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Neurobiology and Behavior, Week 4
Welcome to the on-line forum associated with the Biology 202 at Bryn Mawr College. Its a way to keep conversations going between course meetings, and to do so in a way that makes our conversations available to other who may in turn have interesting thoughts to contribute to them. Leave whatever thoughts in progress you think might be useful to others, see what other people are thinking, and add thoughts that that in turn generates in you.
As always, you're free to write about whatever thoughts you add this week. But if you need something to get you started, what do you think of the idea that actions, perceptions, and thoughts are patterns of activity across populations of neurons? that there is a distinct "I-function" box that is responsible for internal experiences, including pain and the initiation of willful action?
When I dance I do not
A Reconceptualization of the I-Function
A few years ago I suffered an injury which caused me to lose all sensation in my leg due to over nerve damage. The doctors would come into my hospital room periodically and command me to wiggle my toes, which no matter how hard I concentrated, I was never able to do. The I-Function to me seems to be not only your willpower but your power (ability) to effectively carry out actins that you mentally intend to do. It was not enough for my brain to send the signals to my toes, but necessary for my toes to consequently move as a result of the signal, right? But can the I-Function alternately be define by what one cannot so or experience? I know this sounds counter-intuitive (to define something by what it is not) but I am just curious-can one argue that the I-Function can be defined just as much by what it can do as what it cannot do; i.e. can I say that my inability to wiggle my toes or to experience sensation in my feet are also a function of my I-Function?
What is Thinking?
I, like Max, and am also intrigued by the evolution of the nervous system. On a cellular and microorganismal level, as Max alludes to with viruses and microbes, it is indeed true that there is an order and pattern by which these organisms behave. One might argue that viruses and microbes 'think.'
I think neuroscientists (e.g. Dr. Grobstein) might take issue with such a statement though, because it seems that an understanding of the brain presumes that differentiating between life that 'thinks' and life that does not is the difference between cognitive (i.e. processing of data) abilities.
As one who spent this summer studying microbes and their absurd ways of making a living, I do agree that their activity with their neighbors as well as with their environment does neccessitate a better definition of what defines life and, more specifically, thought.
I-function & Individuality
evolution of the nervous system
I realize that this doesn't provide immediate insight into "boxes within boxes" or the "I-function," but I've been wondering lately about the evolution of the nervous system. Perhaps we can't track exactly when or how the first "nervous system" arose, but doesn't anyone else wonder why?
I was thinking about single cells, replete structures that can survive and interact with their environment alone. Clearly they do receive and process data. It may not be considered "consciousness," but receptor proteins along the cell membrane are always relaying outside information, even if this is only a rise in hormones. Is this not analagous to a "nervous system?"
Is it simply that when single cells started bundling together for increased surival rates and mutual protection, there had to evolve specialized cells - neurons - to serve as more a sophisticated means of regulating environmental/inner data with the more complicated structure?
Perhaps I'm just devolving into petty mysticism, but where does one begin to sanctify life as complex and conscious? Cells (eukaryotes at least) have their own attendent organs (organelles, yes?) and are the foundation from which all large, "complex" organisms arise. But cells do behave, yes? They work together to form societal like structures and some will sacrifice themselves for the common good. Cancer is a cell gone haywire, a cell that no longer recognizes its surroundings due to faulty receptors and behaves inappropriately, reproducing itself and the corrupted genetic material it houses.
What about viruses? Is anything without a true "nervous system" simply diffusing and operating under "random" gradients and pressures? Is "behavior" only a meaningful distinction when applied to large organisms with systems of interconnected neuron cells?
The physical and the elusive
The I function bothers me. Actually, the I function, and what it is itself doesnt bother me, but it being a box in our other boxes bothers me. The way I see it, the other boxes we have spoken of so far are actual physical entities. Nuerons, Amygdala, Neocortex, they're phsyical representations of the nervous system, one fitting into the other or combining into another. The action and resting potentials too are actual phsyical (and chemical) changes taking place with the movement of ions in nuerons.
But the I function can't be pinned down. It's elusive. It's essentially who we are. At this point I realise that so far, we have agreed that all that we are is a function of the way the brain acts, and this then gives that the I function is a function of the brain. But, is it, really? What of people in a persistent vegetative state? They have lost large amounts of the I-function, but the brain is not dead.
And for something as abstract and complicated as the I-function (a person's character, individuality, decision making), can just physical interactions between nuerons be held accountable? I find it hard to get my head around this divide.
It has been established
It has been established that the I-function allows one to act willfully and to carry out an intention. In the case of Christopher Reeves, it is interesting to think that he lost this function of being able to will anything to happen to him below his head. However, in some sense he did not lose the I function because he is aware of his surroundings, and still retains the ability to say I. With the I function is there a line drawn between the physicial and "other" connection? What accounts for the ability for Christoper Reeves to still retain self awareness? I agree with others that the case of Christopher Reeves supports Descartes model. There has to be something else that accounts for the ability to say I, even if one cannot experience it.
To think in terms of pain is also interesting. If pain is a pattern of activity in the I function, how come one cannot control the intensity of pain, or if they can control the intensity of pain, it is exceedingly difficult. Is pain housed in a separate compartment of the I function that is less accessible? In this way it would seem that pain is just a state of mind, but I would hardly agree with that.
mirror, mirror
Another topic that is important to address is the concept of emotions. I don’t know much about research being done in this area, but from a behavioral point of view it seems that actions are not caused by emotions, but rather that emotions influence actions. In other words, there’s no one way to act happy or sad or angry or scared. Rather, simultaneous actions occur while a person is in a particular emotional state. Perhaps a new summary of observations could be that emotional boxes are interconnected with boxes that mediate action and that these connections strengthen or die out over time as we assess how successfully our actions manipulated the environment.
Willful Action
Although we were first exposed to our new vocabulary, “I-function,” I think we have earlier thought about it or even have known of this before. Integrating what we know with our observations made in class is not so easy. Since we have agreed on our newly made observation in which our brain is different because our neurons are arranged in different ways, I think I can integrate it with the “I-function” being different among others based on different pattern of neurons, individual’s different value/belief carved in one’s neuron, and different degree/pattern of self-actualization.
I think “I-function” is similar to self-actualization in psychology. Self-actualization implies the attainment of the basic needs of physiological, security, love/belongingness, and self-esteem. Human by nature has a desire to fulfill these elements. For example, if someone likes music, s/he would have more I-function to initiate playing the piano.
Also, we have social expectation that we need to follow. The behaviors caused by “I-function” are sometimes trivial like deciding to wait at the yellow traffic light while driving a car. But, because the person has a predispositioned value or belief (on safety and responsibility required for his family or his own motto), he has acted in certain way in his life. And I think his pattern of action based on his values/belief has been recorded in his neurons (like saving a favorite website address so that you don’t need to type it out next time), which ultimately help perform“I-function,” in his own way.
Since we have these motivations (desire of self-actualization and social expectation, etc), our neurons arranged differently depending on individual would cause “I-function” in different ways resulting in different behaviors, and different internal experiences such as the initiation of willful action.
Descartes and Dickinson and the I function
I think the “I-function” kind of helps Descartes’ argument; it is the part of the brain that acts as the mind (in the sense that the mind is embedded in the brain). In Christopher Reeves’ sense, the mind was (what controls emotions and the conscience and such) separated from the brain (what deals with the motor functions), making Descartes correct. Everything that made him “Christopher Reeves,” and was the foundation for his individuality, was in the upper part of his nervous system: what caused him to feel and control. Everything else that wasn’t unique to “Christopher Reeves,” and something that just made him a basic human, was the lower part of the nervous system that controlled his muscles and movements. Then again because the “I-function” is a box within the nervous system, maybe Dickinson is right; after all, thinking is a “pattern of activity across neurons” and what can cause thinking to be different from person to person is the makeup of the pattern itself and how these neurons perform in the nervous system. As you can tell, I’m still trying to work out which theory fits into all of this…
The Juristiction of the 'I' Function
Conclusion to Last Week's Post
Last week I posted about injuries to the nervous spine and how that affects the nervous system and sets of boxes. This week my question was answered in a way. We spent a lot of time talking about how a split of the spinal cord affects the self---making someone present above the slice in the cord.
We also talked a lot about the arrangement of the axons that come off the spinal cord. It seems that although the nervous system is so complex, everything is arranged in a organized way. Even the flow of activity through the neurons is in certain patterns that makes up someone behavior and movement.
The thing I'm still unsure about was in class we spoke about babies being different at birth and then converging to become similar in society. I think this is completely opposite. I believe that babies are very similar at birth, because they have no yet had the influence of society. I believe as individuals grow they diverge from one another, maybe not totally, but they diverge because of nurturing, society, morals, culture, and them just wanting to be different. This can swing back to the I function, where your individual self will make decisions and your mind will see things as it wants to construct them.
The “I- function” makes
The “I- function” makes me wonder more about what is essential to human individuality. We all have the same building blocks but the patterns of behavior are different. In Reeves we saw that we can cut the cables that give our brain access to the rest of our body but Reeves was still there. His, what shall I call it, identity, his self awareness was located above his neck. This makes me wonder how much more cables we can cut without losing the presence of a person. When does the “I-function” lose it’s function? When is our identity destroyed? When are there too little connections for us to function? Not just our physically being alive I mean but for us to be ourselves. Which part of our body is truly essential to our individuality? And also, is there such a part? In a way this leads back to the start of our discussion between Dickinson and Descartes about the human ‘soul’ and weather it is a material part of our body or an immaterial part outside of it.
Leading further into this train of thought it makes me wonder about the consequences of this information for the future. If we find a part of the body, a physical part, that is essential to us (to us being there, our individuality etc.) will we be able to predict the behavior of that individual and maybe even alter it?
Residual Self Image
Ilja's post reminded me of a scene from The Matrix. It happens when Neo first plugs back in after being "freed" and all of his holes/ ports are gone. Morpheus says "Your appearance is what we call 'residual self-image'. It's the mental projection of your digital self." Now clearly the movie makers used this line as a justification for not slapping on unnecessary makeup on all the actors for the whole movie, not to mention all of the characters would stick out like a sore thumb when inside the real matrix. However, this makes me wonder if a self identity crystallizes at a certain point and no matter what experience later in life, you will always think of yourself in a particular way. If Reeves was able to participate in some digital environment would he have thought of himself as paraplegic or able bodied? It seems strange to me that a conception of the self is not constantly updated. People experience new inputs everyday all with some effect upon the "I".
Despite having new inputs daily, a person becomes his or her own reference point. I think this is how we know ourselves from others. This would mean to me that something does crystalize in our minds to make us, us. Keeping in touch with reality and not movie scenarios, is the loss of the "I- function" associated with depression, or other disorders?
Pain
It was interesting to hear about the concept of pain being explained as a simple pattern of activity in one of the boxes of our nervous system. In our diagram of the system I would have thought it to be an input. After all, a person can percive pain without using their I-function. when a person burns their hand they withdraw the hand at the first feeling of pain, before the brain has time to register it. Does pain only be labeled pain if it is a part of the I-function? What about hose who can not feel pain? I know there are some individuals who are born without the ability to feel pain (http://abcnews.go.com/GMA/Health/story?id=1386322) but still have an I-function. What does this do to inform us of pain and how it interacts with the I-function? Is some pain limited to a reflex arc within the sensory nerves and the spinal cord? I would like to learn more about the sensroy process of how a person feels and reacts to pain.
when people have chronic
when people have chronic pain that they can't get rid of they are tuaght to meditate. i'm not sure if it ever works, but i guess it does sometimes because poeple keep doing it. and i've heard monks can make their hearts stop beating.
Also people in comas can maybe feel pain. a study showed that the same pain matrix in both comatose people's brains and healthy people's brains lights up when they are given painful stimuli. i don't know what a pain matrix is, but if comatose brains somehow respond to pain, does that mean comatose people still have an i-funtion somewhere?
I have chronic back pain
1. I was interested in our
1. I was interested in our discussion of paralysis and Christopher Reeve’s ability to move his foot in response to pain. The movement of the foot away from pain is an involuntary process that does not require any signals to reach the upper part of the nervous system. If this movement can be accomplished without the help of the brain, is it possible, that other, more complex movements, could be completed or learned? Take walking for instance; walking requires many parts of the brain including the cerebellum and the medulla. These brain structures are located under the large cerebral cortex and are considered the move primitive parts of the brain. Walking for most people does not require any conscious thought and is accomplished through muscle memory. I know that right now it’s not possible for a person who is paralyzed to walk, but in the future, after millions of years of evolution, humans will not need our brains to walk. We can see from the brains of less intelligent creatures that brain structure has changed considerably over millions of years, so it is not unreasonable to hypothesize that the human brain may also evolve. If we were able to move the boxes required for walking lower in the nervous system, our brains may be able to accomplish more complex tasks because there is more room and energy for these tasks. The ability to complete more intricate processes may be favorable adaptations and be selected upon during natural selection.
2. Action Potential and resting potential are alike in many ways. Both involve the change in charge across a semi-permeable membrane. In a typical cell, there are more potassium ions inside the cell and more sodium ions located outside the cell. In the cell membrane, there are potassium-sodium pumps that help the two ions move from inside to outside the cell without passing through the hydrophobic bilayer. When the cell is at rest, the potassium pump is typically open, while the sodium pump is closed. This allows potassium ions to move from inside the cell to the outside. This movement towards the outside of the cell is known as diffusional force, which is balanced by electrical force, which is pulling the potassium ions back into the cell. So, the potassium ions move out of the cell because statistically, they have more of chance of moving in this direction, but once there has been a net movement of potassium ions, a electrical gradient is created, where the inside of the cell becomes more negative. The potassium ions will then start to move towards the positive charge (electrical force). This movement creates a voltage across the cell (-60 mV)-also known as the resting potential. So, the ability of potassium ions to diffuse across the membrane creates the resting potential of a cell.
"I-function" and consciousness
When we learned about the "I-function" this week, one of the first questions that came to mind was: Isn't the "I-function" same as consciousness?
It seemed to me that the ability to think about oneself and one's actions and thoughts pretty much defined consciousness. Doesn't being conscious mean that you are aware of your surroundings and yourself, which is what the "I-function" is? However, after thinking about it again, I've come to think that maybe consciousness is simply being able to take in all the input signals from the environment and being able to potentially react to them. While the I-function is a part of consciousness--the part that focuses on thinking about how the "I" is going to interact with the environment. Perhaps the "I-function" fits under the larger umbrella term of "consciousness".
More interestingly, I've been looking at a book called "The Mind and the Brain: Neuroplasticity and the Power of Mental Force" which discusses the work of Jeffrey M. Schwartz, who has done work helping OCD patients break their compulsive behaviors. In his book, Schwartz discusses how having patients simply think about behaviors that could replace their compulsive habits decreased the incidents of the patients engaging in their compulsive behaviors. Simple willpower of the brain could change the neurostructures of the brain to break the loop that caused the repetitive compulsive behaviors in OCD patients. This shows that the "I function" could influence consciousness by changing how we respond to our environment (in OCD patients, not responding to compulsion-provoking stimuli with compulsions). So even if the "I function" may be a subset of consciousness, awareness and control of the self are powerful enough to shape the way we perceive and respond to our environments.
"I function" and Athletics
I
"I" and past experience
I am sort of playing devil's advocate here in the sense that I absolutely do not believe what I'm saying accounts for the whole mind and I don't think we will ever be able to pinpoint or understand all of the contributors to the "I." That said, I do think that our personalities, our individual responses to similar situations, our emotional activity, are all highly dictated by autobiographical memory and its neural framework. Memories shape our behaviors, responses and ways of interacting with/understanding the world around us.
The sum of our experiences predict the unique response we have to situations, similar to the idea that sums of observations allow us to hypothesize about the behavior of scientific processes. Past knowledge, both procedural and explicit, and our memories--housed in the hippocampus--are constantly being activated in response to our daily activity and all our inputs (I guess we could say the hippocampus is a box that contains lots of interneurons which continuously filter inputs and outputs).
memory without I
I-function
Self and the I-function
From the discussion in class it seems like the I-function is what we consider "self." Differences in the I-function maybe responsible for each person's unique perspective. To me it makes sense that some actions require the I-function, while other more basic actions, like walking or breathing, do not need the I-function. Everyone pretty much breathes and walks in the same way, using the same muscles. The I-functions can account for differences between individuals. Maybe passing through the I-function box causes people to respond differently to the same stimuli.
If the I-function is our "self" then it must be able fluid to change. As individuals learn/ are influenced by their culture and experiences, the I-function must also change. Also,I don't think the I-function exists as a single palpable area of the brain but a much more complex pattern of activity across the brain. To me, the term I-function is a convenient way a labeling a pattern of activity that is responsible for our sense of self.
"I" Function
Although Webster's use of "I" function was interesting, I was also fascinated that her paper was being used as a teaching aid for the Nashua School District (NH). This information should be comforting to the previous student's preoccupation that our classroom conversations do not intersect with those of other neurobiologists (even if these neurobiologists are high school students!).
Thoughts on I-Function
In class last week, I asked whether or not the "I-Function" is something used among neurobiologists or if the term/concept is just for the convenience of the class. While this may have seemed to be a trivial concern, I think it is important to understand where our class conversations intersect with the larger conversations that neurobiologists are having- especially given that part of the purpose of this online forum is to open our discussion to people outside the classroom. At some point, I hope that the two conversations can merge, and we can feel as though we are all pondering the same questions. I do wonder what the purpose is of developing terminology/concepts that continue to separate us from larger field. Is the aim to propose a new theory? To put complex science into layman's terms?
If we think about the I-function as what's responsible for a sense of causing and experiencing action, I'm curious as to whether dreams are part of it. Do dreams pass through the I-function?I cannot claim to have caused the experience in the dream because it's not an experience I ever really have- and I often don't have control/will-power in my dreams. Additionally, I act in a dream, but do not really act in terms of my physical environment- so is running in a dream an action I can claim to have experienced/caused? We discussed the fact that the I-function is related to, but not the same as, the conscious/unconscious distinction, but I'm interested in learning more about where these two concepts overlap. In other words, if dreams are part of the unconscious, can they also be part of the I-function?
We have established that
We have established that the I-function allows one to say "I can produce movement" or "I felt that." So, Christopher Reeves could not control movement below his neck because his body had been disconnected from his I-function.
We also established that the I-function was only responsible for actions that an individual is aware of. For instance, beginning to walk, or learning a particular skill like riding a bike. Afterwards, one does not need to think about every step she is taking, or which muscles need to move in order to work the bike pedals. These actions, then, did not use the I-function, but Christopher Reeves could not perform them.
Is there another box in the brain that Christopher Reeves' body was disconnected from, then? Or is it simply that because it was disconnected from the I-function, he could not even start the action?
The significance of the "I-function" box
emotions and the I-function
I found the I-function
I found the I-function particularly interesting today because, as we were discussing the "where is Christopher Reeves" phenomenon, I thought about several other applicable cases. Could it be that, because in individuals with autism (who some experts have attributed to having problems with sensory functions), also be placed in the "where is this individual with autism located?" Could it be that autism is an anomaly, like the Reeves anomaly, of the I-function where somehow, some cords got tangled/cut/rearranged and they exist solely on inputs that are only really half-received? Perhaps these individuals can "think" all they want that they enjoy the sensation of being touched, but that "thought" has nowhere to go, or somehow gets lost along the way through the I-function. Or, when they are touched, the output gets lost among the cords and, because their nervous system doesn't know how to process the information, the I-function goes a bit haywire? There are many interesting analogies that I think could come from this.
Practicalities
Whenever I thought of the nervous system prior to this course I assumed that yes, it was a powerful and yes, it does control everything on my body but I never realized the set up was so practical. The fact that the parts of your body correspond to a certain section of the nervous system in an corresponding and relative manner never occurred to me. Nor did I pay much attention when I walked, talked, sat and stood about just how my body was accomplishing these requests. I though that my arm lifts because my muscle lifts in, not because a pattern of activity in my neurons caused it to. The fact that the nervous system controls so much was not a surprise, but it was overwhelming to have it all stated and pointed out. The issue of Christopher Reeve made me question the permanence of severing the cord between the brain and spinal cord. If it could be reattached or sewn back together isn't it safe to assume that a person could potentially walk again since both systems are still functioning, albeit separately?
In class today, we did a
In class today, we did a thought experiment about the relationship between thought and action. The observations from our experiment led us to conclude that thinking about an action and performing an action are different. Thoughts can be completely dissociated from inputs and outputs in the nervous system. I am curious about to reconcile our conclusions with the concept of motor imagery and athletic performance. Basically, athletes and researchers have found that visualizing a task, in advance, enhances performance. For more on this topic see
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