Biology 202 Neurobiology and Behavior Spring 2001

What implications follow from observations made in relation to the blindspot? With regard to vision, to "perception" in general, to the "I-function"?

What implications follow from observations made in relation to the blindspot? With regard to vision, to "perception" in general, to the "I-function"?

To me, more than anything, this blindspot illustrates our ever-present tendency to be wrong, misguided, or one-sided when it comes to perception in general, and our subsequent need as scientists, or just as human beings, to questions our own beliefs. While I am guessing that we do not have tangible holes in our brains that can be likened to the holes in our retinas (although I wonder about some people!), I do think that we all have holes in our cognition, or I-function processes that we like to putty over with rationalizations or made-up stuff to absorb the harsh impact of cars we can't see coming.

Another point I found interesting about the eye discussion was the unconscious interpretation of signs. It was neat to know why people look at the eyes of other people and can tell things about them. This brings to mind scenes from so many movies where the lovers gaze into each other's eyes and see the love between them. I never knew before that it was really a true phenomenon.

The blind spot is probably more of a problem because our eyes don’t really move around that much when we swing our head around to check for cars before changing lanes. It’s so quick; that our eyes only see one frame and the missing chunk of information could be very dangerous. So when I think of the blind spot, I’m really glad that our eyes and brain can work together to make the images of the world around us complete, to the best of our ability.

The idea of blind spot is intriguing in that it does show just how much the brain generates by itself. In reading what Matt brought up about philosophy, I was reminded of something I read in high school, which initially piqued my curiousity for neuroscience. Take the following situation:

A neuroscientist is completely colorblind. She has never physically seen the color red, but she does know how the brain works, how the color receptors in our eyes work, so she knows HOW to see red. The question posed is: is the neuroscientist able to perceive red simply by understanding the method by which it happens? Is she conscious of a color that she's never seen?

Our brains allow us to fill in blanks. Part of perception is the ability to do this, i.e. the blind spot. But is perception really seeing? Like the scenario suggests, understanding does not necessarily allow for experience. Even though we know that we are not truly seeing everything that our perception tells us we are, we don't suddenly stop filling in those holes, which is probably a good thing.It seems to me that perception brings up many questions about what the brain is really doing, questions that move away from biology and behavior into more speculative realms.

On the flip side, I have not historically trusted that which (apparently) is there and is seen by some part of my NS, but which "I" don't see. Call it intuition or "getting a feeling" - I've never quite believed it, although now I'm told it's based on real information. The example of staring into a lover's (or a potential lover's) eyes is a good one; certainly, I've gotten a feel for someone's interest before based on certain visual cues, but since I wasn't aware of it, I often dismissed it. It was almost certainly real, but I didn't trust it, whereas the vision in my blind spot is not real, but I do trust it.

This all seems somewhat contradictory, but of course, it's not really; it just reinforces the strength of the I-function. "I" believe what "I" am aware of. Actually, now that I think of it, this may not be true for others. Certainly, a lot of people believe pretty strongly in things they can't "be aware of," and a lot of behavior in many people is determined by intuition. This sort of goes to the question raised on Tuesday about the purpose of the I-function: if many behaviors are better performed without the involvement of the I-function, why do we need it at all? To extend this question, sometimes it seems that I would actually be better off without an I-function. It certainly inhibits a lot of potentially beneficial behavior -- acting on a relationship intuition, say, or even volunteering an extemporaneous comment in class.

My point is not to turn this into my own little therapy session though; my point is that this inhibition of behavior is a likely candidate to explain the existence of the I-function. When we think about things, that is, when we involve the I-function, we come to understand how actions will affect our livelihood. Making it personal in this way can lead to pretty strong emotions that would not be there if we were to act automatically. These emotions that are generated by the involvement of the I-function are often what inhibits certain behaviors, and from an evolutionary standpoint, it's probably better to do too little than to do too much, in much the same way as the nervous system's homeostatic mechanism works to keep things the same. That's all pretty much based on hypothesis and personal experience, though.

A thought came to mind after Tuesday's class. When we talked about telepathy and twins, I remembered watching the Oprah Winfrey Show years ago about a set of twins. One of the twins experienced pregnancy pains of the other twin (who was giving birth). In this situation, could it be that their I-functions or their cells had split genetically during mitosis? It's all so fascinating to me.

Although, in some ways this notion really calls the nature of the I-function into question. If the I-function is altering reality, but the I-function is based on observations of reality..what is altering what? It just seems very circular. The only way I really conceive of the I-function is as my thinking self. The part I know about, but my I-function fills in the detail of my blindspot without me knowing about it. If that is true, then what am I?

Besides what this could tell us about the brain, this research is being used as a means to help deaf children learn to speak. The children watch Baldy moving his mouth on a computer and then imitate his lip and tongue movements to produce sounds. There is lots more information on the following website: http://mambo.ucsc.edu/psl/pslfan.html . You can also access a clip of Diane Sawyer as animated by the scientists for PrimeTime, which is especially amusing.

So, I think I just wanted to put this out there-- that some of what we are talking about as "made up by the brain" may be a result of other impulses from other senses. I am not arguing that this is always the case-- what other senses could be involved in looking at a black line? Still, it makes me feel a little better to know that how we percieve the world cannot be a complete hoax.

Also, what about the...something... (Not eye function, but not direct stimulation) that somehow, in our head, matches up the 2 views of our eyes? The thing that we see in our brain is Neither of the images on either of our eyes, but a Perfectly overlapping mix of the two. That's pretty incredible, how does that happen?

In looking over the comments, I was also interested by Alice's input. Based on the research that she discussed, I am convinced that at least some aspects of the making up of reality can be attributed to clues from other senses, but it can't be possible that they all are. After all, with the examples on Serendip and even our blindspot problem, the only cues are visual; there are no tactile or audio perceptions to be had. In support of the research with Baldy, though, I have been thinking about the role of synesthesia as an associated process. Could synesthesia be the result of similar processes in which cues from one or another sense are used to creat a signal to another sense?

In terms of the I-function, these thoughts are really significant. As others have mentioned, so much of our perception of reality and, in effect, our behaviors (even ones we are aware of) are the result of a fabricated universe. The thing to remember, however, is that the I-function can override instincts in many, albeit not all, cases, and that without the I-function, we wouldn't even be having this discussion. In pondering the look in lovers' eyes, etc. etc., it would seem to me that without the I-function, the feeling of love (specifically love, not just lust) may not even be possible. Depending on your concept of love, I can see this as being debatable, but the physical cues which signify a meaningful relationship are still there (of course, I am assuming that there are cues which signal as much).

Just as a thought in conjunction with Niru's comments---so does this mean that some people are genetically pre-disposed to, say, fall in love less or so their attraction to others less? For example, there is the gender issue...I've definitely read plenty of magazine which would indicate that the body languages of men and women differ significantly, but they weren't exactly scientific journals, so it's still questionable to me. If your genetic makeup supports falsifying cues less, can that make you a better driver or better at catching spelling errors?

I have some other questions, but I want to wait and see what this Tuesday's discussion has to say about some of the ones already mentioned before I go on.

As for the blind spot, we are not aware of it because it is always there. It is just like the fact that you are not aware that you blink your eyes quite often unless you think about it or do something to be conscious of it. We are not aware of the blind spot because our eyes are moving and scanning the room so anything that is in the blind spot is not in the next moment. Thus, except for small details, our brain can use the memory of previous information to make up for information that is missing. I find it pretty amazing that something so small is so powerful.

I am interested in learning what else the brain "makes up"? How often does this phenomenon occur? I do not think we will ever know the answer because we do not know how much the brain is filling in for us in each thing our perception is telling us we are seeing.

In the examples in class, everyone's I-function was creating the same dot that did not actually appear on the paper. When will one person's I-function make up one thing and my I-function create something else? This must occur as we all can percieve different things when examining the same picture. (like the old lady/young girl figure) I believe that the I-function accounts for each person's uniqueness as it can arbitrarily choose what it wants us to see and not see.

While we were talking about the brain "making up" visual information, I began to think about hallucinations. What exactly is a hallucination in terms of the nervous system? Clearly, there is no sensory input coming into the eye causing such a vision. So where does it come from? And how does it manifest itself on the retina? Is the brain making up information as it does with the blind spot?

Another question I have is how is a "visual image" stored in the brain as a memory? And how can we "see" something while we are asleep and our eyes are closed?

So my question is, because I knew the dots weren't really there but saw them anyway, was I really seeing them or was it a trick of my brain? I mean, I know that each eye sees a seperate field of vision and then our brains put them together so they match. So is this overlapping picture really what we see, or just what we think we see (because in this example the pictures overlapped to form a false immage)? I don't think this is very clear, but I don't know if I can make it more so. Maybe I'm asking for the definition of the word "see" for this class. Is what we see just the light reflections picked up by our eyes, or does that have to be processed, sent, recieved, and interpreted before we are calling it seing?

I had actually heard of studies where it was thought that imagination enhances our ability to see what's really there. The example they used was that it was easier to identify a friend in a crowd when he actually appears. From this it makes sense that blind-spots are perhaps pre-stored patterns or “images.”

This idea of a blindspot had me thinking about horses. I have watched programs on how the eye of the horse works and it seems that the blindspot that they have to deal with much more difficult. The fact that they can't see something when it is right in front of them (like a jump). When you approach a jump the horse can see an image of the jump in each eye and then as you get closer the images start to come together, but then about 1 stride away from the jump, the horse can no longer see it and relies on memory and the rider, to determine when to jump and how high to pick up his feet. Everytime I think about it it makes me think even how more amazing animals are.

Of course their eyes evolved differently than our own because of their need to be able to see around them for predators. This way with just a slight turn of the head they can see behind themselves, very important for survival.

This blind spot "fill in" brings the human machine to a level of what it is--fascinatingly complex but not complete; just doing what it can to survive.

What could be in our environment that we have not developed bioelectrical skills to perceive. Our eyesight only catches a certain speed of image. What might be flashing in our world at a faster rate than we can see and does this have any subliminal effect on us?

| Course Home Page | Forum | Brain and Behavior | Serendip Home |