The Neuroscience of Consciousness: From Cells to Self

One thing that struck me as odd during our conversation last week was the idea that consciousness is a matter of complexity of neural connections as well as reproducibility.  Although this seems to make sense initially, it seems oddly reminiscent of how we determine intellect and learning.  We say that learning is the process of forming strong synaptic connections (long term potentiation); thus, it logically follows that a more intelligent person will have more complex and strongly formed synapses (assuming that you agree that learning is a key component of intelligence).  This seems like a flaw in the theory; are we really saying that consciousness is equated with intelligence?  Perhaps to some degree this is true – a human is more intelligent than a fly and most people would agree that the human is more conscious as well (although we don’t really know this).  However, I would argue that consciousness in human adults is not correlated with intellect, and I feel that it is dangerous to draw a connection between consciousness and intellect in this way.  The phi value (info & connections) seems to be missing a key component – I’m just not sure what.

            Bo-Rin’s comment about the possibility that there are more than “two clear cut categories of consciousness and unconsciousness” made me think about a discussion I recently had with some of my friends.  Sometimes when I am just waking up, I see something that doesn’t exist (like a person) within the context of the “real world” (what actually exists around me).  I’m not sure if this is a common phenomenon (my friends seemed to think I was weird, so maybe not), but it made me wonder what state of consciousness this would be classified under.  I am consciousness when it occurs – as I experience the “real world” around me – but my brain simultaneously conjures a false image.  If consciousness involves experiencing "real" sensations from the surrounding world, then am I really conscious when this occurs?

Some thoughts from this week's discussion relevant to our next conversations on imaging and anxiety: 
I am really intrigued by this potential ability/ evolutionary advantage of being able to turn on and off our own consciousness ... EB Ver Hoeve
What does our brain do to make us go from one state to the other? Is there a physical difference between an unconscious and conscious brain (I’m sure there is—I just don’t know exactly what the difference is)? ... Bo-Rin Kim
"it is not as easy as putting someone in an fMRI and providing them with a consciousness-relevant task to create an image of the neural map of consciousness.  That does not mean, however, that such a map does not exist" ... Jeremy Posner
Without the knowledge of unconsciousness, it seems hard to acknowledge one's own consciousness ... aliss
I was sort of skeptical of the topic of consciousness in general- at least approaching it from a scientific side ... After some thought, however, I think that is very useful to understand consciousness in cases of extreme head injury  .... sberman
and, perhaps, depression, and anxiety, and ... ?  Its interesting, perhaps significant, that a group of NBS seniors would be so skeptical about "consciouness" as a part of brain/behavior  ... PG

Thanks all.  Interesting conversation both last Monday night and in followups here.  I'm inclined to agree with Jeremy that "everything that is necessary to understand human behavior (in a sense) is available to us through the study of the nervous system and its interactions within the body,"  that "All of the components of consciousness are simple processes," and that "if a mechanical consciousness is created it will be the result of replicating the structure of a working consciousness."  Like Bobby, I'm less sure that "continued development of imaging technologies" will make that possible.  I can see all parts of a functioning engine and still have no idea of how it works.  The latter depends as well on, among other things, knowing what function the engine serves in the larger context of which it is a part.

I also agree with Vadilson and others that "Consciousness is a difficult topic to pin down."  My guess is it will turn out in the long run that the difficulty is a consequence of using the same term in a variety of different ways (cf Sara on conscious, subconscious, and unconscious and Alison on "presence in the moment and attention," and "simply being awake and alert ... and responding to one's surroundings."  My own inclination is that we need to focus a bit more on particular things that we want to account for and let the definition of consciousness evolve from that rather than arguing about what is or is not "conscious."   Yes, I think plants don't have it.  Whether societies do or don't is an interesting question but one that ought to wait until we have a clearer sense of what we want to account for in cases where we're surer of what we're exploring.

The upshot, for me, is to be inclined to focus for the moment on humans and on the pretty straightforward observations that human behavior can occur without any internal awareness of one's self and one's behavior or with such an awareness.  If we take the latter as an operational definition of "consciousness," some interesting things follow from it.  Among them is that consciousness (in this sense) is neither dependent on language (contra David) nor simply a function of neuronal number/complexity (see Megan).   We can have awareness without language and, given a nervous system of (at any given time) constant neuronal number/complexity, we can switch between unconscious and conscious function.

Two other interesting things that follow from this line of approach are a recognition that we don't need "consciousness" for most of our behavior and that we can be "conscious" without behaving in the sense of reacting to the world around us (thinking and dreaming both involve an active awareness of self).  And from that comes what I think is an important question that may help get a better handle on the context within which consciousness needs to be explored. 

Consciousness is not synomous, for humans, with either being alive or behaving.  We can do both without it.  It seems to be an additional capability, one we have in addition to being able to live and behave.  It is in this context that I think we can ask some further questions about consciousness that might be productive: what is the function of consciousness?  what does it make it possible to do that we can't do without it?   why do we switch between conscious and unconscious states?  what aspects of human behavior/experience wouldn't exist if we we're conscious?

I'm intrigued by the notion that neither pain nor disability (among other things) would exist without consciousness.  And by the idea, connecting to our earlier discussions, that depression as a human phenomenon and the contagion of mental illness diagnoses might not exist either.  Perhaps if we better understood what's involved in these sorts of phenomena (as well as a number of more positive versions of them), we might better understand the function consciousness serves in the larger context of the nervous system and human behavior/experience, and that in turn might give us a way to better interpret observations on the nervous system itself, and suggest new ones that should be made.       

Consciousness is a conceptual (and semantic) problem, but is is also a practical one (as per vgopinath), and one we have all kinds of experiences with in our day to day lives.   Perhaps more attention to its down to earth and practical manifestations would contribute significantly to clarifying the conceptual and semantic issues (cf The role of story in mental illness)?

As David has already put in great thank you for the participation in Monday’s class. Consciousness is a difficult topic to pin down and even in David and my research to find articles for the discussion, we found ourselves looking at articles for self-consciousness and elephants.  At this point we had to really specify what we would be talking about for class. In class we really came along in our personal definition of what consciousness could be and we also came to a lot of road blocks with the idea that in certain people there might be many wholes in one whole (remember Paul’s comment). 

The CNN video was also one that was very intriguing because it sheds new light in the ability to communicate to people that were diagnosed to be brain dead yet they seem to understand us and respond. Many would argue that if this is possible than those people are conscious and thus our definition of being brain dead has changed since a person that is “brain-dead” surely can not be conscious. Everyday the world of science is learning new things and contradicting or correcting itself, it is because of this that we keep an open mind to all new things.    

 Consciousness is such a great and terrible discussion.  As a phenomena, consciousness is captivating, the source of awareness of all other phenomena, and at the same time so poorly understood or even defined.  We are not only unable to find it, we are unsure of what exactly we are looking for.

Our discussion of consciousness yesterday really got me thinking about the nature of consciousness.  We wouldn't even be having this conversation if not for the fact that we were conscious.  We can tell that our dogs and cats are conscious, we're pretty sure that our fish are conscious (goldfish have a memory of 5 seconds, right?), but are plants conscious?  Is a computer conscious?  My immediate answer would be "no."  But then, what is consciousness?  We described two types of consciousness yesterday.
The first type of consciousness we discussed is presence in the moment and attention.  I think this type of consciousness can be related to (but not equated to) theory of mind.  Theory of mind is something that human beings develop as toddlers - the idea that other people have consciousness that is separate from one's own, and that other people are intelligent.  Higher primates have also been shown to have theory of mind (a hallmark of which is the ability to recognize oneself in a mirror and not think another person is staring back).  Theory of mind in humans seems to develop alongside language and the knowledge of mortality.  These could be coincidences, but I don't believe they are.  As David mentioned, language is an integral part of consciousness.  If you don't have the words to describe your state or your existence, how can you conceive of the fact that you exist?  Recognition of mortality is akin to recognizing the possibility of unconsciousness.  Without the knowledge of unconsciousness, it seems hard to acknowledge one's own consciousness.
Then, we also discussed the other type of consciousness: simply being awake and alert rather than asleep, and responding to one's surroundings.  In this case, the line of consciousness seems harder to define.  Plants react to their surroundings - the grow towards light and grow more when they are exposed to classical music.  Are they awake as opposed to asleep?  That is harder to say.  However, I think that the response to one's surroundings is an important aspect of consciousness that we didn't discuss in class.  In this line of thinking, plants and individual cells are conscious.  I don't believe that plants have the same experience as a human being might have.  However, defining consciousness might require expanding our definitions of what is conscious.

     One question David brought up in class yesterday that I have been thinking about is the number of neurons we can replace with electrical chips and still consider the person to be conscious.  Even if these new chips do not have the same plasticity as a neuron and just connect the two nerves/areas of the brain the replaced neuron connected, I would consider the person to be conscious.  Personally, it's difficult for me to consider determining that a human being, especially someone talking, walking, reading and doing arithmetic, lacks consciousness.  Yet those are all skills a computer has.  Perhaps an aspect of consciousness that I had initially not considered is whether or not that entity ever had agreed-upon consciousness and if we, as society, are "giving" or "revoking" consciousness in making a decision.

     A person who is inarguably conscious and sustains serious trauma to the head may no longer fit into our definitions of consciousness but because the person was conscious, when basic capabilities are left, we don't want to take their consciousness from them.  Synergy and connections between information are critical to consciousness but, as we discussed yesterday, split brain patients are considered to be conscious yet they do not have a corpus callosum to connect the hemispheres of their brain.  They lack the connectivity we deemed crucial.  Similarly, a computer in which we can input information but no new information can be stored would not be considered nearing consciousness.  This computer does not have the ability to retain new information and respond to its environment in a long-term fashion.  A person who has anterograde amnesia and can no longer form new memories nor remember reactions and details about the environment is similar to that computer.  Yet that person has a history and was undoubtedly conscious.  Therefore, because we can't conclusively and decisively determine what consciousness is, we don't want to inadvertently define it by revoking consciousness for people who sustain certain injuries.  Society has difficulty giving consciousness to a machine or something that we haven't already agreed is a conscious entity and we also have difficulty revoking consciousness from an entity society has agreed is conscious.  When we are arguing about consciousness, I believe that most of us are subconsciously trying to maintain the status quo and prevent other animals/ machines from being conscious while preserving it in humans, even babies (who lack language and an internal dialogue) and individuals with brian injury.