How the Brain Does Consciousness: Biological Research Perspectives

[sol invictus]

So what is Sofia doing?

Clearly it must be doing something, or evolution would not have bothered to select for it, and my body would not expend resources to maintain it.

You are assuming "Sofia" exists, a fact not in evidence.

But it's a hard thing to really comprehend, that even as I watch myself type this, I've already finished typing what I believe I am typing right now in the moment.

The implications of this bit of modern knowledge are profound indeed.

I don't think so.

To me, by far the most likely scenario is that "consciousness" is nothing more or less than a sequence of brain states that have evolved so that we can eat, sleep, reproduce, etc. If you want to call that sequence "Sofia" go ahead, but there is nothing mysterious about why it evolved, or why our bodies expend the energy necessary to sustain our active brains: it's obviously an advantage to have a functioning brain directing the body's actions. That's all.

 

[Piggy]

To me, by far the most likely scenario is that "consciousness" is nothing more or less than a sequence of brain states that have evolved so that we can eat, sleep, reproduce, etc. If you want to call that sequence "Sofia" go ahead, but there is nothing mysterious about why it evolved, or why our bodies expend the energy necessary to sustain our active brains: it's obviously an advantage to have a functioning brain directing the body's actions. That's all.

Well, yeah, it seems to me that this is pretty much in line with the current research.

The term "Sofia" is just a means of saving keystrokes. It is not intended to imply anything mystical at all.

 

[Piggy]

You are assuming "Sofia" exists, a fact not in evidence.

Well, unless you claim that you are not self-aware, then Sofia is indeed a fact in evidence.

In any case, current research into how the brain generates conscious experience does not doubt that human beings -- and probably other animals -- have a sense of felt individual awareness.

If you know of any brain research regarding consciousness which takes a different stance, feel free to post it.

 

[yy2bggggs]

You are assuming "Sofia" exists, a fact not in evidence.

I don't understand this objection.

 

[sol invictus]

Well, yeah, it seems to me that this is pretty much in line with the current research.

The term "Sofia" is just a means of saving keystrokes. It is not intended to imply anything mystical at all.

If all you mean by it is brain functioning, there's not a whole lot of mystery about why it evolved and why we expend the energy to maintain it.

I don't understand this objection.

Many people seem to believe that there is something more to consciousness than a sequence of physical brain states, for example that it's not something a computer could possess (sorry Piggy). I don't think there is any evidence - or even any argument - for such a belief.

 

[Piggy]

If all you mean by it is brain functioning, there's not a whole lot of mystery about why it evolved and why we expend the energy to maintain it.

Well, there is some debate about exactly why consciousness evolved and what precisely it does and doesn't do.

But we should be clear that "brain functioning" is not a sufficient definition of "consciousness" because we know beyond doubt that there is much brain functioning -- in fact, the bulk of it, from what we can currently tell -- which is not involved with the generation of conscious experience.

In fact, that distinction is fundamental to current brain research.

Many people seem to believe that there is something more to consciousness than a sequence of physical brain states, for example that it's not something a computer could possess (sorry Piggy). I don't think there is any evidence - or even any argument - for such a belief.

Well, sure, but since this thread is explicitly dedicated to a scientific approach, and to brain research, those opinions are not ones that we have to grapple with here, fortunately.

 

[sol invictus]

But we should be clear that "brain functioning" is not a sufficient definition of "consciousness" because we know beyond doubt that there is much brain functioning -- in fact, the bulk of it, from what we can currently tell -- which is not involved with the generation of conscious experience.

According to your definition from the OP: "Consciousness is what our brains are doing when we're awake, and when we're dreaming, which it is not doing when we're asleep and not dreaming or in a profound state of anesthesia."

Now, I'm not sure how you define dreaming. But I believe when people are in a profound state of anesthesia, their brains are doing very little other than basic physical processes (like blood flow)^*. If so, your definition of consciousness really is just "brain functioning".


^*Potential exceptions I'm aware include undergoing brain surgery, or possibly surgery involving the spinal cord or other parts of the nervous system.

 

[Piggy]

According to your definition from the OP: "Consciousness is what our brains are doing when we're awake, and when we're dreaming, which it is not doing when we're asleep and not dreaming or in a profound state of anesthesia."

Now, I'm not sure how you define dreaming. But I believe when people are in a profound state of anesthesia, their brains are doing very little other than basic physical processes (like blood flow)^*. If so, your definition of consciousness really is just "brain functioning".


^*Potential exceptions I'm aware include undergoing brain surgery, or possibly surgery involving the spinal cord or other parts of the nervous system.

No, you're viewing it wrong, but I have to say I'm not going to spend too much time on this.

Your brain is doing quite a lot while you're asleep and not dreaming. Perception, memory, learning, all that is still going on.

The difference is that set of functioning that's turned off when you're deeply asleep which is not turned off when you're alertly awake.

It's that particular function that we're speaking of.

Anyway, it's a functional definition, and I have to agree with Crick that "everyone has a rough idea of what is meant by being conscious. For now, it is better to avoid a precise definition of consciousness because of the dangers of premature definition. Until the problem is understood much better, any attempt at a formal definition is likely to be either misleading or overly restrictive, or both."

I am not going to get into a nit-picking argument over a precise definition, because it would be unproductive.

If you are genuinely flummoxed by what is meant by "being aware" or "being conscious" then this is not the thread for you.

 

[sol invictus]

No, you're viewing it wrong, but I have to say I'm not going to spend too much time on this.

As you wish.

Your brain is doing quite a lot while you're asleep and not dreaming. Perception, memory, learning, all that is still going on.

The difference is that set of functioning that's turned off when you're deeply asleep which is not turned off when you're alertly awake.

It's that particular function that we're speaking of.

Like I said, I'm not sure how you define "asleep and not dreaming". I think that's particularly problematic when you're trying to use it as part of the definition of consciousness. Your "profoundly anesthetized" was better - but then, your definition reduces to one you've already rejected ("brain functioning"). So at this point I have no idea where you're coming from.

I am not going to get into a nit-picking argument over a precise definition, because it would be unproductive.

Unfortunately, I think the lack of a definition simply leads to lots of arguments with very little content.

If you are genuinely flummoxed by what is meant by "being aware" or "being conscious" then this is not the thread for you.

I don't feel particularly flummoxed by what people mean by it - I just happen to think they vastly overestimate its significance.

 

[Roboramma]

Sol, do you agree that there are some aspects of what your brain is doing (even when you are awake) that are a part of conscious awareness and other aspects that are not?

The question asked by the OP seems to be "what is the difference between those two types of brain activity? and why are the former unlike the latter in this regard?"

 

[sol invictus]

Sol, do you agree that there are some aspects of what your brain is doing (even when you are awake) that are a part of conscious awareness and other aspects that are not?

Just about every process in your brain, if it stopped or changed dramatically, would affect your conscious awareness (measured by, let's say, self-report).

Let me turn it around - what experiment would you do and what evidence would need to result to demonstrate that a certain aspect of what your brain is doing is not part of conscious awareness?

The question asked by the OP seems to be "what is the difference between those two types of brain activity? and why are the former unlike the latter in this regard?"

Given a definition (so that there is a line between the two types) we can unambiguously discuss that. Without one, debates could go in circles forever (as usually happens in discussions of consciousness).

 

[MuDPhuD]

These people are blind. Impluses from their sensory apparatus cannot be transmitted to the areas of the brain responsible for conscious awareness. They have no awareness at all of anything they're seeing.

If you were in this state, you would certainly consider yourself blind.

Yes you (sofia) would, but your brain might not. Visual information from the retinas is received by multiple central targets in the human brain. The retino-thalamo-cortical pathway is considered to underlie conscious appreciation of visual stimuli. Bilateral damage to the occipital cortex alone will render sofia "blind", but the intact visual input to the superior colliculus, for example, will still enable the eyes to track a target, blinking to occur when the eye is threatened, or perhaps an emotional response to facial expression. Sofia will be unaware what is happening.
There is a large series of fascinating studies on a-callosal patients (severed corpus callosum) where objects shown to one side of the brain are not recognized/appreciated by the other. They are absolutely fascinating, and have direct bearing on what consciousness might be, and how it is related to brain activity. I'm sure Gazzangia mentions it. Oliver Sacks certainly does (Man who Mistook his wife for a Hat).

 

[yy2bggggs]

Just about every process in your brain, if it stopped or changed dramatically, would affect your conscious awareness (measured by, let's say, self-report).

Perhaps. But I think in this thread you should have to back this up by either citing experiments showing that it is indeed the case or arguing based on experiments that it is the case. Otherwise, you're doing philosophy, not "biological research perspectives".

Let me turn it around - what experiment would you do and what evidence would need to result to demonstrate that a certain aspect of what your brain is doing is not part of conscious awareness?

You would study whether or not that aspect of the brain had a correlation to self report of awareness of some particular thing. This can be done by performing various tricks with timing, interrupting that part of the brain, or any other tricks that neuroscientists run into while studying.

Given a definition (so that there is a line between the two types) we can unambiguously discuss that.

We don't have to unambiguously discuss it to discuss it, though. We have an object to study, and it's fruitful to simply study the behaviors of that object.

Without one, debates could go in circles forever (as usually happens in discussions of consciousness).

It doesn't have to be debated in this thread.

 

[sol invictus]

Perhaps. But I think in this thread you should have to back this up by either citing experiments showing that it is indeed the case or arguing based on experiments that it is the case.

I don't think I do - I think the burden of proof is on the other side. The null hypothesis should be that all brain processes are important for/part of conscious awareness (as measured by self-report) until otherwise demonstrated.

You would study whether or not that aspect of the brain had a correlation to self report of awareness of some particular thing. This can be done by performing various tricks with timing, interrupting that part of the brain, or any other tricks that neuroscientists run into while studying.

Great. Now it's time to post links to such studies .

 

[yy2bggggs]

I don't think I do

Then you're quite simply wrong. Of course you have a burden. The only way we're going to actually know that what you are saying is true is if there are experiments backing it up.

I think the burden of proof is on the other side.

What "other side"? This is not a debate thread. Presumably we're trying to figure out what is actually the case; i.e., our goal is to actually know something (and, again, the only way we're going to know it is to back it up with experiment).

The null hypothesis should be that all brain processes are important for/part of conscious awareness (as measured by self-report) until otherwise demonstrated.

This is an acceptable null hypothesis for the claim that the subset of the brain responsible for consciousness is a proper subset. But do not confuse a null hypothesis with a theory.

Great. Now it's time to post links to such studies .

The summary given by Crick in the link Beerina provided in post #15 describes experiments along these lines. In particular, it summarizes research into visual awareness, studying correlates of various aspects of visual perception to areas in the visual cortex, and correlates of the activity of those areas in the visual cortex to consciousness awareness as measured by self report.

As an example, he mentions studies of correlates of particular areas to recognizing orientation as measured by self report of gratings into the visual area, which are also reportable. Such areas react when visual masking is introduced sufficient to disrupt reports of conscious awareness, suggesting a relationship to the recognition of orientation and those areas of the visual cortex.

Such studies seem relevant to the discussion.

 

[MuDPhuD]

There are some Neuroscientists who believe that consciousness is amenable to study. Their basic supposition is that consciousness (awareness) is an emergent property of brain activity, that is, our conscious experience of life arises from the simultaneous activity of multiple brain areas in concert. Most of the brain's activity is not available to awareness (can never be called into consciousness); that is undeniable fact and I could digress into a very long description of why that is true if you want me to. The working neuroscientific model of consciousness is that networks of groups neurons, mostly in the cerebral cortex, acting as a unit, are responsible for constructing the image we see, the sounds we hear, etc.

Given the above premise, the goal of current experiments is to define which brain areas are active during "awareness". This involves surmounting two main hurdles.
1. localizing brain activity. This involves EEG and evoked potentials, positron emission tomography, functional MRI, or direct intracerebral electrical recording in awake subjects. You can see the obvious problem with the last, but the others all have attendant limitations.
2. You need an experimental paradigm which can compare conscious and unconscious states, with all other things being as equal as possible. That's also a tough nut to crack. Most of these experiments confound ATTENTION with AWARENESS, and indeed they may be inseparable.

Here is a summary tidbit of thoughts from Kouider and Dehaene, PhilTranRoySocB 2007 Vol362:857-875

"In this concluding section, we would like to argue that those results fit with the tripartite distinction of subliminal, preconscious and conscious processing that one of us has recently proposed (Dehaene et al. 2006). According to the global neuronal workspace theory, sensory information is consciously accessed whenever a bidirectional, self-sustained activation loop is estab- lished between the relevant posterior sensory processors and an assembly of workspace neurons with long-distance axons, distributed through the brain, but particularly dense in associative cortical areas, most notably prefrontal cortex (Dehaene et al. 1998, 2001, 2003). Thus, for a stimulus to reach consciousness, two factors are jointly needed: first, the input stimulus must have enough strength to cross a dynamic threshold for global reverberation (which can be prevented by stimulus degradation or competition with other stimuli, i.e. masking); and second, it must receive top-down amplification by distant neurons (which can be prevented by drawing these neurons into another stimulus or task). Accordingly, conscious access may fail for two quite distinct reasons, leading to a distinction between two types of non-conscious processes, which we call subliminal and preconscious, respectively (figure 3)."

A bidirectional self sustained activation loop...that's consciousness!

 

[Piggy]

I've got a good friend who work with smart power grids, and not too long ago we were talking about power lines.

If you've ever noticed, old lines were strung on poles vertically, one above the other. Newer lines are configured triangularly.

That's because the vertically arranged lines interfere with each other and put a drag on the power transmission. The triangular arrangement, on the other hand, syncs things up nicely and actually helps the flow.

So when you put power lines near each other, none of them is entirely independent, and what's going on inside of each depends on what's going on with the others.

Looking at research into mirror neuron systems in the human brain, and into the phenomenon of unconscious mimicry, has changed my view on what my brain is doing and how independent it can be.

As I mentioned before, our brains pick up on other people's emotional cues, and initiate unconscious physical mimicry of their bodies (unless we're competing against them or despise them), more quickly than our brains can do anything consciously. Not only that, but our processing of other people's emotional cues involves triggering, to some extent, those actual emotions in ourselves.

What this means is that when I'm around other folks, they are tweaking the state of my brain just by being around me, and there's nothing I can do about it.

I am a slightly different person, depending on the mixture of other brains whose activity my brain is capable of perceiving.

This also means that being a "social species" goes deeper than our typical vision of a bunch of individuals who have learned to get along. It means that our brains are built to interfere and cooperate with each other merely by virtue of being nearby.

Our brains are continually readjusting themselves, on their own, depending on their positions relative to each other.

 

[Piggy]

A bidirectional self sustained activation loop...that's consciousness!

Thanks for the citation.

One comment, tho.... We have to be careful how we phrase our conclusions.

I would say that, if this view is accurate, consciousness is a bi-directional self-sustained activation loop.

But this is not the same as saying that a a bi-directional self-sustained activation loop is consciousness. The latter implies that we would get consciousness from any system of that type, and we don't know nearly enough to conclude that, even if we assume the paper is correct.

 

[Piggy]

Unfortunately, I think the lack of a definition simply leads to lots of arguments with very little content.

True, which is one of the primary reasons I provided a stipulative definition for the purposes of this thread.

I'm confident that reasonable people will have little trouble understanding what that definition is referring to.

It is not meant to be a final and complete definition of the phenomenon of consciousness, only to point to what it is we're talking about, and to exclude other definitions that fall outside the scope of the thread.

 

[Piggy]

Given a definition (so that there is a line between the two types) we can unambiguously discuss that.

The purpose of this thread is to discuss biological research on the brain and how the brain produces conscious awareness, in an environment in which even the researchers agree that a precise definition of the term is not yet available.

I'm sure that we can do just that given the stipulations in the OP.

Is there any brain research you particularly want to discuss?