How the Brain Does Consciousness: Biological Research Perspectives

[Piggy]

Piggy, please stop telling everyone who disagrees with you to leave the thread. It's kind of annoying.

It's not a matter of disagreeing, it's a matter of either discussing the topic in the OP or not. I'm not trying to tell any poster to leave, although there are topics I suggest belong in new threads.

I would rather that folks who post stay on topic, for the most part. Tangents are inevitable, and I'll get on them, too, but clearly this thread is intended to be a discussion of brain research into consciousness from a biological perspective.

Interpretations of the conclusions drawn from the research, and the validity of the set-up, that sort of thing surely fits within the OP, but in order to do that you have to be talking about some sort of research or other.

 

[Piggy]

Ok, back to the topic.

I wish I could recall the cite, don't know if I ran across this in one of the books or SD or where, but I recently read some studies into what the brain is doing during eye movements, and it turned out that the brain was continually imagining the patterns that would result from eye movements.

This has been interpreted as a prediction mechanism, a simple, low-cost way of identifying anything that needs attention. Where the imagined and perceived patterns differ, pay attention.

We're not, of course, aware of this type of imagining going on in the brain, which is interesting because we've always thought of imagination as a purely conscious endeavor -- one that we would always be aware of, even if we were letting our minds wander and not trying to direct our thoughts -- but it turns out that our brains imagine in ways that don't involve our conscious awareness at all.

And the attention is interesting, too.

In "Human", Gazzaniga mentions that voluntary and involuntary attention use overlapping but distinct real-estate in the brain. (If anyone wants the cite, I can look it up and check his endnotes.)

But with regard to imagination that we are conscious of, much of the same real estate is being used, the same areas engaged for imagining an experience as actually being in it.

Alan Leslie called it a decoupling mechanism, however the brain manages to distinguish. Obviously, in some people it doesn't work as it should -- for a variety of reasons, I'm sure -- and they have a hard time coping.

But anyway, it's cool to know that my brain is continually imagining things I have no idea of.

 

[Beelzebuddy]

It's not a matter of disagreeing, it's a matter of either discussing the topic in the OP or not. I'm not trying to tell any poster to leave, although there are topics I suggest belong in new threads.

Coulda fooled me, you've told everyone who's disagreed with you so far to gtfo. And yeah, "take your posting to another thread" is actually telling them to leave. They wouldn't have put it here if they didn't think it was relevant, and in most cases it has been. I've seen more open-minded fundamentalists.

 

[Third Eye Open]

Note that these researchers use a different definition of consciousness than what you are using:In fact it is the sort of consciousness that you said you didn't want to talk about:
Also the study is done on rats, for which it is an open question whether they have the "Sense of Individual Awareness" you are describing. Lastly it is done by scientists who are not so sure consciousness is a property of the brain...... even though you said you want to limit the discussion to the brain.

Doesn't seem relevant to the kind of consciousness you want to talk about either. No attempt is made to determine whether the same things occur during dreaming.

Yes, I would consider myself blind. But blindness in these people is sort of an illusion; as they can respond meaningfully to visual stimuli.

I agree that it is tremendously interesting, but I am not so sure it tells us a lot about the nature of consciousness yet. It seems to me more of a problem research into consciousness has yet to tackle.

I don't think it is off-topic. It is relevant to your claim that consciousness is a "resource hog" and that yet natural selection has favoured it. If it really requires so much resources, then there must have been times and places where it wasn't favoured and it would be likely that there is considerable variation in consciousness in humans.

Just bumping this cause I think it's funny.

 

[TmoonII]

Is illucid a word?

I don't mind critical thinkers who deny cellular memory plays a part in consciousness. That's fine.
http://www.hhmi.org/research/investigators/kandel.html
http://www.physorg.com/news157906808.html

 

[rocketdodger]

If you have a question about a particular study that's been cited, and the conclusions drawn from that study, then you're perfectly free to join in.

I question your conclusion that consciousness is some sort of "resource hog" and thus there must be some underlying reason why it was selected for in humans.

You don't seem to accept the much more likely scenario that consciousness is simply the same thing as all of the separate brain activity going on -- stuff that clearly has good reasons for being selected.

Note that at least two other participants in this thread seem to agree with me in this sense.

 

[Beelzebuddy]

Is illucid a word?

I don't mind critical thinkers who deny cellular memory plays a part in consciousness. That's fine.
http://www.hhmi.org/research/investigators/kandel.html
http://www.physorg.com/news157906808.html

Yeah, those links don't say what you seem to think they're saying. Kandel in particular would take grave offense at that; he's a molecular biologist so crusty he's used by other scientists as a guideline for "this is being too hardcore." He literally wrote the book on neurobiology. And he looks astonishingly like the Six Flags guy, though that's more from the bow tie than anything.

 

[TmoonII]

another knock out statement.

 

[Piggy]

You don't seem to accept the much more likely scenario that consciousness is simply the same thing as all of the separate brain activity going on -- stuff that clearly has good reasons for being selected.

The same thing as which separate brain activity?

Clearly, it's not the same thing as all separate brain activity, since we're not aware of everything our brains are doing.

ETA: It will certainly, in a sense, turn out to be "the same thing" as some brain activity.

 

[Piggy]

I've started reading Nicholas Shiff's article on recovery of consciousness after brain injury. Hoping there's interesting stuff there.

The challenge at hand is to assess the conscious states of patients "with very limited or even no overt signs of behavioral responsiveness... consistent with clinical diagnoses ranging from vegetative state (no sense of self or environmental awareness), minimally conscious state (at least some evidence of awareness), and up to but not including patients in a locked-in state (full consciousness with no motor control)".

Will drop relevant bits as I run across them.

 

[rocketdodger]

The same thing as which separate brain activity?

Clearly, it's not the same thing as all separate brain activity, since we're not aware of everything our brains are doing.

ETA: It will certainly, in a sense, turn out to be "the same thing" as some brain activity.

You don't seem to understand. Let me give you an example -- self awareness.

You have asked numerous times "what survival advantage does our conscious awareness of self give us?" I don't see why that is a hard question -- it is obvious why an entity with self awareness would have survival advantages over one that does not. And we have self awareness. End of story, right?

No. For some reason, you try to take it a step further, and suppose a difference between self awareness and the kind of self awareness we have, as if there *still* needs to be an explanation for why evolution led to it. But why? What is your reason? Where is the evidence that our self awareness is somehow different than ... self awareness?

What evidence do you have that our human conscious awareness of ourselves is anything above and beyond just plain old self awareness -- the kind a frog has? If you take a frog's self awareness, and start adding on the complexity of being a human -- a more detailed body map, memory, language, better sensory perception, etc -- who is to say that you won't just arrive at human self awareness?

So then the answer to "why did nature select for our conscious self awareness?" just becomes "in an entity as complex as a human, why would self awareness be better than no self awareness?" and the question to that is trivially simple -- there is no such thing as an entity as complex as a human that is not self aware. What on Earth would a non-self-aware human even be like?

 

[Piggy]

You're right, RD, I don't understand. I can't even recognize my own views in your description of them. I just have no response to that.

 

[Piggy]

Here's an interesting case from 2006, the first use of neuroimaging to obtain clear evidence of conscious awareness in a physically non-responsive patient using command following (Owen et al, Directing awareness in the vegetative state, Science).

Functional MRI images of the brain of a patient asked to imagine playing tennis and walking through her house showed activity in the same specific brain regions as control subjects asked to do the same.

What's weird about this case is that Owen & co demonstrated that the motor pathways were intact, but also had reason to believe that the patient could not have been "fully conscious".

If all that is accurate, we're talking about a conscious state in which one can follow commands, engage in imagination, but not initiate physical responses or conceive of any "goal directed intentional behaviors because of generalized cognitive impairment".

The problem is, when it gets that weird, how do you come to any conclusions about "what it's like" in such a state?

 

[Piggy]

Note that these researchers use a different definition of consciousness than what you are using:In fact it is the sort of consciousness that you said you didn't want to talk about:
Also the study is done on rats, for which it is an open question whether they have the "Sense of Individual Awareness" you are describing. Lastly it is done by scientists who are not so sure consciousness is a property of the brain...... even though you said you want to limit the discussion to the brain.

Doesn't seem relevant to the kind of consciousness you want to talk about either. No attempt is made to determine whether the same things occur during dreaming.

Yes, I would consider myself blind. But blindness in these people is sort of an illusion; as they can respond meaningfully to visual stimuli.

I agree that it is tremendously interesting, but I am not so sure it tells us a lot about the nature of consciousness yet. It seems to me more of a problem research into consciousness has yet to tackle.

I don't think it is off-topic. It is relevant to your claim that consciousness is a "resource hog" and that yet natural selection has favoured it. If it really requires so much resources, then there must have been times and places where it wasn't favoured and it would be likely that there is considerable variation in consciousness in humans.

Just bumping this....

Well, if someone thinks it's worth bumping for whatever reason....

The study encompassed people and rats:

Shulman and colleagues have proposed that it is needed to maintain a person in a state of consciousness. Heavily anesthetized people are known to show approximately 50 percent reductions in cerebral energy consumption. When the paws of lightly anesthetized rats with rather high baseline energy levels were stroked, fMRI signals were received in the sensory cortex and in many other areas of the brain. In heavily anesthetized rats the signal stopped at the sensory cortex. Both the total energy and the fMRI signals changed when the person or animal lost consciousness.

So apparent loss of consciousness in people and rats is associated with a change in fMRI signals and a reduction in total energy.

In the previously cited study on anesthesia, we see a re-establishment of active networks and a strengthening of connections when consciousness is regained, so that obviously requires resources to accomplish.

As for the definition of consciousness at the intro of the piece, let's look at that in context:

At its simplest, consciousness can be defined as the ability to respond meaningfully to external stimuli. Most studies of consciousness have used imaging technology to try to pinpoint areas of brain activity during tasks such as memorization or problem solving.

There are two problems with such an approach, said Robert G. Shulman....

So I wouldn't worry about that, since it's being argued against.

In any case, the stipulative definition here is intended to be broad enough to allow a lot of research in, and to prevent needless objections because, for example, dream studies are of "unconscious" people, or nothing matters unless self-consciousness is demonstrated.

I don't necessarily agree with Schulman's statement that "You can think of consciousness not as a property of the brain, but of the person", btw. But I still think the research is interesting.

As for the implant studies, no, they don't publish anything about dreaming, but that doesn't matter.

I don't guess I have anything to say about the possibility of certain people's blindness being an "illusion".

 

[sol invictus]

The problem is, when it gets that weird, how do you come to any conclusions about "what it's like" in such a state?

It's not that weird. It only seems weird to you because you believe that there really is some distinct thing called consciousness that either is present or isn't.

But in reality there probably is no such thing. There's just a bunch of brain processes, some of which a functioning normally in that patient and some of which aren't.

The moment you define consciousness in a strict way - "you're conscious of something if you can vocally report it", for example - all the "weirdness" goes away. Patients are either conscious or not. But if you just have a vague feeling about what it ought to be in your opinion, there's lots of room for "weirdness".

 

[Piggy]

It's not that weird. It only seems weird to you because you believe that there really is some distinct thing called consciousness that either is present or isn't.

But in reality there probably is no such thing. There's just a bunch of brain processes, some of which a functioning normally in that patient and some of which aren't.

The moment you define consciousness in a strict way - "you're conscious of something if you can vocally report it", for example - all the "weirdness" goes away. Patients are either conscious or not. But if you just have a vague feeling about what it ought to be in your opinion, there's lots of room for "weirdness".

Well, I can assure you that most of what you think I believe isn't actually something I believe.

But to the last point, no, "conscious or not" doesn't seem to be the way it works.

The question is, conscious of what? And the as-yet unanswerable question is, conscious in what way?

 

[Beelzebuddy]

Well, I can assure you that most of what you think I believe isn't actually something I believe.

Then correct him. Explain. Elucidate. Freakin' talk. Don't just dismiss everyone and go off on wild-ass tangents. This is a discussion forum, not a collection of soapboxes. If he's misunderstanding your position, learn him the hell why.

 

[TmoonII]

Piggy, can you post a link for the 2006 Owen et al research? thanks.

 

[Beelzebuddy]

Here you go. I dunno if you can access the full text, but the abstract pretty much says it all. They fMRI'd a patient thought to be vegetative and found brain activity more reminiscent of an aware and alert individual, i.e. "locked-in syndrome."

 

[Guybrush Threepwood]

Well, I can assure you that most of what you think I believe isn't actually something I believe.

You have probably hundreds of posts in this thread and the other recent consciousness thread and I still have no idea what you believe. I thought it was maybe that I'm just not capable of getting it.

Then correct him. Explain. Elucidate. Freakin' talk. Don't just dismiss everyone and go off on wild-ass tangents. This is a discussion forum, not a collection of soapboxes. If he's misunderstanding your position, learn him the hell why.

Then again, maybe it's not just me.
Can you explain what you actually believe about consciousness in a single post. That way the rest of us might be able to discuss it sensibly with you.