Consciousness on-off switch discovered deep in brain
newscientist.com
newscientist.com
But Crick's notion sounds a lot like what Dennett derisively calls the "Cartesian Theater", the tendency to imagine consciousness as little room where a tiny homunculus watches the screens where all sensory data is displayed: http://en.wikipedia.org/wiki/Cartesian_theater
In Dennett's view, consciousness is basically a distributed system. There is no single place where consciousness "really happens". That a single electrode can disrupt consciousness doesn't suggest otherwise. If a backhoe hitting a cable junction triggered an AWS failure, we wouldn't say that the cable junction is where AWS "really happens".
If we take a signal like a certain sound that evokes an experience, or we can even ask the person to do some conscious processing based on the sound, the sound could be a question like "what is the color of the sky?". We can follow the signal: We can see first some mechanical preprocessing steps in the ear, then some neural preprocessing steps, and the signal is branched out, lots of different brain areas are probably activated and then again some fine movement post processing steps are done so that the person finally answers "blue".
I think it would be premature say that all the trivial very low level preprocessing steps in the ear are just as a relevant part of the conscious experience of hearing the question, as the understanding of the question.
Say, in a stretched analogy, if someone would like to understand how the computer can calculate some ray tracing or use some compression algorithms, it would not be that important to just understand how on die caches or PCI express lanes work. The important bit is to understand how instructions cause the ALU:s to wrangle the bits in registers, that's the core of the magic, most of the other stuff is relatively trivial pre- and postprocessing.
So in this sense I think the question is well posed.
There's also practical implications. Think if we could have reliable anesthesia (or the hypnosis part of it, you might still need pain killers and muscle relaxants). We might have very few side effects. We would not have to give big doses just to be safe. This could mean much faster recovery after anesthesia. Also costs of anesthesia would drop immensely if it could be even better controlled than it is now. It costs a lot to stay in a hospital. Also if you're unconscious, you have to be taken care of, again tying people...
As long as we're on the topic of targeting the claustrum specifically with pharmaceutical agents, I'll point out that the claustrum has a particularly high density of kappa opioid receptors, which are the target of salvinorin A, the active constituent of the psychotropic plant Salvia divinorum [1]. Of course we have no evidence the plant's effects are specifically related to its action in the claustrum.
[1] Smythies, J., Edelstein, L., & Ramachandran, V. (2012). Hypotheses relating to the function of the claustrum. Frontiers in Integrative Neuroscience, 6. doi:10.3389/fnint.2012.00053
What if instead of a cable junction for AWS, it was more like a clock in a CPU? Then it is part of what "really happens," but only a part.
Well, the cable junction is also part of what really happens.
So the example is not that different.
Not quite as much. If the cable junction fails, someone downstream of that junction won't have access to the calculations, but someone upstream of it still will. Whereas, if the clock in a CPU fails, there's no calculations happening anywhere.
If the claustrum is a junction connecting myriad systems, enabling coordinated forms of mental life, possibly consciousness, then in a sense, it could really be a key to consciousness.
Calling this critical juncture key to consciousness is not saying the claustrum is a theater where a homunculus watches everything come together, or that consciousness happens in the claustrum.
Consciousness is a state of the brain where disparate systems interact, and the claustrum may be key to explaining that coordination in consciousness.
Borrowing the car analogy in the article, the ignition system isn't where a car "runs". Nonetheless, the ignition is key to explaining how everything that comes together to put the car in a running state. I think people are misreading what the investigator meant when he suggests the claustrum might be key to explaining the conscious state.
Am I wrong here? Somebody quote me the passage I'm missing where the investigators say the claustrum is where consciousness happens, rather than just saying that the claustrum may be key to understanding how consciousness happens.
As a classically trained scientist, I fail to see how this can be newsworthy given how big of revelation this would be to broader scientific discovery and how statistically invalid this claim is at this point.
However, as legend would have it, psychologist B.F. Skinner was famous for performing his experiments on a single cat/dog. When prodded by other psychologists on how he could claim his results were valid since he only tested it on one subject, he would say "Well, bring me your cat"
I guess my main quip is how matter-of-fact this article expresses the finding!
Then again, I may just be arguing over semantics and not taking the gist of the finding. I appreciate your simple note to remind me of the fact that the finding is the cool thing, not the words used when being reported!
I'm only looking this field from far, as public interest does, but I kind of remember reading brain can actually reorganize so that impaired zone's functionality are transferred to other ones, to compensate.
If I'm not mistaken here, doesn't this make using a single subject even more of a problem in neuroscience than in other science experiments ?
Not that I am arguing against other minds, mind you. It's rather that a starting point of classical science doesn't really get one anywhere in regards to consciousness. We are always performing an induction from the one we have privileged access to for any claim about others
Obviously these are Matrix-type thoughts. I am just trying to explain brudgers point.
Rather it is about consciousness in the philosophical sense, that starts with the question of whether or not anything outside of your own consciousness even exists, and if we posit the existence of a real world, whether or not other seemingly thinking, self-aware, conscious entities exists that are able to experience consciousness.
Since we don't know what gives rise to this form of consciousness, it is not evident whether or not there will ever be any evidence to determine whether they are conscious or not in that sense.
"Consciousness in the philosophical sense", to the extent that it's a meaningful thing to talk about, is part of reality.
Stronger statement: "consciousness in the philosophical sense" is either part of reality, or a meaningless construct invented by philosophers to justify metaphysical speculations, thus obtaining job security by having a permanent claim that some phenomenon actually exists that can never be reduced to science.
'It's only appearances' skepticism always includes "to me". It only works by induction on the skeptic's solipsism. The difficulty of your position is compounded by HN's interface - even the claim "it appears to me that you are made of meat" is implausible.
Leaving aside the difficulties in unpacking the idea of scientific introspection under the classical rubric of experiment as observation, once one decomposes consciousness to where a scientific level can be extracted, there's a corpse on the table not a patient. The whole gist of consciousness is that it's unified and once we admit a distinct 'scientific level' we ought to own up to what we have done and say "by consciousness I don't mean what is ordinarily meant, but instead I mean exactly 'x,y,z' and therefore my claims are not about consciousness in general but about this special definition."
And there's nothing wrong with that, and it might be useful.
A better question would be "how can you try to understand consciousness without instrospection?" Studying consciousness merely by performing brain scans and electroencephalograms, without asking the subject what she's experiencing, would surely provide a poor and incomplete perspective.
Once we start talking about consciousness we're outside the realm of Newton's billiards balls and calculus. We're into psychology and navigating a linguistic sea full of terminology that owes more to Chaucer than Roger Bacon. A call for a larger sample size isn't going to give us a mathematical demonstration of any property of consciousness - it's just going to give us a claim on a larger confidence interval. It's going to make us feel better about our beliefs not show why they are correct.
I guess my point is that psychology is disjoint from 'classical science's simply because we cannot abstract its subject matter out of ordinary language and into mathematics. That doesn't mean we can't investigate it, just that we need to recognize the limitations imposed by the tools at our disposal. In programming terms, it's a ball of mud. Standardizing test conditions for investigating consciousness probably requires assumptions about states of consciousness upfront, e.g. sleeping, drowsy, awake, alert, and distracted. It probably relies on our nonscientific intuitions as well - trees and earthworms are right out and we're a long way from having the tools to investigate what it is like to be a bat in a scientific manner that feels continuous with the scientific method as applied in a field such as chemistry.
The subject's state could be compared to somebody in certain phases of sleep or in a coma. Not the same as those, but quite close. A quote in the article describes her as being 'still awake', but I wonder what that means.
It's not like the subject became a zombie. According to the very brief description, she just became completely unresponsive, didn't do anything, and had no memory of what had happened.
she gradually spoke more quietly or moved less and less until she drifted into unconsciousness.
That part of the process sounds very similar to someone undergoing anesthesia, or simply falling asleep. Though there are obvious differences.
So maybe that's what it feels like? Some people remember the feeling of going under, but maybe not the last few seconds of it.
I suppose both physical and neurological observable processes that as we know define 'sleep' and 'awake': her eyes were open but with a blank stare and so on, and since they said she did not exhibit neural signs of epilepsy, she was wired to an EEG, so brain patterns would possibly not be matching any phase of sleep but wakefulness.
That's all that could be inferred from the article, which is honestly quite thin and sensationalist.
In contrast, patients in a persistent vegetative state are awake, but not aware. It sounds like the researchers may have replicated this state of consciousness, which would imply that the claustrum is important in awareness, but perhaps not as critical in wakefulness, at least in this particular subject (keeping in mind that her brain is already abnormal in some sense due to epilepsy and neurosurgery that excised the left side of her hippocampus).
This paper has a nice review of the topic: http://www.coma.ulg.ac.be/papers/vs/2005_VS_TICS.pdf
"Koubeissi thinks that the results do indeed suggest that the claustrum plays a vital role in triggering conscious experience. "I would liken it to a car," he says. "A car on the road has many parts that facilitate its movement – the gas, the transmission, the engine – but there's only one spot where you turn the key and it all switches on and works together. So while consciousness is a complicated process created via many structures and networks – we may have found the key."
Thank you
I actually didn't focus much on the end of this excerpt. And I should have added the following in my original comment - I actually honed in on this part:
"but there's only one spot where you turn the key and it all switches on and works together"
Immediately after I read this, I actually imagined the key turning off, and the car shutting down. This is precisely what the author/surgeon stated happened during the surgery.
Also, I was too going to point out that 'clé' comes from French too. Maybe an etymology dictionary says it comes from Old English, but English is of course partially derived from Old French as well as Norse/Germanic languages [1].
Saying that I liked a metaphor because it contains Germanic words (like much of the English language) that occurred last is a nice theory. But what if I preferred softer sounding words for some other reason and had a bias against Germanic words - say because I studied French in school, lived in France or had grandparents that died horrifically during WWII.
I didn't downvote FYI.
But another theory as to why I liked it is because that passage instantly helped me to understand what the author believes the incredibly complex system the brain is like by using a simple rhetorical device called a metaphor.
On the important subject of whether or not consciousness is actually switched on and off in the claustrum, as a non-neuro-professional I have to grant his metaphor some credence and resolve to investigate further.
[1] http://en.wikipedia.org/wiki/Old_English#Influence_of_other_...
Is it terrible or just imperfect?
I've come to the conclusion, that science will never be able to even define consciousness, let alone explain it.
Pretty much. Consciousness is one level above science in a way, so every attempt to only use science to explain consciousness will fail. Consciousness is a metaphysical concept, "meta" = an abstraction layer above.
The first thing should be to define consciousness IMO.
> trying to create machines that display consciousness
In other words, trying to create machines that behave like humans? I don't know what "displaying consciousness" means.
It appears that mice have a claustrum, and I would be very interested to see the effect of manipulating that area on their behaviour. If it has little effect, one might conclude that mice don't experience consciousness the way we do, for example, or the reverse.
Edit: here is an open access version of Crick & Koch's paper on the claustrum:
Also, as the article points out, reversing the process could potentially be useful in awakening coma patients.
Of course all that's very speculative, and more research is called for, but that's how science is done.
I think the real problem is that people don't really want consciousness defined. They want to keep it as this magical, special thing.
I disagree, what makes you think so? Hard problem of consciousness is the real problem. Consciousness isn't a physical thing, that's why physics can't define it.
Says who? It is most certainly caused by physical neurons which are built by particles following the laws of physics. In principle it is both understandable and explainable in terms of physics, though likely any explanation will follow some other nomenclature (e.g. we don't describe weather in terms of motions of quarks)
The reason physics can't define consciousness isn't that consciousness isn't physical. Consciousness is just part of the world our current physics, and really our current philosophies, haven't developed satisfactory means to address.
Many physical phenomena, now explained by physics, were once unexplained by previous iterations of physics. Previous physics were just incomplete, until people came along with new ideas to expand what phenomena physics could explain. Doesn't mean those phenomena weren't physical things before physics evolved ways to understand them.
If they indeed found an on/off switch, it'd be interesting to attempt to "kickstart" some coma victims. If it works, it'd be a major breakthrough.
So, it may be a while before you see that follow-up study.
On a side note, the combination of antibiotics with fast recovery of injured soldiers has been very beneficial to neurology, as it meant that neurologists saw more living patients with horrific brain injuries.
It is unlikely that anybody would find this in patients with traumatic injuries, though. A projectile damaging this area deep in the brain likely would take out lots of other areas, too, and would be lethal, even if one gets the patient in a hospital within minutes.
But they seriously need to test that on someone with an intact hippocampus.
Additionally, consciousness gets commonly defined in philosophy of mind as the "likeness" of sensation and perception (i.e. its "like" something to smell roses and its "like" something to hear Mozart). So, this study cuts at the root of consciousness.
Also, the article keeps saying the claustrum, but don't we have one in each hemisphere? Which one did the scientists stimulate, and what would happen if you stimulated the other one?
As a software analogy, think about a very large and complex, undocumented code-base in a bizarre language you've never come across. Your only experimental tool is to pick a line of code, delete/modify it, and then see what happens. As you learn more, you can do refine your experiments but basically, you're still just 'poking it with a stick'.
We call that a "debugger" around here. You are expected to know the jargon before applying for patents.
But obviously it's a lot more than that, and so is electric brain stimulation.
What is/are the appropriate scales to study brain function at? Quarks? Molecules? Brain regions? Which ones? All the above? None? We need to know the answer in advance before pronouncing a method "crude", or conversely, "too precise", by some criteria.
We don't know the answer to the scale question but poking "areas" to build up a fuzzy picture of regional function at first approximation is getting us there.
Would the knowledge gained from knock-out/stimulation experiments be more fine-grained if the investigators already had a fine-grained understanding of what they were studying and thus, the cleanest way to study it? Yes.
But breakthroughs are not made where investigators know what they're doing. Breakthroughs are made where nobody knows what they're doing--often crudely, frequently accidentally. The history of scientific advance is messy. Significance of results doesn't map neatly to sophistication of methods/tools.
I wholly agree that neuroscience has a long way to go. But to me that doesn't diminish the achievements of neuroscientists pushing us there, using whatever ethical opportunities available to them.
http://en.wikipedia.org/wiki/Claustrum
I find this more interesting than 'rebar through the eye' style stuff like the Phantoms in the Brain book by this guy: http://en.wikipedia.org/wiki/Vilayanur_S._Ramachandran
It's more interesting since they mention consciousness, though I don't know what they're really talking about.
I think stuff like 'rebar through the eye' has revealed interesting 'machine learning'-type defects, like funny ways your vision can be messed up and see at a very low fps, unable to perceive most quick motion.
But machine learning is popular and stuff because it works, unlike strong AI and consciousness, which are pretty difficult to get any handle on.
Fundamental physics is done by smashing particles together and seeing what happens. We've gotten tremendously far with this approach. Do you have a better idea?
Not necessarily. In the 1950s and 1960s when we started exploring higher energy levels, we didn't really have a model or theory that predicted all the particles we ended up seeing. That came after.
Here is the episode if anyone is interested: http://www.radiolab.org/story/black-box/
This is how it sounds to me.
Right, counter-intuitively... As long as we'll be making up reasons based on that piece of data, how about this:
Global synchrony occurs when a brain is recovering from an unknown or detected bad state, and all major parts of the brain say "HLO" to each other to notify for their existence, proper operation and to establish connection. So it's not that it's bad to be synchronous, but the lack of information from critical parts of the brain causes it to repeatedly reboot in order to recover from a bad state forced by electric rods in the brain.
Hey, I'm a scientist!
Seriously though, why aren't we thinking about what the implications of our experimental data would be on a distributed computing system, which our brain is, instead of giving silly "it's like the key in a car" explanations, assigning causality randomly and without merit?
The stated "counter-intuitive"-ness is more likely an artifact of the translation of the result to layman's terms, where the traditional (since the industrial revolution) way of thinking about the brain and mind is that it is a machine, and the function of this machine is consciousness. I think several such artifacts often appear in these sorts of articles on neuroscience.
If you wish to actually understand and interpret the results for yourself, without the crude and inevitably inaccurate lens of the science writer, you have to read some of the books written by neuroscientists themselves. Rhythms of the Brain by Gyorgy Buzsaki is the best I've read so far.
And yet, nothing you said really rejects my made up explanation, even more, it supports it (the visual center stops sending information as it lacks input, and synchronization attempts begin).
http://www.newscientist.com/article/mg22329762.700-conscious...