways! The different possible brain states an average brain can have, then, is an incredibly high number; so high that it exceeds the number of known particles in the entire known universe (Levitin 2006, p. 88). Yet, we do not even know how neurons code information; we know little about how it is achieved in the axon and even less about how decoding is done in the dendrites. So perhaps the conscious mind may remain elusive to scientific grasp, a view taken by, among others, Thomas Nagel (Read 2008, pp. 52-53).
Pat Churchland warns, and rightly I think, that it is foolish to try to judge how hard a problem is; one can never really know. In an interview with Susan Blackmore she points out:
“The problem of how proteins fold was thought to be an easy problem; whereas the problem of how information is copied from parent to offspring was thought to be really, really hard. Well, it turns out that the copying problem was basically solved between 1953 and 1960, but we still don’t know how proteins fold”
(Blackmore 2005, pp. 51-52)
The more interesting, misdiagnosed problem is that of the perihelion of Mercury. What appeared to be a relatively minor issue that seemed like we would just stumble across an explanation sooner or later actually became evidence that Newtonian physics was gravely mistaken; in other words, what seemed like a confusing but ultimately explicable problem given modern understanding actually required a fundamental revolution of thought.
Why is this relevant? The answer is that such misdiagnosis of problems within the scientific community raises the question of whether or not we will need to undergo another fundamental shift. Panpsychism is an argument for just such a fundamental shift.
Scientists take some things in our universe as just being fundamental, things like spacetime, mass, energy and the laws which govern these things. We have various particles, which in turn are comprised of yet smaller particles which form to make the elements; the chemical building blocks of the universe. Is consciousness just such a fundamental feature?
If we are to take this suggestion seriously, we must be clear why we might need to posit such a fundamental feature. Putting it in a similar way to how David Chalmers originally put it in 1994, the ‘easy problems’ that we have are those related to behaviour. Why does certain signals in certain neurons correspond with such and such behaviour? It might take some time, but we are at least aware of how we might go about solving these problems. The ‘hard problem’, and the reason we may need to posit consciousness as a fundamental phenomena, is why there is consciousness at all. Why is there this subjective experience we all undeniably have?
A common way of drawing this point out is by way of an example. The philosophical zombie is something identical to you or me in appearance and behaviour, different in only one important respect; there is no conscious experience involved. As Chalmers puts it, ‘you couldn’t tell the difference from the outside, but there would be nobody home inside‘ [author’s emphasis] (Blackmore 2005, p. 45). Now, such an example is not without its detractors and there are many scientists and philosophers who think such a thought experiment is flawed; Christof Koch, Susan Greenfield, Daniel Dennett, Pat & Paul Churchland, to name but a few. I do not have the space here to discuss the various objections levelled at the zombie thought experiment, I merely bring it up to serve as a tool to try and illuminate what we are specifying by ‘consciousness’.
Now that we have hopefully grasped what it is we want to explain, the big question is whether we can explain it without resorting to positing another fundamental part of the universe.
Firstly, it should be noted that panpsychism is not necessarily committed to the view that everything is in some respects conscious. Much like there are large areas of space which have no mass, we could suggest there were large areas of the universe where no consciousness existed. It might be fundamental, but it might also be very rare. This immediately avoids the objection sometimes levelled at panpsychism phrased along the lines of ‘To claim that this thermometer is in some respects conscious is just absurd!’.
We might put forward a view like the following. Consciousness is a fundamental and irreducible phenomenon in the universe, but it only occurs in some areas of the universe and under very specific conditions. Let us say the biological brain is just such a place where consciousness occurs (we need not specify what part of the brain, or which process, can generate/produce/instantiate/accumulate enough consciousness to form a mind -if there can be wholly separate minds, as Leibniz argued). This means we are admitting that consciousness is not unique to humans, which I find a perfectly acceptable consequence. Indeed, I find it objectionable to grant humans special status with regards to consciousness. This leads us to the first sort of argument that can be offered for the panpsychist view.
Assuming the theory of evolution to be correct, it becomes difficult to pinpoint the point in time where animals leaped from unconscious animals to conscious ones. Nowhere in the evolutionary time-line suggests itself for a point where consciousness just suddenly appeared. We know we have consciousness, but did our evolutionary ancestors? At what point did they become conscious as opposed to merely chimp-like automatons? This gives panpsychism a strong argument in its favour; we can’t find a point because there is no point where it suddenly appeared. In the lowliest forms of life there were very primitive forms of consciousness, and it becomes more and more complicated the higher up the evolutionary scale we go. Dolphins have greater consciousness than, say a grasshopper, but lesser consciousness relative to man.
A further argument in a similar vein is that evolution cannot develop entirely novel properties. That is, something fundamentally different from the available material cannot suddenly spring up out of nowhere. To put this in a rather extreme way so as to illustrate the point, a species of frog cannot just evolve the ability to turn into a ghostly aether-like substance and float through walls. Consciousness, it is asserted, is just such a novel property. This argument is slightly more difficult to evaluate as seemingly bizarre properties have evolved over millions of years; compare the archaeopteryx (the earliest known bird, which has more in common with lizards than it does modern birds) with a magpie, or sparrow. The panpsychist can point out that we can explain the development of feathers and wings by examining the different combinations of DNA; a certain combination of adenosine, cytosine, guanine and thymidine (the four letters, A, C, G and T which make up the ‘alphabet’ of DNA) produces such and such a bird like creature. We cannot make the same argument for consciousness, it is argued.
So we have seen that we can argue coherently that consciousness is a fundamental phenomenon of the universe. That it is rare and occurs only in certain situations, although which specific situations we cannot say, but can claim that one of them is in the brains of most animals at certain stages (humans brains, for example aren’t conscious during the times they are unconscious! -unless we are conscious at all times but do not remember certain periods of time). We have also seen that evolutionary factors give us at least one good reason to give the view some careful consideration.
There are two other issues related to panpsychism that I wish to look at. Firstly, whether or not it is a major issue that we currently cannot detect consciousness (other than knowing we ourselves have it and assume other humans and animals do too). Possibly. A good theory should be falsifiable; being able to fully account for consciousness without resorting to positing it as a fundamental phenomenon would be one way of going about it (taking Occham’s razor as one of our guiding principles). Recognising that consciousness is still very much as elusive as the Higgs boson is not a major barrier to accepting the theory. The fact we cannot prove the existence of time without being circular or trivial does not stop anyone from accepting it as (obviously) true, so too could we posit consciousness without worrying about proving, or finding (if this is even possible), conscious phenomena itself.
The other issue is to explain why groups of people do not, or cannot, share information via their consciousness. That is, why can’t two people standing close enough together share thoughts simply by pools of their consciousness crossing over? Here we may need to be extremely speculative merely to see if we can begin to form a coherent theory (this can hardly be considered a philosophical first!). Perhaps certain areas of the brain are able to affect consciousness (though obviously we are as yet in the dark about which areas pending further advances in neuroscience), in a similar way to how gravity can bend spacetime. Given that the processes are so small (dendrites, axons and neurons aren’t very big!), perhaps they are not powerful enough to affect consciousness more than a few millimetres (perhaps much less) away; similarly, weak gravitational fields have a negligible effect on spacetime. This would explain why we cannot share conscious thoughts. It would also go some way to explaining how consciousness arises in people at all; consciousness is manipulated/bent/imprinted in some way by the information being processed in the brain (perhaps coincidentally or luckily), and greater quantities are manipulated in more complicated brains (e.g. human). Hypothetically then, if we were able to create some sort of consciousness vacuum (where everything in the environment is the same except that there is no conscious phenomena), then we could place an ordinary human being in it and observe no difference in their behaviour. The only difference would be that we would have a living example of a philosophical zombie as mentioned earlier.
So to bring this brief discussion to a close, it must be admitted that much of this is highly speculative and much of the later discussion is simply how I think panpsychism might work if it were true of the world. As I mentioned at the start, I think acceptance of this theory may depend on one’s outlook rather than whether a solid argument can be put forward in its favour. Much in the same way that Lewisian modal realism may never be accepted no matter how many good arguments are put forward for it by genuine modal realists; it is just too bizarre for many to accept. I myself think that considerations of evolution as discussed earlier on actually make a good case for a view like that of panpsychism, and would relish at such a seemingly spiritual view of consciousness turning out to be correct. I do, however, remain sceptical of the position, even more so of the chances that the view will gain any significant ground in modern thought outside of fringe circles.
From a biological perspective, the human brain is not unique, it’s simply the most complex. ‘Not even the most experienced electron-microscopist could distinguish between tiny sections of brain tissue taken from humans, other primates, rodents or birds, except by context. The basic biochemistry and physiology of neuronal function has mainly been derived from work with…rats and mice…while the physiology of axonal transmission is based on…studies…with giant axons derived from the squid’ (Rose 2005, p. 142)
Blackmore, S. (2005) Conversations On Consciousness. Oxford University Press
Levitin, D. (2006) This Is Your Brain On Music. Atlantic Books
Read, R. (2008) The `Hard’ Problem of Consciousness Is Continually Reproduced and Made Harder by All Attempts to Solve It , Theory, Culture & Society, Issue 25, pp. 51-87
Rose, S. (2005) The 21st Century Brain. Vintage Books