Whilst philosophers have pontificated on the mind for millennia, it is only relatively recently that scientists (from a wide range of disciplines but broadly known as 'neuroscientists') have begun to take serious strides in elucidating some of the mysteries of the mind. Great developments in mapping brain interconnectivity and the molecular machinery of the synapse have enormously improved our understanding of how the brain works, but there are still large questions that remain unanswered. What is the origin of consciousness? Do humans have free will? How do we formulate memories? What is a thought? To some extent these questions are philosophical in nature, but technological advances have allowed neuroscientists to take many philosophical questions into the realm of empirical scientific method.
This blog is an attempt to demystify a topic that might seem beyond many lay readers. Throughout my future posts, I hope to be able to convey some of the more important messages to emerge from neuroscience in recent times. I will often pay homage to some great early discoveries and talk to you about some of the people that are giving their lives to understanding what it means to be human. Neuroscience is a field as rich in diversity as the brain itself and it is my hope that this blog will be of use to lay readers and neuroscientists alike as I try to relay some of the most exciting discoveries of neuroscience in an easily digestible manner.
Ermerson Pugh once said "If the human brain were so simple that we could understand it, we would be so simple that we couldn't". Well, perhaps he's right, but let's have a bloody good go!
Ermerson Pugh once said "If the human brain were so simple that we could understand it, we would be so simple that we couldn't". Well, perhaps he's right, but let's have a bloody good go!
Hey Paul,
ReplyDeleteGreat blog!
I know very little about the philosophy of mind, but am interested in the ways in which neuroscience can help answer philosophical questions. Could you maybe give a specific example of a result that has made progress on the question of the origin of consciousness? Also, are there specific philosophical questions about the mind that neuroscience has solved outright?
Thanks in advance for any help.
Best,
Sam
I was careful to phrase that in such a way as to convey that neuroscientists were taking these things into the realm of neuroscience but weren't necessarily getting there!
ReplyDeleteThere is a great deal of work on human consciousness (eg. http://www.ncbi.nlm.nih.gov/pubmed/20881487) and a lot of it is paving the way to understanding the neural correlates of perception with some astounding results. However, I would always argue that there is a fundamental problem inherent in the study of consciousness that arises from the fact that we can only assess someone's consciousness by what they report. We can never jump into someone's mind and actually feel they are experiencing what it means to be conscious. This is a philosophical barrier and I will happily concede that it does not help the progress of science by cowering behind it, but it is an important thing to 'keep in mind', as it were.
On the topic of free will, arguments have been made for the absence and for the presence of free will, but neuroscience has paved the way to at least understanding the brain areas involved in the decision-making process. The supplementary motor areas are heavily implicated as well as the parietal cortex and there seems to be neural activity some time before the conscious experience of volition (http://www.cell.com/neuron/retrieve/pii/S0896627311000766).
I don't believe that these topics will ever become purely scientific questions, but neuroscience continues to inform philosophers on what sort of questions they should be asking.
I hope that's helped Sam. If not, I'm always happy to discuss this topic further, particularly with a philosopher.
If you don't have institutional access to those pages I can send you the pdfs.
Regards,
Paul
Hey,
ReplyDeleteThanks for the response. I'll look at those articles when I get a chance (though I've glanced through).
"However, I would always argue that there is a fundamental problem inherent in the study of consciousness that arises from the fact that we can only assess someone's consciousness by what they report."
That's very interesting. I'm probably being dense, but wouldn't this kind of bar on investigation simply be a bar on investigation of consciousness full stop? Do you mean that any investigation of consciousness would have to proceed by surveying people, as opposed to studying the brain directly? (I assume not, because the first article you cited looked at the latter kind of evidence).
"On the topic of free will, arguments have been made for the absence and for the presence of free will, but neuroscience has paved the way to at least understanding the brain areas involved in the decision-making process."
I certainly don't disagree that such work has been done, as you say. But I'm finding it a little difficult to see how this kind relates to the question of free will.
I suppose if we assume that we have free will, and we want to know more about what happens in the brain when we exercise it, then this kind of work seems to help to answer that (assuming that exercises of free will are correlated with `conscious experience of volition'!). But, if we're wondering whether we have free will in the first place, I start to lose grip on how these studies will help to answer that.
Thanks again for all the help.
Best,
Sam
Hey again,
ReplyDeleteSo, I think I might understand you a bit better now. On the point about consciousness, was the thought this:
Suppose we want to study the neural correlates of being in pain. Then, in order to know that we are studying such correlates, we need to know whether the subject is in pain. But that means we have to ask them whether they are in pain, because their pain is in some way only accessible to them (being a conscious experience).
But then I don't see why that's a problem (scientific or philosophical). I mean, I suppose they could lie about whether they are in pain. But presumably there are ways to minimise this risk.
Best,
Sam
I don't see how you don't see that as a problem. Someone can easily be reporting something that isn't happening. Just like someone could be saying they are not aware of something when they are. Also, how do we know what constitutes a loss of consciousness? Take the vegetative state for example. We have absolutely no way of telling how conscious these people are of anything that is going on around them, regardless of whether the traces in the brain match people who are waking conscious. You might argue that the person could wake up and tell us he was conscious at the time. But how does he know? He is now experiencing a memory of conscious experience, which is totally different to being conscious of it in the first place.
ReplyDeleteI hope my friend Patrick is reading this. We have this argument so much, which is why I conceded that the work is not futile just because of this limitation. However, in my honest opinion, I don't think we will ever be able to unequivocally state what consciousness is in neurological terms for this reason.
I think the question is relatively simple in the case of free will. People cannot defy their brain, and if you look at it like that, then you could argue that there is no free will. However, people ARE their brains (largely), and so the fact that their brain's determine their decisions does not absolve them of their responsibility. Of course we are a product of our environment and genetic makeup, but that does not mean we don't make choices. That's what the brain is. When you look at it from this angle it is sort of moot point in my opinion. But I can't seem to work out if that is radical or philosophically flawed. It's just what I think.
In summary, no, I don't think neuroscience will ever truly drive at either of these problems, but don't tell my research pals I said that!
Hey,
ReplyDeleteAs I said, it's possible that people will report being in pain, say, when they aren't. But I take it that this is always a risk in research of this kind. We shouldn't confuse a healthy scepticism with out and out scepticism.
I agree that the vegetative state cases are more difficult. For the same reasons as above, though, I don't think it is very helpful to doubt (in general) whether the persons memories are accurate (and presumably we know quite a bit about the accuracy of memories which we could use in these cases). But suppose they don't wake up. Then I take it that the proper method is to develop a theory of consciousness based on waking subjects, and apply that to those in a vegetative state, no?
Best,
Sam
OK, fair point about the pain. Someone is unlikely to report it if it isn't there.
ReplyDeleteBut I think you're wrong about the vegetative state. How can someone know whether they were conscious of something at particular time? How can you disassociate the memory trace from the actual experience? Imagine, in the future, we are able to implant memories (which I believe that we will definitely be able to do), would that person feel like they were conscious of the event they are remembering at the time? I would think so. So do you see how I think that the memory and the conscious experience are different.
If they don't wake up, I feel like you would just be speculating, albeit with some basis, as to what they were experiencing, and I don't see neuroscience getting round that as brains are individual. I may be wrong though!
What a mental workout. Not as 'fit' as I used to be
ReplyDelete"Imagine, in the future, we are able to implant memories (which I believe that we will definitely be able to do), would that person feel like they were conscious of the event they are remembering at the time? I would think so. So do you see how I think that the memory and the conscious experience are different."
ReplyDeleteI agree completely. In this case we certainly shouldn't trust this person's memories. And in general I agree that a memory of X is not the same as X. But that is true for any value of X.
Suppose we have a person wake up from a vegetative state, and we know that they haven't had their memories replaced, and that before they went under they were generally reliable truth-tellers. Further we can assume that the vegetative state would not have affected this attribute. Then suppose they tell us that when they were under they imagined fighting with a bear. I see no reason to doubt in this case that they really did imagine such a thing.
If we replace `imagined fighting a bear' with `were conscious of a pain in their big toe', I don't see that anything important changes.
I mean, I take it that people who are conscious whilst under anaesthetic are a case in point. Do we have good reason to doubt these people in general?
"What a mental workout. Not as 'fit' as I used to be"
:-D
It's fun, thanks!
But when they talk about fighting the bear, they are telling us about a memory they are experiencing at that time and not a conscious experience and the distinction, I believe, is important.
ReplyDeleteHey,
ReplyDeleteOk, maybe I'm starting to see your point now!
Just to be clear, though, what do we say about a person who goes under anaesthetic and reports being conscious of the pain of her operation?
She is presumably reporting a memory of having a conscious experience of the pain. Why shouldn't we believe her that the memory is veridical?
Thanks again for all the help.
Best,
Sam
It's not about truth. Her memory may well be there. It is the distinction between the memory of an event and the actual subjective experience of that event in real time. The memory could come after having no conscious experience of the event at all, but she would still report being conscious of it. Do you see?
ReplyDeleteI see that the memory could come after having no conscious experience of the event. But I don't see why we should think that the memory isn't, as she reports, of a conscious experience.
ReplyDeleteIs the thought something like this: if someone reports a conscious experience in real time, then it is only marginally likely that this will be wrong. If, on the other hand, someone is recounting a conscious experience from memory, then there is much more chance that they will get it wrong?
The thought generalises: if someone reports an event in real time, then it is not very likely they will get it wrong (again assuming favorable conditions). But if they report an event from memory, then there is more chance they will get it wrong.
I of course agree with this. Memories are presumably less reliable than real time testimony. But it seems to me an unreasonable step from that premise to the conclusion that memories shouldn't be trusted.
My memory of the curry I had earlier is a very good indicator that I did in fact have a curry earlier. Similarly, my memory of being conscious when eating my curry is a very good indicator that I was conscious when I ate my curry.
Am I missing something?