Week 8 - Neurobiology and Behavior

Although somewhat old hat by now, I find Malcolm Gladwell's book "Blink" to be particularly relevant to our discussion concerning vision. The premise of his argument is centered around the idea of an intuitive reaction to a certain (visual) stimulus. He makes three solid examples: a curator or art historian views a statue and immediately recognizes the piece as a fake; a tennis coach witnesses a player toss up a ball and from this directly knows that the ball will hit the net; and finally the most astonishing, a behavorial expert is privy to a couple's brief interaction and from this encounter can determine if the couple will divorce eventually.

Gladwell contends, "The power of knowing, in the first two seconds, is not a gift magically given to a fortunate few. It is an ability we can all build for ourselves."

Evidently, the link between one's vision, mind, and resulting "judgment" (if one can even call it that; perhaps more accurately termed "reflex") is incredibly strong. This raises several interesting questions, namely, if one makes decisions and judgment calls without any real reflection, how does free thought and free will function in our consciousness? Can we do anything to exert more control over our mind's processes? Are we really in the so-called driver's seat? Or are we merely passengers?

At the end of our last class our understanding of reality was questioned because of the existence of our blind spot. This led me to wonder what happens when someone chooses to actually use a hallucinogen and chemically distort their ability to understand and interact with reality. Some effects seem to be an inability to understand the passage of time or to understand that objects and people around you are real. In general it seems to cause your brain to interpret visual images and the world around you differently.

            Some explanations for the effect of hallucinogens on the brain are that hallucinogens have similar structures to serotonin. They disrupt the interaction of nerve cells and the neurotransmitter serotonin. Serotonin is distributed throughout the brain and is involved in the control of many systems including behavioral, perceptual, and regulatory systems. Understanding that the distortion of the serotonin system will have huge effects on the brain, I still do not entirely understand how ones ability to see things normally is distorted. What are the exact neurological effects of serotonin on the “perceptual” system and how do hallucinogens change what is going on? Does something happen to the images that you see- once the images reach your brain is your brain unable to process them as it normally would? If that is what is happening could it also be interpreted that vision has an effect on how we interpret time, since ones sense of time is also distorted when “tripping”?

http://www.nida.nih.gov/Infofacts/LSD.html

As demonstrated in class last Thursday, there is a blind spot in our retina. We found it by using the cross and the dot on a sheet of paper. But when we could no longer see the dot we did not see a hole or blank spot, instead we saw white. Immediately I thought about whether or not this qualified as a hallucination. I know I saw something that wasn't there. This must mean I am always seeing something that isn't there. Standing outside a building I might see a wall where there is really a window only because the window is in my blind spot and is surrounded by the brick wall, which I can see. As far as I know I have never hallucinated to any extent larger than my blind spot(s). But if the human brain is capable of generating and perceiving mental images without receiving input then I have to start questioning reality in terms of what I am seeing. Can I really trust my brain to give me an accurate image of what is in front of me?

Although many have already registered their fascination with the last lecture already, I'd might as well throw my hat into the ring. Last class was particularly interesting because we melded mechanics with philosophy. I enjoy philosophical, abstract conversations as much as the next person but it is nice to have something more solid to grapple with. We've been learning about the biology behind nervous systems and applying that to philosophical issues quite a bit in this course; however, it's easy to lose sight of the actual biological mechanisms underlying the problems we've been discussing. This topic of visual perception and eye anatomy is so fascinating because it lets us see the man behind the curtain. We now know in what ways the very structure of our eyes limits us in perceiving reality.

The idea that we can perceive things by way of registering points of reflected light is a simple one, yet it's an idea I've always had trouble articulating. I would think about it a lot as a child when I was trying to figure out just what reality was. I couldn't figure out what it was that I was perceiving. Without anyone telling me, I intuitively felt that the world I saw around me might not be the world as it truly is, that my vision was dictated by the physical structures that enabled me to see (talk about catch-22). This issue seems especially pertinent when dealing with art. Who else has been frustrated when trying to draw from a certain perspective or trying to shade just so? The same thing goes for 3D computer modeling. How do we represent reality realistically? What cues us that one object is facing away a few degrees as opposed to straight on? How can we really tell the difference between an object and the background? It's not as if we're cartoon characters with thick, black outlines after all. It's hard to convey even these ideas, since they're taken for granted in day to day life. But if we consciously think about it, it becomes clear that a lot is going on here.

In any case, it's comforting (although I guess for others it's disconcerting) to know that certain quirks in the human visual system can be explained by basic physical principles.

How does one explain intuitions? Why is it sometimes when an incident occurs a person will say, " i knew that was coming" or " i had an inkling something like that was goign to happen" Is this intuition a legit process of the brain's sensory system or is it just a phenomenon that we can't explain? The book Blink delves into " thin-slicing", and it got me to think that maybe all this intuition feelings are just daily thin slicing that people have accustomed themselves to but are just unaware. How much of what we sense is actually psychological or really a sixth sense?

Before we returned from spring break and began looking at the sensory side of the nervous system and vision, I read a very interesting article called “Illusory Color & the Brain.” The article talk about how the role of color for most people seems to be to illustrate what we see in everyday life. However, color is merely a perception in the brain. In fact, when it comes down to it, while color does help us differentiate between objects, the part of the brain that deals movement and navigation is essentially color-blind. With this in mind, it seems that color has much less role in defining form and depth that one might have thought. But then there is the study of illusory colors – colors that the brain is “tricked” into seeing, much like we discussed in class. As has been mentioned, the basics of visual perception are that photons are absorbed by rods/cons in the retina, transmitting a signal through neurons to ganglion cells in the retina. Contrast – and thus the detection of edges - in our vision is created when ganglion cells fire maximally when their center is lighter (for an on ganglion) or darker (for an off ganglion) than its surroundings. This part of perception has little to do with color. However, in visual experiments researchers found that the visual cortex in the brain might respond to the direction of borders when color is involved. I couldn’t find a good image of it, but the example they used were two thin, jaggedy, red lines roughly shaped like the Italian peninsula. In on of them there was second, orange border on the inside of the shape, and on one an orange border on the outside. In the shape with the orange in the inside, the shape seemed to be a little elevated off the page and the color seems to spread throughout the empty space in the middle. The shape with the orange on the outside made the shape seem repressed into the page. Researches think that a possible explanation for this is that neurons respond to a certain type of contour when there is a lighter color against a darker color, or visa versa. They give a lot more examples of these visual illusion tricks, but seeing as that last one was hard to describe and probably made no sense you can find the article in the March 2007 issue of Scientific American. Basically, there is a separation in the brain between color and basic visual perception, but in both cases the brain can create illusions of things that aren’t really there, sometimes even combining the two.

http://www.scientificamericandigital.com/index.cfm?fa=Products.ViewIssuePreview&ARTICLEID_CHAR=A2A84A32-2B35-221B-64B064E7B4B41259

It was "revealed" to us last class that the picture in our heads is larger than the picture on our retinas... Shouldn't we have already known that? Our eyes are so small, and our brains are supposedly "wider than the sky," so it shouldn't be difficult for us to comprehend that the retina picture is smaller. However, it's uncomfortable to know that picture transmission from retina to brain is done completely without the I-function. Other students have brought up the issue of reality on this blog. If our percieved vision is transposed without our knowledge, then our perception of reality could be skewed without our realization. Perhaps we are seeing the world through rose-colored lenses...or something of the sort. The scientific explanation is that our eyes are always moving, and the brain pieces together the small images from the retina. While I'm walking around, however, I don't feel my eyes rapidly scanning, or my brain piecing together myriad images. This is done so quickly, and without consciousness. That's incredible. On the contrary, it's frightening to continually realize the actions that are perfomed without conscious effort. I don't necessarily believe that what we are seeing isn't reality. To us, at least, it is reality....and that's really all that we need to know. However, I do think it's interesting that we could all be percieving the world differently. If one person's eyes don't move as rapidy as another persons, is their vision imperfect? Is it perhaps less sharp, less detailed, missing pieces, etc...? How fascinating the topic of vision is....

I was just looking through the news aggregator and I came across a rather interesting title of an article so I thought I would read further, and I was very intrigued by this subject. The article is titled "Brain Injury Said to Affect Moral Choices" located in the science section of the New York Times.

The area of the brain associated with this described damage is the ventromedial prefrontal cortex and is located behind the forehead, more specifically a few inches behind the eyes. The prefrontal cortex is general involved with short-term memory and damage to this prefrontal cortex can cause short-term memory deficits. Furthermore, it has been said to be associated with higher cognitive functions such as language, abstract reasoning, problem solving, social interactions, and planning. Therefore, when I read: "Damage to an area of the brain transforms the way people make moral judgments in life-or-death situations. In a new study, people with this rare injury expressed increased willingness to kill or harm another person if doing so would save others’ lives" I tied it back to the cognitive functions listed above and it seemed to make complete sense. If there is damage to the prefrontal cortex, then the individual might experience difficulties and deficits when it comes to abstract reasoning, problem solving, social interactions, etc, all of which can be involved with making moral decisions. However, it does seem a bit extremem to just let an infant suffocate and endorse death/killings in high conflict situations. It's interesting how individuals with this damage to their brain resort to violent efforts in crisis situations. I started to wonder about the environmental role in these situations. Does the individual's instruction throughout his or her childhood and further development based on the environment in which he or she was raised have any affect on the moral choice these brain damaged individual's seem to make? Do those prior teachings just become erased from the brain? Are they considered short term memories since the prefrontal cortex is associated with short term memory?

Additionally, I began to think about the military a bit, especially when I read one quote from a patient of the doctor that stated: "Jeez, I’ve turned into a killer." I began to wonder if there is any connection between the individuals in the military who are instructed to kill and preform often ruthless tactics to kill people at times and the brain damage to the ventromedial prefrontal cortex. It might be interesting to extend this study into the military forces to investigate if maybe there is a certain type of person, a certain type of brain that is geared for the military.

Also, it seems as if these brain damaged individuals sacrifice lived without question at time, but what happens when their own lives are at stake? Does the damage to the ventromedial prefrontal cortex change any moral judgement in relation to that individual or is it applied to more external forces, people other than that individual. It would be interesting to really examine the emotions involved here since the prefrontal cortex is said to be involved with giving rise to social emotions. However, what are truly social emotions and how are they all subdivided? Are some emotions hindered while others are enhanced? What is the connection between all of these? It's just really interesting that judgement can be controlled and altered by brain damage regardless of how the individual was brought up.

If anyone wants to read this article, the link is right below:

http://www.nytimes.com/2007/03/22/science/22brain.html?ex=1332216000&en=f5bb061d194af5fa&ei=5088&partner=rssnyt&emc=rss

It all started in with the eyes. Our discussion this week about vision as a model for how the sensory side of the nervous system works has proved to be nothing less than troublesome. So a recap: we have this fabulous little sensory organ called the eye. Two eyes work together in a pair, responding to changes in light which cause permeability changes thus causing action potentials. The eyes are able to conceal each one’s discrepancies (i.e. the “blind spot”) and depend on the brain for interpretation of what is perceived. The “facts” about what is “actually happening” is fine…well, sort of. Okay, none of this is really fine for me, and let me explain why:

We see the world as it is, right? More appropriately, the world appears to us the way we see it. There are some fundamental difficulties (for me) about the way we “see” reality. The way we see reality is subject to a large amount of mutation. We receive an input through changes in light and these changes are compiled as many point sources of light, but this light can be misleading. Everything needs to operate correctly, or else the point sources of light aren’t added up correctly on the retina and the image may not appear to be what it actually is. Another complication is that the image that is projected on your retina is upside down and backward – the brain has to do a lot of twisting and turning to make things appear to you as they actually are. And then there is the fact the image is a lot bigger than what gets onto your retina, so the image has to shrink and then be put back together; this leads into the fact that your eyes are always moving and re-evaluating and adding up pictures and changing their interpretation of reality. The reality you get, or the picture that finally is your experience, has been accomplished through a significant amount of mutation, changes and guessing. With this system how are we to even feel confident that we are accessing the “right” reality since the system of our eyes seem to operate on the principal that the reality we see is constantly being altered and changed depending on your position, etc.? Thus, if there are problems about the way we see reality, and seeing is a model for how the sensory side of the nervous system works, then for me, there are difficulties with this system.

We know there are very few sensory neurons relative to the number of neurons in the body. Why is this true? Is there are reason that we don’t have a richer amount of input? (This question is operating under the assumption that more neurons equal a richer experience, which seems logical—although possibly incorrect—conclusion) Has the sensory experience of humans altered over time? What would your experience of reality be like if you had a larger proportion of sensory neurons? I think the reality that we experience is something that we agree on and this consensus is innate in what it means to be a part of Homo sapiens. I think then it is essential to recognize how our reality is shaped by our sensory system.

If the human design is a conserved process then it seems that our sensory experience also follows from a conserved process. The reality which we see and the reality which we participate in may be the same, but they also may be limited. It seems to me that we are participating in a convergent type of reality—we have similar sensory experiences and because of our conserved design and development we have a certain type of experience. In my opinion, if we were able to amplify our sensory experience, we may be able to access a very different type of reality. I think it is safe to say that our “reality” may not be the only thing out there, but it is the only thing that we have access to. Kant also said this, but I want to go beyond and say that the reality we experienced is because of a convergence theory of what is appropriate for our sensory systems. Maybe the reality we experience is a product of what we can handle; or what our brains can interpret; or what our nervous system can respond to. It may in fact be the sensory system that has dictated our experiences within reality.

I went back to my psychology book from the course Behavioral Neuroscience, "Physiology of Behavoir" by Carlson, and looked at the chapter on vision.  At the start of each chapter there is a description of a particualr case study.  For this chapter, Mrs. R was the patient.  She had suffered a stroke that affected her vision.  She could not identify objects, but could describe the object by it parts.  (A wristwatch was put in front of her, she knew it was a circle with two things attached at the top and bottom, but couldn't come up with the word, 'watch.')  As soon as she picks up an object and feels it, she can identify it.  She can only identify people by the sounds of their voice and the way they walk, not their faces.The sensory receptors in Mrs. R's ears (hearing) and hands (touch) obviously still are completely in tact, but one step of communication between her eyes and her brain is broken.  There must be multiple levels of processing to interpret the picture on the retina of the eye.  Looking at the case of Mrs. R. there must be at least one level to identify the parts of an object, and another to put a name and function to the object.  There is probably another whole section that processes movement and putting names and functions to those movements (this pathway seems to be unaffected in Mrs. R.)Recognizing what you see is not a simple process; there are different levels of processing and different pathways.  It will be interesting to see in the upcoming lectures to see how our brains can make a comprehensible picture entirely different from the image on the retina.  The brain must play tricks on us.  The picture in our head is really only nominally related to the picture in on our eyes. Going a step further, the picture I have in my brain, and the picture in yours must be really different purely based on the fact that the initial image must go through many steps in processing.  And when there are a lot of steps, there's a lot of room for differences from person to person.What do you see?

I always thought my unique word associations were testament to my being an English Major and a writer. I had only ever heard of the word "synesthesia" in an English course talking about cross-sensory metaphors. The root of the word is Greek meaning roughly “union of sensation” and until last week’s Neurobiology and Behavior course, I had never in my life considered my personal habits to be a neurological symptom of a condition. After further reading I discovered that most synesthetics are never formally diagnosed because their thinking isn’t wrong or weird to them and thus no cause for alarm. There is a distinction to be drawn between genetic synesthetics and event related causes. For example, if I had dropped a lot of acid in the 60’s, there would be good reason for me to associate colors with numbers and tastes with words. Stroke survivors and others involved in traumatic events often report synesthetic responses.

I am intrigued by the behavioral differences between synesthetics and non-synesthetics in life and in the rest of the nervous system. How is someone who associates – no joke – the word “choose” with the taste and smell of french toast wired differently than the person next to her in class? Has it made a major difference in my life? Is that why I am inherently creative because I cannot conceive of thinking differently? This condition is fascinating and I wonder just how prevalent it is.

Yesterday, I had to spend all day driving to Connecticut to pick up my car and while driving back I was contemplating vision and what I was seeing and what my brain was “filling in.”  It amazed me to think that the other cars, the road, my steering wheel, everything was a just points of light, two dimension images on my retina that appeared to me as three dimensional images.  Now I am wondering where my blind spots are and as I maneuver around my world try to image all of the possibilities that are available with this.  I know that we are only studying the vision sensory system but this has made me realize that all sensory systems must be working together.  Obviously corollary discharge and photoreceptors are coming into play just I never realized the extent to which they are.  If our brain is effectively filling in blank spots it must communicate with our sense of touch so that if we feel something our brain must signal to us that we see it.  The same must be true with hearing and smell.  If we see a door slam out of the corner of our eye that we must hear the sound too.  Perhaps illusions (like magical illusions) or hallucinations are signals that our brain is sending to our eyes “we see this image” but our sense of touch is not keeping up that’s why we can pass our hand through the image and not feel anything.  I am beginning to think that perhaps many forms of psychosis can be explained this way.  If the corollary discharge in a individuals is not regulated properly they may hear and see things that are not there such as in schizophrenia, is their brain effectively making up bad “fill-ins?”  Just curious if anyone can think of any other disorders that may be the result of this sensory system make up.

In class we discussed how we don’t really see what is actually there. We have areas in the eye that do not have photoreceptors and the areas that do have photoreceptors are organized in a way that makes no sense. If these photoreceptors enable us to see what they have the ability to see (2-d) how do we know something is 3-dimensional? I can’t understand how we think we are seeing reality but we are actually just seeing 2 dimensional images with blind spots that lie make us think we are seeing reality? But my question is, What is reality? And, why do we want to see it?

If we see what our eyes have been engineered to see and we think it is reality, then is it like the movie, “The Matrix” where we think we are living in reality but we are actually not? If our eyes have holes that our brain fills, do our brains also have holes that our neurons fill in? If we have a blind spot in one of our organs then why would it seem so outrageous that we have some kind of “blind spot” in other organs or maybe even all our organs?

What is reality? Who decides what reality is? If we are all individuals and we have our own perspectives then don’t we all just have our own version of reality? How can someone dictate what reality is or isn’t if they are experiencing their own version of it? Is this website real or is it something our brain imagines is there because we think we see it, but what we are seeing is a screen that tells us we are looking at a website? This topic makes me question everything because it’s a topic of reality. How can I think of reality if I don’t know what reality is? How do we define this term, “reality”? Is it just seven letters that has been programmed into our brains to believe what we are seeing is really what this term means?

I feel as though I am going around in circles and cannot stop questioning what reality is. I want to know what I am seeing is the truth and it is the reality but now I am not sure it is? I seem to look at objects thinking, well if I move my head this way am I seeing everything or am I still seeing some type of a “blindspot”? Do we have “blindspots” everywhere? How do we know? How can we be sure?

On a different side of the same topic, I want to pose another question, How does 3D animation work? We usually see the characters but can see through them, so how do we trick our mind into believing that something is going into the audience if we can somewhat see through the image and know that it is not really there? Is it our eyes that are doing the thinking even though we know it is fake? How do we see and believe that this three dimensional image is really there? If we are looking at the light coming off an object and our brain is analyzing the different types of light coming off different objects to create this image what is 3D and how does it trick our minds?

Like most everyone else in class I was fascinated by the idea of our brain filling in the gaps that the information on the retina cannot supply with something created exclusively by the brain. I’ve read about experiments where people were shown a room and told that it was an office. Afterwards, during a recall session, most of them reported seeing books in it…even though there actually were no books present.  The brain’s ability to create something out of nothing…to process patterns and fill in gaps…this is a truly amazing thing. This phenomenon seems to be completely independent of the I-function. Even when I consciously realize that in a second that dot will disappear and that there ought to be nothing there, a black hole…still I continue to see the paper that doesn’t actually exist. Where then is my I-function? I am not consciously creating that paper…or the extra red dot instead of a yellow one. It follows then that the process is a function of the brain not related in anyway to the I-function. We’ve talked so much about it and now it seems that after all the nervous system really does not have a conductor. It seems that the I-function either has no control over our perception and the various parts of the brain that create the patterns we think we see, or, which is still more disturbing, that it perhaps doesn’t exist at all.   

On another note, it occurred to me that if it’s perfectly normal for the brain to create what it thinks it ought to be seeing then where do we draw the line between sanity and insanity? Why is it normal to see a dot where no dot actually exists and not normal to have hallucinations or visions. Are hallucinations just the products of the brain filling in the gaps? You see an eerie light and you hear an odd noise and your brain leaps to the conclusion that you have witnessed the arrival of an extra terrestrial being.

Over break I had the pleasure of stumbling across a FASCINATING article in March 11th, 2007 issue of The New York Times Magazine. My father had left the magazine, whose cover read “Neurolaw” in bold letters, on the kitchen counter (this article was also referenced by Professor Grobstein in last week's forum). As I looked closer, I was able to see that the entire title read “The Trials of Neurolaw: How Advances in Brain Science Could Transform Our Legal System.” The article was packed with information, and will be the topic of my next web paper.

Although I could write an extensive paper on the article, I will attempt to discuss it in short. The article spoke about the use of neuroscience in the court of law. Due to somewhat new technology, brain scans are now being utilized in criminal trials. Although this is interesting in all cases, it is especially interesting in capital cases, when many philosophical questions arise. Does it matter whether a man killed his wife because mother because he had an abnormal cyst pressing on his arachnoid membrane? Are abnormal brain scans equivalent to acting under duress or suffering from a serious rationality defect in the court of law? Combining these questions with the fact that many scientists are still uncomfortable with how new and untested the brain scan technology is, utilizing it in the court of law is a debated discussion.

Will we force witnesses and suspects to get brain scans? Will jury consultants use brain scans in jury selection? In the future, will we use brain scans to predict actions and crimes?

This article began to scare me as it reminded me of a recent movie called Minority Report. The films tagline was “What would you do if you were accused of a murder, you had not committed…yet?” and followed the adventure of a detective who was accused of thinking about committing a crime he was not planning on committing. Science, similarly to everything else in life, cannot be perfect 100% of time. However, I was comforted to know that a coalition of social scientists, psychologists, lawyers, and biologists have all joined forces to fight for the ethical use of brain scans.

Again, I apologize for the brevity of this post. My webpaper promises to go into more detail.

Have any of you ever been asked this question:

Wht mks t s tht y cn stll rd ths sntnc vn thgh thr r n vwls n t? 

I, for one, had always read things like this and thought about how silly they were (and promptly deleted them). However, it was in Thursday’s class that I actually realized how incredibly smart this is and what it implies about the dynamics of our vision. Essentially, what you do is remove all of the vowels from a sentence or a paragraph. The amazing thing is that you are still perfectly capable of understanding what you have read despite the fact that you are only reading a bunch of consonants. The sentence above (in case you didn’t get it) is ‘what makes it so that you can read this sentence even though there are no vowels in it?’ This is a very good question, and I feel as though Thursday’s discussion allowed me to better comprehend this phenomenon.  

 By looking at the nature of the retina and the difference between the image on the retina and the image in our head, we were able to infer that our brain fills in what it believes there should be. In the same way, therefore, that the brain fills in the holes (from where there are no photoreceptors in the retina) in the picture in your head, can your brain fill in the ‘holes’ left by the vowels in words? What we can take from this example is that words are not read letter by letter; rather we recognize words as wholes, and the absence of vowels does not reduce the understanding of our text. Another interesting question that this brings up is what role the I-function plays in reading. It would seem that by automatically filling in vowels when you are reading a sentence like the one above, you are essentially interpreting things which have nothing to do with the information that is coming from your eye. In the same way that unbeknownst to you, your brain is adding visual images that are absent on the retina, is there a part of your brain or nervous system which is creating the experience of reading whole words even though that experience is non-existent?

In class we learned that pain is not a sensory modality and yet I feel as if I am able to sense pain. If I scratch my arm, I feel the pressure of my finger, but also a sense of pain. Oftentimes if a person gets a cut, he doesn’t realize that it hurts until he sees the cut. The pain appears to be initiated by his visual confirmation. However, if I scratch my arm while closing my eyes, I still feel both pressure and pain. There is more to it then the visual reafferent loop. If pain is merely a device of the nervous system, then is it a learned device or do we innately possess the ability to feel pain?

What exactly is pain? Biologically the pain we experience is separate from nociception, which is the measurable and physiological component to events that usually involve pain. However, pain can occur without nociception and visa versa. Nociception involves the transferring of information, such as inflammation or damage, to the brain and spinal chord. (wikipedia: pain and nociception) Pain doesn’t seem to hold any physiological component. Does this mean it is purely psychological?