Happy Mortal

This life, well-lived.

Blind Man Sees

Painted Eye

TN, a middle-aged man from Switzerland suffered two strokes several years ago. The strokes caused extreme damage to his visual cortex, the part of the brain primarily responsible for vision. The catch? He can still see. Not Exactly Rocket Science reports that under certain circumstances TN has been able to accurately identify the emotions playing across people’s faces and also indicate which direction a metal bar was pointing (horizontal, vertical, or diagonal).

But TN caused the biggest brouhaha when he completed an obstacle course (you can watch the video here). Scientists were astounded when TN successfully navigated a length of hallway littered with stands, books, files, and boxes, without touching a single object. The only person who remained unperturbed was TN. For, TN’s condition, “blind sight”, allows him to “see” certain things without the awareness that he is seeing them. In other words, he sees unconsciously. So after he made his way down the hall, he had no idea that he had avoided numerous obstacles.

NPR notes that scientists will use TN’s case to study consciousness. They can compare the way TN’s brain works when he unconsciously sees to the way a person’s brain works when s/he consciously sees. By analyzing the difference they hope to learn more about how consciousness arises and how it functions.

TN’s blind sight raises questions about the centrality of consciousness and the unity of the homo sapien. Am I an unsteady alliance of bio-machines that has a particular part (consciousness) that makes me think I am one? What is your take on TN and consciousness?


  1. Crazy. Now I can say, ‘my unconscious sight made me do it.’

  2. That is out of this world fascinating! The arrogance of the consciousness has long been intriguing to me, and I have recently been trying to cultivate a growing respect for how much more my mind knows than I do. Certainly TN’s situation takes this concept to a particularly brilliant extreme.

    So in addition to the known knowns, the known unknowns, and the unknown unknowns, we can add the unknown knowns.

    A friend recently likened relying solely on the conscious awareness to using a flashlight to find what you’re looking for in a dark warehouse. I’ve come to believe that learning to understand and trust the knowledge and wisdom of my unconscious is an invaluable tool when it comes to making important decisions based on insufficient information, or in other words, navigating the cluttered hallway of life with imperfect sight.

  3. Maybe, but you would have no way of knowing that it did . . .

  4. I like that metaphor. It is curious to me that we speak of “trusting” our unconscious, or that we can somehow access or communicate with our unconscious. What exactly does that mean? How do our consciousness and our unconscious interact?

  5. This goes back to an earlier conversation between us–sorry to those of you who are joining in the middle.

    Symbol is appropriated from the world wholecloth by our consciousness (consciousness in this sense referring to our unified self). I am not comfortable suggesting that there is no unique frame through which symbols are appropriated. I am comfortable suggesting for debate the notion that we have the capacity–generally realized through the arts: painting, poetry, music, theater, etc…–to consume symbols without digesting them with language. This suggests a modicum of universal human essence. Whoa, yep, just said that. “Human” essence. In spite of our unique self-reflexive frames of reference, there exists a capacity to experience the world on the level of human essence. Or, to put it another way, symbols are a universalizing event whereas language functions in the subjective and the particular.

  6. The arrogance of the consciousness is almost as bad as the fear of it was.

    It’s difficult to have conversations about the (re)preferencing of symbol, or the unconscious, in a world in which the dominant narrative is one of the superiority of the conscious, rational mind.

    I get it. No one wants to go back to the superstitious past. But, that said, I’m beginning to wonder if our patronizing glance at history isn’t a little too anachronistic.

    Harrison deals with this in Forests. Pardon the long quote:

    “Reflecting on the pieties and customs of the past, irony discovers that they were based on errors and arbitrary beliefs. Thus a consciousness that has reached the
    stage of irony tends to repudiate the authority of tradition as lacking in either necessity or justification…. If such irony follows its course toward unrestrained cynicism, it can create the conditions for a new barbarism at the heart of
    enlightened man. Vico calls it ‘the barbarism of reflection.'”

  7. Hmmm. I do not deny the cross-situational power of symbol. However, I wonder what evidence we can offer up for universal symbols. I have read Campbell and those who would point out recurring motifs, both narrative and symbolic, that cut across cultures and ages. But how can we say that each person appropriates a particular symbol in the same way? The swastika is a classic case in point: Does a Shoah survivor appropriate the swastika the same way as a devout Hindu?

    In the end this is a tricky question, and I don’t know that we can come up with a definitive answer. This does not necessarily negate your point: “we have the capacity . . . to consume symbols without digesting them with language.” The question is a) what is the nature of this capacity (that we would be able to identify it), b) do all (or most) humans possess this capacity, and c) is this capacity unique to humans.

    These questions are too broad to tackle here, but I would want to start with a–what exactly do you mean “consume symbols without digesting them with language?” Here, I am not trying to be picky or overly-skeptical. I am only wondering if it is possible that the phenomenon you describe in terms of digesting symbols could be something else entirely.

  8. I’m jumping in only to take a stab at TN’s state, and add some factual information to all of this philosophy.

    Your brain takes your eyeballs’ information and sends it all to different parts of the visual cortex.
    An extremely plausible analogy would be a tub of Lite Brite: Magic Edition pegs being dumped in front of a cluster of lightning-quick children who each do their part in constructing a magical moving portrait of Jackie Chan based on a video that is being told to them in peg-form.

    Different areas of the visual cortex (kids one the Lite Brite translation team) focus on the different aspects of vision (moving-portraiture). The V-Kids’ focuses also overlap, with some subtleties.

    One child (V1) sorts lots of the pegs and passes them out to other kids.
    V1 passes some pegs straight to V2, who hands them to other V-Kids, some of whom are grabbing other pegs from the bucket.
    V1 and V4 both work on orientation and color, but V4 deals with much simpler shapes than V1 (cubes vs. faces). V-Kid 3 probably takes all these different pegs and info about their arrangements from the other kids and puts them on the board for TN’s your viewing pleasure. V-Kid 3 is mysterious though, and experts aren’t really sure what he does yet.

    The point is that different parts of your visual cortex specialize in different tasks. You could incapacitate individual kids and the others would keep working, but pegs would be wasted.

    My *Cough!* Wikipedia-based theory is that TN’s stroke hurt parts of the visual cortex team, but not the parts dealing with orientation. V-Kid 3 could have been taken out of the game, leaving the other kids functioning, but unable to present their amazing Lite Brite movie to TN. TN’s V-Kids 1 and/or 4 are still figuring out where different pegs go on the board without an able V-Kid 3 to put them there.

    TN’s brain could still be learning about the movie without seeing it. Unconscious perception influencing action without conscious comprehension.

    Should I explain our vision in Lite Brite terms for my Senior Project?

  9. Thanks for the great comment Jurian. I am glad that you are bringing us down (up?) to a more concrete level. I like your analogy of the different teams of kids constructing Lite Brite Jackie Chan vid. If you haven’t already you should follow some of the links in the post to read about TN. Some of the reports speculate that other parts of the brain, besides the visual cortex, may be involved in what we term “vision.” So perhaps it would be a similar analogy to the one you offered only different teams of kids would be from different parts of town.

    The Lite Brite idea could be really cool, especially if you could make a video representation of your analogy. GL!

  10. Yes please.