More on the Elusive NCC

Earlier this month I discussed the difficulty of finding the NCC, the neural correlates of consciousness. It is extremely hard to know which aspects of a brain’s activity constitute (or generate) conscious processes and which are the unconscious accompaniments of our conscious experiences. Those who are interested in this problem may want to read “Why the Neural Correlates of Consciousness Cannot be Found,” by Bernard Molyneux (Journal of Consciousness Studies, No. 9–10, 2010).

Molyneux asks whether we can discover “the perfect correlate of consciousness – the neural events that occur, in both normal and abnormal circumstances, when and only when consciousness is present. However, consciousness correlates not only with the NCC but also with its causes, its consequences and with other associated states. Hence, to determine the true NCC, we need to drive these states apart to see which one consciousness tracks, by holding one constant while obliterating its usual correlates”(p. 169). I don’t think we need to “obliterate” any brain states to study consciousness, but I agree with Molyneux that it is very hard “to distinguish the ‘one true’ NCC from closely associated phenomena” (p. 169).

I’m not ready to give up on finding the NCC. So many times in the history of science some pundit has declared that we will never be able to discover such-and-such, and 50 years later we do. And Molyneux does seem to admit that there’s a ray of hope: “… the problem demands a greater appreciation of when a seeming dispute between NCC researchers cannot be empirically settled, and calls for a more perfect philosophical explication of what exactly it is that we can hope to find when we set out to look for the (rather than a) neural correlate of consciousness” (p. 169). Very true, and this is an example of the practical relevance of philosophy.

Roger Christan Schriner


Returning to Consciousness

I’m returning to this blog after taking several weeks off. Ironically, I stopped writing posts because I was too busy working on a book about consciousness, Your Living Mind: The Mystery of Consciousness and Why It Matters to You. The book should be out this summer.

In my last post I talked about the debate between externalists and internalists. When we speak of conscious experiences, are we talking about our own states of mind or are we talking about things in the outside world that we’re consciously perceiving?

And could it be both? Could one and the same experience tell us about both the outside world and our own minds? Obviously it’s possible to detect two or more things by focusing on the same item. Think about a TV newscast. By watching it, you are monitoring (1) its content (what it’s telling you about world affairs), (2) the screen images which help convey this content, and (3) with old low-resolution TVs, the dotty little pixels that make up these images.

So a single stream of stimuli can tell us about several different things. Could it be that a multiple-detection process of some sort is occurring in consciousness? Perhaps sensory experiences are in some sense both inner and outer states (or processes). Even so, we run into trouble if we use this approach to answer the basic question, what are conscious experiences made of? Contrast these two claims:

❁ Seeing a giraffe gives me information about both what’s happening inside of my head and what’s happening in the outside world. I can tell that I am perceiving this animal in a certain way (seeing it clearly or fuzzily, for example), and I can also tell that there’s a giraffe in front of me.
❁ The stuff that I detect when I pay attention to the experience of seeing a giraffe is both the giraffe itself and a visual experience of that beast.

The second claim, which says what this experience is, just sounds silly. Tall spotted creatures and mental events in human heads are very different kinds of things. How could one thing actually be both of these? Compare: “I now see a red shape on my TV screen. This shape is both a screen image of a fire truck and the fire truck itself.” It seems more fitting to say that I’m seeing a screen image which I imaginatively experience as a fire truck.

If this tall creature I see IS both a visual state and a humongous mammal, we must be dealing with two different senses of “is.” So in what ways could this experience be something inside of the experiencer, and in what ways could it be something out there in the world? What do you think?

Roger Christan Schriner

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What is Consciousness?

Many authors have said that precisely defining consciousness is impossible, and they may well be right. But as I begin posting entries on this blog I should indicate what I mean by human consciousness. As a rough overview, I suggest that typical human conscious experiences have the following five characteristics.

1. Our experiences are available for use by the mind’s master control centers. That’s why consciousness is sometimes called a global workspace. During our waking hours we deal with all sorts of challenges, like managing to walk down the street without tumbling heels-over-head on a banana peel. To survive these challenges, our perceptions must be available to the mental mechanisms that form beliefs, think, feel emotions, make decisions, and instigate actions. If you are wrapped in a warm embrace, for example, you would typically believe you’re in an embrace, have thoughts about it, respond emotionally, make choices, (keep hugging, or disengage?), and use the experience to guide your actions.

2. You are one who has your experiences. I can’t tune in to what’s in your head the way you can. (Some would disagree with this claim, but I think it’s true.) So for one of your mental events to be conscious it must be conscious to you as an experiencing self.

But what is a self? Answering that question is about as hard as defining consciousness. What’s important for our purposes is that some part of us registers, enjoys, and suffers our own experiences. We do not yet have a clear and agreed-upon understanding of this experiencer. It may be a single brain system or a team of systems working together. The exact nature of this system or systems is not crucial for our purposes.

One big difference between persons and non-conscious things such as rocks is that something within us “gets” our experiences. Suppose we figured out that some specific pattern of brain activity is absolutely identical to the way you feel when someone tickles your feet. Even if we managed to completely and precisely transplant that neural activity pattern into the middle of a boulder, and keep it alive and functioning, the rock would not feel any urge to giggle. Why? Because nothing in the rock is equipped to experience the ticklish sensation. The sensation just sits there, unknown and unappreciated.

3. Experiences are typically remembered, at least briefly. (Experts disagree about whether all details of experience are held in short-term memory.)

4. Under normal circumstances at least some aspects of an experience are reportable, although our reports are often vague. One can say, “I saw that tree blowing in the wind,” without being able to specify which leaves and branches appeared to be jiggling.

It is quite remarkable that through some obscure mental mechanism we can speak about our own states of mind. If I think about what to eat for dinner or I feel a sharp twinge in my toe, I may find myself reporting these inner states in comprehensible English. We have hardly a clue how that happens.

5. Some of our experiences, especially physical sensations and sensory perceptions, seem “present.” Philosophers find it especially difficult to explain how brain activities could generate a sense of presence, so I’ll consider this point in more detail later.

What do you think of this list? Do these items roughly indicate what scholars mean when they speak of introspectable experiences and conscious phenomena? Would you add or delete items? I welcome your comments.

Roger Christan Schriner

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