Biology 202 Neurobiology and Behavior Spring 2002

What's your reaction to the phenomena of quadriplegia as described in class? Is the addition to our model of an "I-function" box appropriate/useful? Why or why not? What new problems/questions does it raise?

If most neurons are in fact just located in the larger box which is the nervous system, then what does that say about vertebrates and invertebrates? Are they really that different? Although invertebrates lack the cerebellum, midbrain and forebrain as such fact was mentioned in class, the data presented insinuates that they're possibly not that much different from vertebrates.They too have a collection of neurons which extend throughout their bodies and which I would assume serve the purpose of input and ouput functions.

We've also concluded that there is an infinite number of ways in which neurons can be assembled for input and output function. Thus, complexity is further brought as these neurons can differ not only arrangement but manner in which this information is processed and sent back out.

The question about how many boxes are there is unanswerable. I do think there are a finite number of boxes but it is constantly growing as we acquire more knowledge and come across many more experiences day to day. So not everyone has the same number of boxes or the same “type” of boxes and this makes us the individuals we are.

On a separate note, I think it's important not to overestimate the similarities between the brains of different species. While it is undeniably true that we share the same building blocks with all vertebrates, we are still drastically and fundamentally different. We may have all the same parts, and our brains may all appear very similar under high magnification, however, the behavior between any two species is completely different. Even with humans, where the biology is nearly identical from one person to the next, behavior can vary dramatically. Thus there is obviously something immensely important in the little differences that exist. Though my brain may look very similar to any other person in this class, there has to be some very significant differences to account for our behavioral, intellectual, physical, etc. dissimilarities (assuming that brain does indeed equal behavior.)

As usual, you're free to write about whatever thoughts you've had this week, but if you would like something to get you started:

What's your reaction to the phenomena of quadriplegia as described in class? Is the addition to our model of an "I-function" box appropriate/useful? Why or why not? What new problems/questions does it raise?

Do we really need something outside the nervous system to truly discover what we are? I think there is more to the nervous system than just the nervous system itself. But is everything really a function of the brain? Again, we act differently under different circumstances and at different times.

Does the “I function” box have access to all information? There are always different inputs coming in and different outputs coming out. How does the "I function" fit into consciousness? Consciousness alone is very hard to define. Could consciousness be defined as the experience of being oneself and that oneself being reflecting in a sub-system of the nervous system (which would be the box).

There is a difference between behaving and being aware. Is the “I function” accounting for all of our changes in experience? Or does the "I function" change when we change? There are parts of the nervous system that can be doing things without us actually experiencing them. Ones feelings do change with time. But does the self actually change everytime there are nerve cell changes?

What about when your foot “falls asleep”? You know your foot is there, but it doesn’t feel the same. Also, many people are afraid of getting shots. My friend fainted when he got a needle injected into him. I highly doubt it was the pain of the needle going into him, but more of just the sight alone of a sharp object. Part of human experience and awareness is learned. People look toward the reactions of others. A wound that looks terrible, may not really hurt, but if people look at the injury in horror, the person may start to “think” that it does hurt.

Christopher Reeves has to feel a 'sense' of loss. But is that 'sense' of loss different than actually feeling pain if someone would pitch his toe? Is that a different 'feeling'? He would know that under normal circumstances (before the injury), that someone pinching his toe would usually elicit some type of pain.

Since all of the chemical materials that make up our bodies are the same, what makes us unique is that which we have inherited, experienced and learned. The axonal connections that create the sensory and motor systems also make neurotransmitter synaptic connections that allow us to store, file, and remember. The ability to synthesize what we store, retrieve it, and make decisions about it (the output) is what makes us emotional beings. Are the emotional connections the I-function? Is it the I-function that allows us to be different from other creatures made of the same chemical material?

When we pinch Christopher Reeves' foot, it will jerk, yet when asked whether he felt pain, he does not.
But, then how do we know he is Christopher Reeves? We ask him, and he responds.

This example made me think about ethical debates in medicine. For example, the debate about the use of stem cells.
There are many people who view the use of stem cells as cloning. Hurting an individual being. But one could argue that the I function is not really there.
Worried about the stem cells potetial for life.

OK

When we pinch Christopher Reeves' foot, it will jerk, yet when asked whether he feels pain, he does not.

But, then how do we know he is Christopher Reeves? We ask him, and he responds.

This example made me think about ethical debates in medicine. For example, the debate about the use of stem cells. There are many people who view the use of stem cells as cloning. Hurting an individual being. But one could argue that the 'I function' is not really there. The organs are independant from the brain. One is not really killing a human.

And then what about abortions? If aborted before the brain begins development...is it really murder? I mean, if what you are killing has no way of processing what you are doing?

Well, I guess my thoughts don't take into account of the potential for life. But this is what I have been pondering...

My results yielded one conclusion, I need to narrow down the topic further. I just find that while the subject is compelling its tied to at least 25 separate issues. I have not yet decided if I would like to pursue this as a paper topic, but I am certainly interested in it for my own knowledge.

For the first paper, I am reading about the "mind-body" problem, and the biggest hurdle in takcling this subject is the idea that this is a problem. It seems to me outdated: as we look at a PET scan of a functioning brain, and study the brains and behavior of those who have suffered injury to the brain, be it from physical trauma, pharmacological excess, genetic defects, or extreme emotional stress, it appears evident that consciousness is a product of the neural connections in the brain.

What I suspect troubles current thinkers about the mind-body problem is that humans cannot create consciousness in another brain -- even with healthy raw material, we can stimulate neurons electronically, but we cannot get them to stimulate themselves. We do not know how to get the machine up and running. As a result, we are inclined to believe that consciousness, the "I-box," must be more than the sum of its physical parts.

Yet if we believe that the nervous system controls the movement of a leg, why not the decision to move the leg and the perception of that movement? What difference is there between the two that requires movement to be relegated to the nervous system, and consciousness to be elevated above it?

"Not all functions of the Nervous System depends on Christopher Reeves being there" (Grobstein)

After weeks of pondering the soul over brain=behavior phenomenon,
Feb. 7th's class enlightened me in many ways.
It makes perfect sense that the nervous system is independent of state of mind. If Reeves, had been a vegetable, his nervous system would have continue functioning independently. If he had also had a mental breakdown or suffered from psychosis, Reeves may have "been gone" but a majority of his NS would have been functioning.

The latter examples, however demonstrate that we are more than our nervous system. Quality of life as we see it, depends on the functioning of the input/output brain boxes. When these brain boxes fail to properly transmit information, the individual is no longer "here." Yes, Reeves may have had an interruption btw his brain and spinal cord. However, he will continue to experience life on an emotionally sensory level which would have been impossible if he had been a vegetable.

On a different note: Although Dickison states that the brain contains me and the sky, she speaks of the capability of the brain.
I believe that the individual's experience and reality can also manipulate the brain: So what's real to me may not be to you

The question concerning "where is Christopher Reeves" is also very interseting. It makes one wonder whether or not "christopher Reeves" is his entire body, or only his brain. From what we learned in class on Thursday, I am prone to think that Christopher Reeves is his brain and that his body is merely a capsule for his brain to function in.

But Grobstein's comment on the nervous system not needing Christopher Reeves to be there for some functions to happen makes one question the brain=behavior theory. If the brain was responsible for all behaviors, and Christopher Reeves was his brain with his body being a capsule, if some functions can occur without Christopher Reeves "being there," then doesn' that mean that the brain isn't responsible for all behaviors??? And the questions continue....

The discussion of Christopher Reeve brings up many ethical issues. In class we decided that Christopher was contained inside the upper part of his brain and that his nervous system continued to function below his injury without input from his "being". I think this is very interesting because it helps us define where an individual's being comes from. Many have become involved in heated topics over things such as brain death and what living actually defines. Does living mean a continuation of one's nervous system or does one's "being" have to be aware to be considered alive? If the first is true, then even when the "being" seems to die, the nervous system still functions, much like Christopher's reflexes and how does one make ethical choices over this.

I once saw an interesting program depicting sufferers of post-war syndrome. They were incapable of responding (aka making behavioral outputs), but were perfectly aware of what was going on around them. Without complicated machinery, it would have never been known that their "beings" were indeed still alive within bodies unable to respond. I wonder how people would classify them. As a cousin to two severely retarded children, I find this issue to be very personally. People have made comments that they do not understand what is "really going on", including Mr. Politically Incorrect Bill Maher himself, who compared them to "mere animals". I refuse to believe that just because their behavior is different to us means that they are any less "aware".

The I-function is the basis of our will to control ourselves or our behavior. Watching Kung Fu movies, I was amazed at the men who would embrace scolding hot iron pots to brand a symbol of a dragon on their arms. From personal experience, whenever you feel something hot, you have an initial reflex to move away. However, these men overcame that reflex with their will, which the I-function accounts for. This example of will overcoming intial reflexes is also present in tattooing. The only questions with the I-function are how it works? What is it composed of? Is this the part that is referred to as the "mind" in the brain? Is the I-function only influenced by personal experience? Is there a commonality in the I-function that everyone uniformly has? How different is my I-function compared to another's? How large is the I-function in the brain (size) and how important is its role in everyday activity?

Just some food for thought on the I........

I have some question, perhaps they will get answered by the end of the semester...

Even though Chris was able to move in a reflex scenario, he was not able to move his foot otherwise. This is because there is a large difference between the normal nervous system reaction and the reflex movements. The sensory and motor neurons are connected to the spinal cord which is below th point of paralysis. Therefore, the normal sensory input was meaningless for it was not connected to the brain. This would explain the reaction that was discussed in class. One of the problems with my conjecture is that I am not certain where the reflex center (if there is one) is located.

What is curious about quadriplegia is that the sensation ability is lost. Here, the term sensation must be seen in relation to I-function. Sensation implies awareness, becoming a more mental than physical term. Hence, there is a definite boundary between physical death and mental death. One can essentially receive input and involuntarily respond via output, but the process is removed consciousness.

I help to take care of a gentleman who suffers from a very rare brain disorder called progressive supranuclear palsy (PSP). The actor Dudley Moore also suffers from PSP and has helped to fund research on the disease. To me, this is an even more devastating problem than quadriplegia. An individual suffering from PSP experiences gradual loss of function, first speech, ability to swallow, etc which then progressively leads to almost total paralysis. The person I am speaking of developed his first symptoms about five years ago and now is limited to subtle finger movements and occasional control of facial expressions, such as lifting his eyebrows. To blink, he must concentrate on forcing his eyes closed and then forcing them open again. We must frequently remind him to blink.

What is so tragic about PSP is that the mind is not at all affected, and capacity for sensation is maintained. However, output functions are almost completely suppressed. If I were to pinch this gentleman's toe, he would indeed feel it but he could not express that, or even move his foot away.

In an individual with PSP (as well as quadriplegia), the box model would be quite inefficient in describing input/output relationships. In PSP, output is limited to the realm of the I-function, or awareness. In quadriplegia, input/output is not even experienced by the I-function. These are very different instances. Is it better to maintain some normal input/output functions as in Christopher Reeve's case, or to be fully aware of all input yet have very, very limited output capacity?

A few unrelated questions:

Is the I-function another namme for the mind?

How can we explain the fact that although Christopher Reeves suffered severe injuries to his spinal chord he has been able to regain some of the functions that had been previously lost as a result of his injury?

Remember how Dr. Grobestein can not see on the right side because of the damage on the left side of his brain? Well, I think the conclusion we came to with that was the stimulus was there, but he did not think that he saw it, even though he did and even though he pointed to the area of the stimulus. So if Reeves was stimulated, and he reacted, acted or behaved to it, then how can that not be behavior just because his I-function was not there? This just seems like a different type of behavior.

If behaving is to be aware of behaving, then what about those who act out their dreams and sleep walk. Those who sleepwalk are not totally there or, their I-function is not there, just like Reeves or Grobestein’s isn’t. But how is that not behavior?

When there is brain damage, do neurons attempt to re-establish the former connection or try and establish a new connection? Is that what happens when some who are paralysed eventually get healed? Perhaps that is the method we need to develop in order to heal those who are parapalegic.

Consider Steven Hawking and his crippled body. Despite his disease, he is still brilliant and although his body is withered, he is still Steven Hawking. His brain still functions in a most remarkable way and we can still recognize him although his voice and body are unrecognizable. The essence of the man is his brain, and since the brain controls everything, brain equals behavior even when there is no behavior other than the behavior of the brain. When all behavior ceases, so does the brain. If the brain can hold the sky and all that is in it with room enough for the "I", than the brain’s capacity is only limited by the scope of the imagination of the person who houses the brain.

The general populace throws around terms such as shallow coma and deep coma, without much regard for the fact that there are numerous clinical features of the different stages of a "coma." So, given someone who is unconscious for an extended period of time, when do we begin to stop thinking that they possess an I-function? I have had the opportunity to witness the management of numerous such patients with a range of neurologic conditions in the medical intensive care unit of a major academic medical center. Many of the physicians I worked with had differing views on patients with brain damage. Some were quick to assume that comatose patients ceased to have a sense of self and the ability to have any awareness of themselves or the outside environment. Still others cited how the "locked-in state" (patients can process events and stimuli around them, but cannot effect a voluntary response to them) is mysterious, and one can never be certain of exactly what activities are going on in the brain.

It seems that all of this begs the questions – when do you stop being you? Are you really there if you are in a persistent vegetative state? Are quadriplegics like Christopher Reeve really there? Can you actually cease to possess a "self" after a certain degree of brain injury? Essentially, patients in the persistent vegetative state are on autopilot. There is no one manning the controls, but the plane keeps flying. This does not mean to say that the possibility for patients with even severe brain injury can’t be aware of what is happening to them. There are a range of behaviors that do not require you (the psychological construct of you) to be there, but they require the biologic and physical you. Some patients with no hope of ever leading a productive life again who are teathered to a ventilator can open their eyes, move them spontaneously, and cringe when tested with a deep pain stimulus, but for all intense and purposes, they are not there. In the ICU, I observed this to be a very difficult thing for family members of patients to accept. They would look a loved one in their eyes, see them blink, and swear that he or she was in there somewhere. They saw such actions as things the patient himself or herself was doing – they saw this as evidence of free will – however, it wasn’t really "him" or "her" in the sense they thought it was.

When someone has ceased to be able to carry out higher order processing, have they lost their I-function? Some scientists argue that even when there is just the slightest trace of brain activity, one can never be certain that there are not processes going on elsewhere in the brain that we just don’t know about. The mere fact that there has been intense debate about what constitutes brain death is a testament itself to how muddy and complicated the idea of brain = behavior is. A person who is suffering from a drug overdose can temporarily exhibit the same clinical findings as someone who has had severe irreparable brain damage. However, the overdose victim can regain mental status fairly quickly.

It is useful to add the I-function to our model since it makes sense from the observations of Christopher Reeve’s condition that this consciousness is probably located somewhere in the brain (although we might want to get more data that supports this notion). However, adding the I-function box raises many new questions. For example, what is the box made of? Is it an area in the brain like the amygdala and thalamus or is it neuronal activity in the brain? What behaviors is the I-function (i.e. consciousness) capable of producing – is dreaming a state that the I-function moderates or is dreaming controlled by another area of the brain? Are insects conscious? These are just some of the unanswered questions that we might want to address when we modify our model.

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