How the Brain Does Consciousness: Biological Research Perspectives

[Piggy]

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).

Correct, which is why such research is so interesting, and also why it's relevant to this thread.

The point of citing the research on folks with certain types of blindness and their ability to discern emotions from faces they are not (and cannot be) aware of seeing is to elucidate some of the internal operations of the brain.

I'm not at all interested in discussing how we define the word "blind"... clearly, these folks are functionally blind in the everyday use of the term.

 

[Piggy]

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.

That is not a proper scientific perspective. There is no "null hypothesis" on this count, going in to biological research. Nor is there any need to create one.

The purpose of the research is to determine what's going on, and we do this without siding with one assumption or another from the get-go.

Anyway, if there's actual research you'd like to discuss, then by all means, bring it into the discussion.

 

[Dymanic]

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

Excrementitious polysyllabic terminological esoterica... that's word salad!

 

[MuDPhuD]

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.

Point taken, that last line was tongue-in-cheek, and I would certainly not assume the conclusions of this paper are correct. They're trying, and they're among the very few with the tools and know how to address the issue, but I think they're still a long way from nailing it down. Its a fascinating field, but fraught with difficulties as I alluded to previously.

 

[Piggy]

Since the boundaries of consciousness were mentioned earlier, here's a study on that point from October.

This Is Your Brain on Anesthesia: New Light Shed on How Brain Reacts During Anesthetic Induction and Emergence

They studied brain activity as folks were knocked out by anesthesia and as they woke up.

Losing consciousness under those conditions was characterized by a large-scale disruption of the impulse-flow, "a sudden structural disruption of brain networks", in some regions such as the parietal, but not in all (e.g. not in the frontal).

But waking up was characterized by a weak re-establishment of the impulse pattern, followed by a rapid build-up in connection strength.

Sounds kind of like how the fluorescent bulbs work in my overhead lamps.

Here's another from 2004:

Study Reveals Cause Of Loss Of Consciousness During Seizures

A different scenario, but once again we've got disruption of large-scale impulse patterns:

The study found that in patients who lost consciousness during seizures, there were abnormal signals scattered across brain images like a fireworks display. In contrast, patients who had seizures but did not lose consciousness had localized increases confined to the temporal lobe.

Nothing in that one about how things looked when folks regained consciousness.

 

[Zeph]

What's surprising, in fact, is the range of ability of the non-conscious modules, which can perceive, remember, act, and even learn.

In attempting to sort out (small) chunks of the subject...

Is there a real distinction between non-conscious "remembering" and "learning"? We can demonstrate that non-conscious modules can retain imprints from past experience because, for example, their reactions to stimuli can change based on that experience (despite the conscious mind being unaware of that experience). Is that a case of demonstrated learning (in the general sense) implying some memory of what was learned?

Can we demonstrate learning without memory, or memory without learning, from non-conscious modules? Is there a distinction?

Another question: you wish to distinguish the brain states of wakefulness and some forms of sleep (REM?) as conscious, from the rest. Is there any research on which non-conscious modules are fully operating and which are not, between these states?

And finally - consciousness is probably not a binary question. Subjectively there seem to be degrees of consciousness - one may be half awake, or groggy from anesthesia, or just beginning to create full consciousness as an infant. It would be interesting to look for brain correllates variations along a spectrum of consciousness. [Edit - finishing the thread I see a reference to studies of patients trasitioning between full consciousness and anesthesia, very much in this direction of investigation]

 

[Zeph]

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?

Off the cuff: Assess unconscious posture mimicry to see if people adopt similar, different or uncorrelated postures and "body language" to those they are communicating with in person, without self-reported awareness thereof.

Measure pupil diameter in response to stimuli of which the subject appears to be consciously unaware.

Measure vaginal secretions and engorgement in response to visual stimuli which are reported as distinctly non-sexual.

Measure political liberal/conservative spectrum questionnaire responses after exposure to very brief visual stimuli associated with dangerous vs neutral images which by self-report were not consciously seen nor self-perceived to have any effect. (This is of a different nature of course, as it relates to modified cognitive function rather than unconscious body reactions).

Measure whether heartbeat or other physiological measures can be affected by subtle odors of which the subject is consciously unaware.

Of course, your term "part of consciousness" is kind of vague, so there might need to be a more clear definition of what "part of" means. Does it mean that it's accessible to self-report as part of subjective consciousness, or merely that activities traditionally imagined to be based on conscious decision making have been influenced measurably without being in any way accessible to self report? (For example, consider questionnaire responses in which the subject is consciously aware of which choices they objectively made, but not necessarily of what influenced those choices - would those influences be defined as "part of" consciousness if they influence in any way actions of which one becomes conscious?)

 

[sol invictus]

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.

My current hypothesis is that there is no useful distinction between "consciousness" and "normal brain functioning"; that is, that this big mysterious thing we call consciousness is nothing more or less than the sum of all the various interactions going on in our brains. That hypothesis could be proven wrong by (for example) experiments showing that certain aspects of normal brain function can be seriously disrupted without affecting consciousness (as defined/measured by self-report, simply because I don't know how else to define it). Then we could say that those aspects of brain function are not part of consciousness.

I think it's useful to start from a position like that and attempt to falsify it. If it cannot be falsified despite repeated attempts, it's an indication that it might be true. If it's true, it means many of the question raised in this thread ("why did consciousness evolve?") have rather obvious answers, and that one should shift one's focus from such meaningless questions towards more specific and interesting ones ("what is the aspect of brain function responsible for recognizing faces?").

Even if it's not literally true in the strictest sense (and it can't be - sufficiently tiny changes in the brain aren't going to be self-reportable), finding its limits would teach us a lot about how useful a concept "consciousness" really is.

The summary given by Crick in the link Beerina provided in post #15 describes experiments along these lines.

Crick asserts that to be aware of something, say an aspect of a face, there should be a localized collection of 1,000 neurons or so somewhere in the brain that form a representation of that aspect of the face. He says that if those neurons were destroyed, the subject would cease to be aware of that aspect. That perhaps defines what it means to be conscious of something, but it's a very long way from addressing the question of whether there is a distinction between consciousness in general and the set of all normal brain functions. It simply identifies a specific aspect of normal brain function and identifies it with a specific external stimulus.

 

[Beelzebuddy]

If I might take a whack at this knot, I would propose discarding the term "consciousness" entirely. It's one of the most loaded terms in the english language. Everyone knows what it means, and expects everyone else to use their definition, so any discussion inevitably succumbs to bitchy semantics. If I wanted that I'd go throw more crap at rramjet in the skeptics forum.

Furthermore, there are a number of different meanings all of which use the term. Is "consciousness" self-consciousness? Being conscious? Being conscious OF something?

And whenever anyone sits down to set a definition, there's always a better description of what it means. Take yours, Piggy. "A state of wakefulness or REM sleep" suits your definition far more accurately than calling that consciousness. Hell it IS your definition, so I'm not exactly sure what more you want, there.

Ultimately, no one has found any indication of anything we call "consciousness" in the brain. Some of its components maybe. Attention, that's a real biological thing. Self-awareness, there's bits of brain that seem to relate to that. Memory, well, memory probably plays a much bigger role than most people realize. When you do something and don't remember it, people tend to call that "unconscious' or "subconscious" action, when in fact it was just your episodic memory not giving a crap about this particular commute or brushing of your teeth. Doesn't mean you weren't "conscious" while you were doing it.

It's just a bad, bad term, made worse over the years by generations of armchair philosophers, crank psychologists, and college sophomores, who have ideas which make, like, total sense to them despite not having any rooting in actual biology.

 

[bobc]

I also strongly suspect that conciousness does not exist as a discrete entity within the brain, and it is mostly likely that certain activity patterns will be associated with conciousness, i.e. it is an emergent property. I also think there are degrees of conciousness. Oliver Sachs writings are interesting, on what happens to self-awareness when various brain functions are impaired, as well as how people with impairments are viewed as self-aware beings.

Clearly (to me), a high level conciousness such as humans have must have evolved from non-self awareness through various degrees of awareness. A lot of other animals show signs of self awareness, but not to the level of humans.

Since conciousness is such a fuzzy ill defined concept, it is probably better that we do not attempt to define it, but just study it. Not having overall concepts well defined has never stopped scientific study in the past. It is more a problem for philosophers who ask "what does it mean?".

 

[Dymanic]

Not having overall concepts well defined has never stopped scientific study in the past.

For example...?

 

[rocketdodger]

What has affected me the most so far as a result of this reading is coming to terms with an idea I was already aware of intellectually, but which now occupies my thoughts throughout much of the day: Everything I'm aware of is already over.

This is a quite profound realization that goes right to the heart of who I think I am.

This isn't unique to consciousness in our brains piggy, it is a fact of existence -- cause and effect.

Logically, the effects of X must be preceded by X.

 

[rocketdodger]

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 making the same mistake all the "hard problem of consciousness" folks make -- there is no evidence, nor any rational reason for why there would be evidence, that sofia is doing anything above and beyond sofia.

I can see why an entity with sofia would have many advantages over one without sofia. All of those are due to sofia.

So what is the issue?

 

[rocketdodger]

My current hypothesis is that there is no useful distinction between "consciousness" and "normal brain functioning"; that is, that this big mysterious thing we call consciousness is nothing more or less than the sum of all the various interactions going on in our brains.

This gets back to the whole p-zombie thing.

Piggy is setting this discussion of his up for failure by simultaneously proclaiming that there shall be no talk of anything but actual research AND throwing around vague terms like "consciousness" -- hey, we all *know* what consciousness means, right?

No, we don't, actually.

If you want to talk actual science, then you have to talk actual science. That means instead of asking "where does consciousness come from" you have to ask things like "what is going on in our neural networks when we see a face and recognize it?"

And when questions are framed like that, guess what? "Consciousness" reduces to "normal brain functioning." How do we recognize a face? Here is what is going on in the neural network -- there, done. Question answered.

Or, more to the point, where does sofia come from? Well, first, try defining sofia in terms that are scientifically accessible. Has that even been done? Piggy?

Crick asserts that to be aware of something, say an aspect of a face, there should be a localized collection of 1,000 neurons or so somewhere in the brain that form a representation of that aspect of the face. He says that if those neurons were destroyed, the subject would cease to be aware of that aspect. That perhaps defines what it means to be conscious of something, but it's a very long way from addressing the question of whether there is a distinction between consciousness in general and the set of all normal brain functions. It simply identifies a specific aspect of normal brain function and identifies it with a specific external stimulus.

This is always going to be a problem in these discussions -- we could plot out the topography of every network involved in facial recognition, and show it to the person recognizing the face, and say "look, this is what your neurons are doing" and still they are going to ask (unless they know better) "but ... I don't understand where the feeling of recognition comes from ... those are just neurons, where does the rest come from?"

People are always going to ask why pain feels like pain instead of something else. Telling them that pain feels bad because it evolved so creatures would avoid it isn't good enough.

Where does that "feeling" come from, man?

 

[rocketdodger]

Not having overall concepts well defined has never stopped scientific study in the past.

I am going to give you the benefit of the doubt and assume you mean "not having overall concepts well defined has never stopped the scientific study of specific aspects of those concepts, which of course must be defined -- you can only study something to the extent that is defined."

 

[Piggy]

In attempting to sort out (small) chunks of the subject...

Is there a real distinction between non-conscious "remembering" and "learning"? We can demonstrate that non-conscious modules can retain imprints from past experience because, for example, their reactions to stimuli can change based on that experience (despite the conscious mind being unaware of that experience). Is that a case of demonstrated learning (in the general sense) implying some memory of what was learned?

Can we demonstrate learning without memory, or memory without learning, from non-conscious modules? Is there a distinction?

I'm not familiar with the whole body of publishing by any means (which is one of the reasons I started this thread, to read more stuff) but from what I've seen, the answer is yes and no.

No, I haven't seen anyone claim to know if there's a sharp boundary or what the boundary, sharp or not, might look like.

But yes, I've read about studies that distinguish between the different types of learning, and identify at least some of the differences in brain resources used in them.

The use of memory is implicit in all of these studies.

Here's one from last year, regarding possible shared apparatus between humans and other / extinct species for non-conscious learning.

Unconscious Learning Uses Old Parts of the Brain

Here's another one from 2008 which demonstrated that people could learn to play a game better, for money, based on exposure to signals that they have no conscious awareness of at all.

Subliminal Learning Demonstrated In Human Brain

Dr. Pessiglione and colleagues created visual cues from scrambled, novel, abstract symbols. Visual awareness was assessed by displaying two of the masked cues and asking subjects if they perceived any difference. "We reasoned that if subjects were unable to correctly perceive any difference between the masked cues, then they were also unable to build conscious representations of cue-outcome associations," explains Dr. Pessiglione.

In the next set of experiments, subjects performed a subliminal conditioning task that employed the same masking procedure, but the cues were now paired with monetary outcomes. Using this methodology, the researchers observed that pairing rewards and punishments guided behavioral responses and even conditioned preferences for abstract cues that subjects could not consciously see.

The researchers collected scans of the brain, using functional magnetic resonance imaging, to investigate the specific brain circuitry that is linked to subliminal instrumental conditioning. "The ventral striatum responded to subliminal cues and to visible outcomes in a manner that closely approximates our computational algorithm, expressing reward expected values and prediction errors," says Dr. Pessiglione. "We conclude that, even without conscious processing of contextual cues, our brain can learn their reward value and use them to provide a bias on decision making."

Gazzaniga writes about this, too, in Human.

Another question: you wish to distinguish the brain states of wakefulness and some forms of sleep (REM?) as conscious, from the rest. Is there any research on which non-conscious modules are fully operating and which are not, between these states?

I'm not seeing anyone using that kind of framework, actually. I mean in terms of a consciousness that's "fully operating" or not.

Dreams have been identified in REM and non-REM sleep, and they may serve different purposes, btw.

During dreams, some bodily functions are altered or disconnected from interacting with the modules taking care of conscious awareness (e.g., we're paralyzed so we don't act out our dreams, and folks whose apparatus has broken down... they're hard to share a bed with).

And the brain's not acting in exactly the same way during these different states.

It's not the same conscious state as waking consciousness is, but the basic functionality is there. Ditto for some drug-induced brain states.

As I understand it, it's rather difficult right now to get people into a whole lot of natural brain states while at the same time peering deeply into the workings of their brains, so our understanding is understandably limited.

And finally - consciousness is probably not a binary question. Subjectively there seem to be degrees of consciousness - one may be half awake, or groggy from anesthesia, or just beginning to create full consciousness as an infant. It would be interesting to look for brain correllates variations along a spectrum of consciousness. [Edit - finishing the thread I see a reference to studies of patients trasitioning between full consciousness and anesthesia, very much in this direction of investigation]

Yeah, there are some folks working on high-focus/high-attention states, others working on dream states, some focusing on the borders of conscious perception, even seizure states.

It's an interesting time.

 

[Piggy]

If I might take a whack at this knot, I would propose discarding the term "consciousness" entirely.

Be my guest, but please, if you do, do it on some other thread, if you don't mind.

This particular thread is about brain research and consciousness. It's just got to be that way, or else we're going to get on endless tangents.

Sorry, but I've seen it. Thanks.

 

[Piggy]

I also strongly suspect that conciousness does not exist as a discrete entity within the brain, and it is mostly likely that certain activity patterns will be associated with conciousness, i.e. it is an emergent property. I also think there are degrees of conciousness. Oliver Sachs writings are interesting, on what happens to self-awareness when various brain functions are impaired, as well as how people with impairments are viewed as self-aware beings.

Clearly (to me), a high level conciousness such as humans have must have evolved from non-self awareness through various degrees of awareness. A lot of other animals show signs of self awareness, but not to the level of humans.

Since conciousness is such a fuzzy ill defined concept, it is probably better that we do not attempt to define it, but just study it. Not having overall concepts well defined has never stopped scientific study in the past. It is more a problem for philosophers who ask "what does it mean?".

Taking the point backwards,....

I have to say that there's no doubt the philosophers will have their way with the term until scientists do the work of figuring out more precisely what it means. That's how it always works.

And it looks more and more at every turn that consciousness is indeed a discreet function, or as discreet as any brain function can be (which is limited) rather than a truly "emergent property", such as the whiteness of clouds.

We've seen a high level of "choice", so to speak, regarding whether any particular input is allowed to be routed over to areas handling conscious awareness, and a great deal of flexibility by the brain when it comes to involving consciousness in tasks that don't absolutely require it.

We can also see signals bifurcating to areas that handle conscious awareness and other areas of the brain simultaneously, as revealed in the "blind" face recognition studies and "blind sight" maze experiments.

There is also pain blindness, and emotional blindness.

The more we delve into the brain, the more clearly it appears that consciousness is one of many semi-discreet functions of the brain (why should we expect anything else?) and the less it appears that it is a true emergent property or a "side effect".

 

[Piggy]

This isn't unique to consciousness in our brains piggy, it is a fact of existence -- cause and effect.

Logically, the effects of X must be preceded by X.

Exactly. Our brains behave like everything else.

 

[Beelzebuddy]

Be my guest, but please, if you do, do it on some other thread, if you don't mind.

This particular thread is about brain research and consciousness. It's just got to be that way, or else we're going to get on endless tangents.

Sorry, but I've seen it. Thanks.

I was politely calling the whole thing crap, actually. Biological research regarding consciousness is a bit like physics research regarding the luminiferous aether. The reason there hasn't been much research on the topic is because it just doesn't exist, but scientific literature is far too polite to say so in even as veiled a fashion as I did.