Biology 202
Neurobiology and Behavior
Spring 2003

Forum Archive - Week 3

Have a look back at our current "model" of the nervous system. That model seems to be able to account reasonably well for two aspects of the behavior of quadriplegics (Christopher Reeves, for example): the observation that pinching the toe leads to food withdrawal, and the observation that when verbally asked to move her/his foot a quadriplegic says she/he can't.

Two additional relevant observations are: the quadriplegic reports an inability to move the foot at all, and reports no experience of having the foot pinched. Can we make sense of these additional observations using the current model? If not, what modifications to it might make it less wrong?


Name:  Paul Grobstein
Username:  pgrobste@brynmawr.edu
Subject:  week 3
Date:  2003-02-06 13:42:46
Message Id:  4453
Comments:
As always, you're free to write about whatever the course has caused you to think about this week. If you're in need of something to get you started ...

Have a look back at our current "model" of the nervous system. That model seems to be able to account reasonably well for two aspects of the behavior of quadriplegics (Christopher Reeves, for example): the observation that pinching the toe leads to food withdrawal, and the observation that when verbally asked to move her/his foot a quadriplegic says she/he can't.

Two additional relevant observations are: the quadriplegic reports an inability to move the foot at all, and reports no experience of having the foot pinched. Can we make sense of these additional observations using the current model? If not, what modifications to it might make it less wrong?


Name:  Rachel
Username:  rsinger@brynmawr.edu
Subject:  Reeve
Date:  2003-02-06 12:46:39
Message Id:  4451
Comments:
In class today, we learned that Christopher Reeve does withdraw his toe when it is pinched, yet if someone tells him to move his foot, he cannot do so. This is due to the fact that the input and output are located in different areas of his CNS: input in brain - and foot-moving output in the caudal end of the spinal cord. Because the connections between these two regions of his CNS were severed, Reeve can only respond if the areas stimulated are in the same region of the CNS (he withdraws his toe (input generated in the caudal end of the spinal cord), since the same caudal area of the spinal cord is stimulated to yield an output).

If Christopher Reeve's toe is pinched, and someone ask him if it hurts, he does have the ability to say no. Then it would make sense that the input and output areas for processing your words and his own pain response are both located in the same area of the CNS. In addition, the fact that one tells Reeve to move his foot, yet he cannot do so but RECOGNIZES that he cannot do so demonstrates that the recognition of his lack of foot motion is indeed an output from the same area of the CNS (the brain) as the input (his processing your words telling him to move his foot). He cannot, however, move his foot because this output is not from the brain, but rather from the caudal end of the spinal cord.


Name:  Katherine
Username:  klafranc@brynmawr.edu
Subject:  defining the self?
Date:  2003-02-06 16:52:45
Message Id:  4458
Comments:
It is very interesting—Reeve reports, "I cannot move my foot"—but his foot does move— So, what is this mysterious "I" ?

These observations seem to mean that that there is a distinct and limited definition to what Reeve—and other people—consider to compose the 'self.' The idea of self in this case seems to depend upon the detection of input into the brain, rather than to the lower parts of the spine.

Does this then explain the requirements for consciousness? Reeve is not conscious of the feeling of motion in his foot. He does not attribute the caudal region of his spine to 'self,' because even when motor neurons caused his foot to move, he claimed not to have caused this movement. He was not aware of making a decision for movement.

The attribute of 'self' in this case seems to take on a privileged place in the nervous system, since not all parts of the system are included. First, the 'I' seems to live in the brain and not the spinal cord. Second, it seems to require a distinct decision making process to occur that is somehow different, or at least perceived differently, than a process in the spine that results in the same behavior.

Could the boundary between what we consider 'self' vs. 'non-self' be simply the interface of brain and spinal cord? That seems too simple to explain everything. And what about 'consciousness'— we might say that this is just the brain's ability to make decisions and to be aware of this decision-making process. but again this explanation seems too simplified, and leads to yet more questions (i.e., what does it mean to be 'aware'...how does this apply to sleep, dreams, etc...)
When do we as humans acquire this perception of 'I', and which other organisms possess it-- ?


Name:  Tiffany Litvine
Username:  tlitvine@brynmawr.edu
Subject:  Thoughts
Date:  2003-02-06 19:12:08
Message Id:  4465
Comments:
I thought today's discussion about quadriplegic, Christopher Reeves, was very interesting. I had no idea that quadriplegics were able to move in any way, even when pinched. I was quite suprised although it made sense once we went over how the nervous system functions.
I think that it makes sense that a quadriplegic reports an inability to move his foot when asked or to feel a response when pinched. The nevres that connect the brian to the spinal cord have been severed. Therefore quadriplegics are unable to make their foot move since they cannot send the message down the motor neuron responsible for the movement of the foot. Nor can they feel the pinch since the sensory nerves are no longer able to transmit the message back to the brain and allow it to feel the pinch. Hence I feel that the statement is correct according to our current model of the nervous system. There cannot be an output if the boxes that generate the output are not accessible to the box that is initiating the action.
This discussion concerning quadriplegics also led me to wonder how their bodies are able to function if they cannot feel what is happening to it below their neck. For instance how does homeostasis work if the quadriplegic cannot feel temperature changes? Is the body still capable of knowing it has eaten without feeling it? I wonder what type of body functions a quadriplegic is capable of maintaining on his/her own, if any at all? Is the brain still capable of regulating the body if it recieves no input of changes within the body?
Name:  Elizabeth Damore
Username:  Anonymous
Subject:  The Power of Suggestion
Date:  2003-02-06 23:20:26
Message Id:  4468
Comments:
I work at a coffeehouse, and the other night we ran out of regular espresso right before closing. Since there wasn't time to get more coffee, we served decaf espresso to customers instead without telling them the difference. As I had read that the effects of caffeine are mainly controlled by the power of suggestion, I was interested to see how people would react to the switch. As expected, not many people noticed the difference. Could it be that our brains can control how our nervous systems react to chemicals? It doesn't seem possible, but I've read many "scientific" accounts of people controlling their health through placebos and even such things as positive thinking. Surely, the connection between the brain and the nervous system is much more complicated than I had thought.
Name:  Neesha
Username:  npatel@brynmawr.edu
Subject:  
Date:  2003-02-08 15:21:29
Message Id:  4481
Comments:
This is a question regarding last weeks discussion that I had been pondering over. As I couldnt add this to the previous forums, Im adding it to this week's postings.

Its really hard to beleive how "fluid" the brain is and how closely connected brain and behavior are. Never before had I thought that peoples brains could be different. One of the examples someone mentioned from class was that of a serial killer. I can beleive that a part of the brain could change if a normal person became a serial killer, but what if the serial killer after years of committing crimes, decided to become a good person. Would the brain undergo some change again? Maybe back to its original state?? This would imply that the brain is always changing, right?


Name:  Andy Greenberg
Username:  agreenbe@haverford.edu
Subject:  An Emergent Property
Date:  2003-02-08 17:32:09
Message Id:  4482
Comments:
Katherine's discussion of how parts of the body can be split from the "self," and the ensuing questions about the physical location of the "self" and "consciousness" in the nervous system grabbed my attention. The question of where consciousness exists is a huge problem of philosophy. Descartes said it belonged in the pineal gland. (so he's obviously given his wrong answer for the week) Many modern philosophers who consider the question believe that consciousness cannot be reduced to a physical object with a location.

The philosopher John Searle writes of a thought experiment that tests the sort of bizarre, extreme version of Christopher Reeves's unconscious toe movement. He posits a situation in which a person's brain is replaced part by part with pieces of silicon that function exactly as those parts did. Now after the brain has been completely siliconized, what happens to the man's consciousness? There are three options: A. It exists just as before without change. B. It no longer exists C. It exists, but in such a state that the it is totally epiphenomenal, hovering somehow outside the brain with no causal powers.

The most likely proposition seems to be letter A, that the consciousness is not effected, because it seems that, despite Descartes' ridiculous ideas, there is no specific part of the brain that contains consciousness. It is an "emergent property": mental states seem to arise somewhat magically from a collection of physical objects in a certain configuration. But at the same time, certain functions of the nervous system can indeed be cut out of the realm of consciousness, as Mr. Reeves's foot shows us. Thus, the question becomes, from what set of elements in the body does consciousness "emerge"?


Name:  Danielle McManus
Username:  dmcmanus@brynmawr.edu
Subject:  
Date:  2003-02-09 09:18:58
Message Id:  4483
Comments:
Looking at the example of Christopher Reeve and the ability to move his toe when pinched, maybe the input/output model we've been examining could be revised somewhat to accompodate instances such as Reeve's.

If our model shows behavior as an input which travels through different boxes in the brain to be discharged as a resulting output, what accounts for reactions like Reeve's toe-jerk which don't or can't reach the brain? Maybe the model should include subsidiary boxes which follow the input/output theory, but operate outside of the brain.

These boxes would have direct paths from the input to an intermediary box outside of the brain (in Reeve's case, the box would be at the caudal end of the spinal cord) and out as an output back to the source of the stimuli. These boxes would be like closed-loop circuits designed for quick reaction to inputs which are dangerous enough to require reaction more quickly than could be given if the information had to be transported all the way to the brain, processed, and sent all the way back.


Name:  geoff
Username:  geoffpollitt@hotmail.com
Subject:  free will...
Date:  2003-02-09 11:50:12
Message Id:  4486
Comments:
I am still stuck on the idea that serial killers have different brains than the rest of us. why do i believe that assumption so strongly (i do, don't i?), when there has been no real evidence on the matter? as far as i can see, it because i don't want to think of the alternative. it is scary as anything to think that my brain may be exactly the same as ted bundy's. i also would like to think that i have free will, and that because i know the difference b/w "right" and "wrong" i will stay on the straight path my whole life. but here is an example that gives me a lot of trouble:
it is easy to demonize serial killers in our society, and say that there was something wrong about them (chemical imbalance from birth, or bad family problems, some trauma that set them off), that i don't have to worry about in myself. so what do i do when i find this ugliness in "normal" upstanding citizens. i am not talking about ted bundy, who except for instances of killing women in brutal and disgusting ways, was known to be a pretty straight up guy.
i am thinking of various examples of war studies i have read (this comes from the book, 'Male Fantasies' by Klaus Theweleit). the one that stands out is a story of senator bob kerry. i don't like politicians as a rule, but kerry is generally thought to be a good guy, and may be a presidential candidate in the upcoming election. the book (theres a bunch of internet articles on it too, i just found this one: http://news.bbc.co.uk/1/hi/world/americas/1298289.stm) talks about how during the vietnam war he was involved in one of the many slaughters of a civillian village, much like the 'my lai massacre', but less well known. this was not an uncommon occurance during vietnam (from what i gather), nor has it ever been during any war by any side of the fight (allies do terrible things even when they are fighting against nazis). there are many of examples of men doing things that are as terrible as that which ted bundy did, but during a time of war.
what i like about the kerry example is that he comes back and is a war hero and lives a normal life. we can say that he had trauma during the war that changed his brain to allow him to do something so terrible, but how then do we account for the fact he returned and has lived a life since that puts him in line to run for president?
what i am trying to say is that i don't necessarily see our brains as having THAT much to do with our behavior on any kind of relevant level. i undertand that we each have a different makeup when we look close enough, but then shouldn't we be able to react to situations like kerry's differently? and every now and then, someone does, but for the most part, men are predictable in war time situations. the man who didn't participate in my lai or spoke out about it after was an exception, and for that we don't know about most of the instances. put a given number of drastically different brains in that environment and you don't end up with a drastically different number of behaviors.
maybe war is a bad example because i can point to the intensity of the situation and say it is not real life. so then i look at haverford or bryn mawr, and at a larger level are we all doing that many different things? i know technically we belong to a different set of clubs or sports teams or choose different majors. but how relevent is that? is that the free will we keep talking about, that we each have chosen our own major study? because on a less drastic level, i see us as being very similar to my analogy of a war time situation. put a given group of students (selected to be diverse) together for four years and you will come out with basically predictable results. if it were not so, our colleges could not run as smoothly as they do.
if our bio class did not have a make up where a few people speak and most stay silent, and where the professor controls the pace of the class (and subsequently my free will) and we follow accordingly, it would not run very well. at the same time, we spend class time telling ourselves that the brain is a mystery because of this idea of free will?
it makes sense to me that i still believe in free will, life would not seem very worthwhile if i did not believe i had some say in it. but what is the free will we are talking about? i get it that we have very different nervous systems, but if we all go in with that and in any given environment basically play a given role, what does it matter?
Name:  geoff
Username:  geoffpollitt@hotmail.com
Subject:  more....
Date:  2003-02-09 11:55:14
Message Id:  4487
Comments:
sorry for writing so much, and now for more, but i wanted to post up this website we were given in my perception class. click on the links on the left to see the illusion (there are instructions). my favorite is the koffka ring, b/c unlike the illusions about our blind spots (where we make a dot disappear or connect a line) or the ones where you stare at an american flag that fades quickly, i can stare at a ring that i know is always the same color, and it will never look the same to me. the world is not what it seems...

http://www-bcs.mit.edu/gaz/


Name:  Amelia
Username:  aturnbul@brynmawr.edu
Subject:  
Date:  2003-02-09 14:22:21
Message Id:  4490
Comments:
I've been thinking about the Christopher Reeves example of the nervous system since class Thursday and been mulling the idea over the weekend. After reading the postings of my classmates, I thought about the situation some more and came up with a few ideas/questions. Reeves' spinal cord was severed and therefore the signals that come from his brain cannot be sent below his neck and the signals that come from below his neck cannot go to his brain. If we believe that the seat of consciousness is in the brain, Reeves is correct when he cannot feel his foot being pinched. The input cannot travel to his brain and say, "Hey! Someone just pinched my foot!" However, as the somas of the nerves in his foot are based in the caudal end of the spinal cord, the signal goes to them and in an involuntary response, Reeves' foot pulls away.
I've been thinking that if the seat of consciousness is in the brain, it can be fully true that Reeves can say that he cannot move his foot. He cannot think and make his foot move, consciously or unconsciously. His foot can only move in response to outside stimuli, and not stimuli within himself.
Name:  Kate Tucker
Username:  ktucker@brynmawr.edu
Subject:  
Date:  2003-02-09 14:23:13
Message Id:  4491
Comments:
I can certainly relate to the need to put serial killers in a different category than the rest of us. I feel much better about myself if I know that I am in some way biologically different from someone who murders people. Its an interesting twist on free will. I would imagine that even people who believe very strongly in free will still want to hold onto something more than serves as a separation. One of the things that I thought was interesting about our discussion in class about people who have different brain chemistries is that we made a point to distinguish between different groups of people who display different behaviors, but I wonder if the differences in brains are really large enough between different groups that they would even be detectable. What I mean is, we have all agreed that each one of us in this class has a different brain. But are the differences in our brains ones that we could detect and study? And do things that we perceive as great differences in behavior translate to great differences in the brain? I was reading a Scientific American article earlier "Why? The Neuroscience of Suicide" which mentions at one point that early childhood experiences, such as child abuse, can lead to altered brain chemistry. (Just so you know, that's not the main focus of the article, but it is interesting so I put the link up...) It seems very plausible to me that although people are born with different brain structures, the main differences may result from changes that have occured over the years. Although serial killers' brains may be different from mine, perhaps some change could take place in my brain from some event I experienced that would induce me to go on a killing spree. Well, I'm not sure I believe that...but its possible.
Name:  Nicole
Username:  nmegatul@brynmawr.edu
Subject:  
Date:  2003-02-09 15:12:26
Message Id:  4493
Comments:
Geoff's statement: "put a given number of drastically different brains in that environment and you don't end up with a drastically different number of behaviors." got me thinking.
It is true that few humans share the same or even nearly similar environments on the scope of the entire planet, and over the span of human history. Still, cultures and standards of acceptable or normal behavior do tend to exist among people of similar environments, for example taste in food, clothing, lifestyle, livelihood, choice of leisure activity, language and manner of interpersonal relationships are some examples of behavior that can be more common among members of one environment/region than another (like from a hot desert of Africa to a freezing tundra of Alaska to the busy streets of New York City). However, within one of these environments, almost no two humans really do share the same perspective/environment. Differences in upbringing, even within the same household, can drastically impact future behavior of a person. This sets up the scenario that all humans will behave differently since they all have a background of different experiences on which to base their current behavior even when faced with the same situation. To an extent, I think this is true but on larger scale events, like Geoff's example of a war, even these people from different environments/backgrounds exhibit similar behavior. Behaviors overlap and are shared among very different people. Although at first it may seem to contradict it, these ideas support our model that similar brain structure=similar behavior because humans all have similar looking brains (more similar to each other than to say a monkey's brain) which would suggest shared "human instincts" and other similar behavior, yet on a micro level, it may be possible to detect minute differences in the brain or chemical makeup which would support differences in behavior between humans. With more class and forum discussion of examples, and after looking into Scientific American articles about brain mapping and genetic brain imaging, I feel that our the model of similar brain structure=similar behavior is becoming less wrong each week, as the model is still able to explain how humans can share similar behaviors at times while also exhibiting very different behaviors.
Name:  Jen
Username:  jhansen@brynmawr.edu
Subject:  functions of neurons
Date:  2003-02-09 15:21:16
Message Id:  4494
Comments:
As a result of our class discussion, we have learned that the neuron is the functional unit of the nervous system and is specialized for transmitting signals from one location to another. I have begun to ponder the possible alternatives that could occur due to blockage or maybe some type or variation of damage in the synapse region. I refer to the space between the presynaptic and postsynaptic membranes as the synapse region. I also ponder if there are any particular environmental reasons that could affect the effectiveness of the chemical synapse. The last question that I pose is how a doctor or scientist could diagnose a blockage or destruction in particular neural pathways.
Name:  Michelle Coleman
Username:  mcoleman@haverford.edu
Subject:  RE: Functions of Neurons
Date:  2003-02-09 16:28:48
Message Id:  4496
Comments:
The idea of pinpointing a specific mal-function or blockage at the synaptic clef is a bit far thrown. While there are existing forms of receptor pharmacology, we have yet to zero in on any specific neuron. What many scientists have done and continue to do, however, is look at the larger pattern of behaviors of neurons in a specific area. By using drugs which act similar to the messages passed between neurons (Neurotransmitters and Hormones) and tracking it's specific journey through the clef, we can speculate on how normal messages might be transmitted.

I think the idea of environmental (outside world) stimulus effecting neurotransmission is very likely. If our Central Nervous system is composed of the many boxes we have proposed we might expect environmental stimulus to have a domino effect, reaching and affecting every box. I think that the larger question here however is which effects which more or less, or if there is a one to one relationship between the anatomical/neurological environment and the outer-body environment in regard to behavior change.


Name:  Clare
Username:  csmiga@brynmawr.edu
Subject:  
Date:  2003-02-09 19:41:35
Message Id:  4497
Comments:
One thing that we discussed in class that really bothered me was the idea that there is something in a serial killer's brain that is different from mine and that explains why his behavior is different. I am not arguing that this is untrue. However, didn't we already state that every individual's brain is different and therefore every individual's behavior is different? Then how can we look in a serial killer's brain and say- ah ha! THIS is the part in his brain that is different from everyone else's so it MUST be what is making him be a serial killer. In fact, since everyone's brain is different, this could just be another difference that makes him the individual that he is and has nothing to do with his serial killer behavior. But then again, in other mental illnesses, if that's what you could call them, even though every individual is different and acts differently, there are always similarities in the way that they express certain illnesses, such as depression or eating disorders. Therefore, even though our brain and our behavior ARE different, since I do believe that the foundational way that brains work are similar, does this mean that you CAN open up a brain and find within different brains similar similar conditions related to these illnesses despite the various environmental, social, and biological factors that play into causing these illnesses?
Name:  Cordelia Stearns
Username:  cstearns@brynmawr.edu
Subject:  serial killers, morals and such
Date:  2003-02-09 21:13:15
Message Id:  4498
Comments:
Hmm. Well, while it may be nice to think that serial killers are BORN with different brains than the rest of us highly moral folk, I tend to think that environment alters brain chemistry to a point where something like murder becomes a viable option for people. There was a point in the seventies when amygdalectomies were performed on prisoners to calm them down. For people that don't know, the amygdala is a tiny part of the limbic system attached to the end of the hippocampus that is thought to control many things, namely emotional memory and anger, fear, and rage. It is thought that the frontal cortex puts a sort of check on the emotionality of the amygdala, and keeps organisms from being fearful and enraged constantly. This is why when damage is done to the frontal lobe, people's personalities change to be more aggressive and violent, and less friendly; they no longer have this check. Experiments where the frontal cortexes of monkeys have been damaged have found the monkeys to be fearful, violent, and ready to attack. Likewise, experiments where only the amygdala was removed found the monkeys to be extremely people-friendly, fearless, and tame. Anygdalectomies are not performed on people anymore (at least not in the US, legally ??) but for a time were thought to be a great way to "reform" criminals. However, this surgery has some pretty serious side effects; in Intro Psych we watched a video featuring a woman without an amygdala, and she just was not entirely there. Emotion, including anger, rage, and fear, is normal and necessary. So what is it that makes it get out of control in people with "normal" frontal cortexes who seem to have all of the components necessary to behave in a way that our society finds reasonable? I think it is environment. Geoff says that he knows he will walk a straight line for the rest of his life. But, come on, can he really know that? I can think of situations where people are driven to kill, and I can also think of situations where people seriously believe that killing IS the right thing. Geoff also says that he knows the difference between right and wrong. But how? What if someone else also knows the difference between right and wrong, but knows something completely different from what Geoff knows? Who is right? We've evolved from animals who do not jail one another, who do not have the complex moral boundaries that we have created. Trust me, I'm not advocating going back to some primitive system without laws or limits. But can we really expect that in every conceivable situation these somewhat arbitrary moral boundaries will be accepted as "right"?
Also, so many people who are serial killers believe they are killing for some higher power, some force greater than themselves. I don't believe in God, but I can imagine that if I did, and I thought that the creator of everything in the universe wanted me to kill some people, I might do it. Religious devotion or faith can make people do extreme things. Usually these things fall into our society's boundaries of what is acceptable, which is why we can say that we let everyone practice their own religion. Well, belief in something intangible is something pretty hard to argue against. So if someone really, truly, wholeheartedly believes that God wants them to kill a few people, what do we do with them? Are they crazy? Are they right? They certainly think, as Geoff does, that they know the difference between right and wrong. But if they do what they think is right, they will end up in jail. What is it in our brains that defines right and wrong for us? Is there some universal human moral code ingrained into our brains (or at least those of us who are "normal") that says killing other people is wrong? Or have we completely invented this idea? Or is it just a feature of some tit-for-a-tat altruistic principle?
Sorry to write so much, but it's much more interesting to ponder human nature than to do my Spanish workbook exercises.
Name:  Sarah
Username:  sfeidt@brynmawr.edu
Subject:  Wow.
Date:  2003-02-09 22:15:45
Message Id:  4499
Comments:
Does anyone else feel overwhelmed?
If every single behavior is determined by the pattern of synapse activity in a given brain, it's mind-blowing to try to comprehend the complexity of it all. Imagine a piano, with 10^12 keys. Can you begin to fathom the number of different pieces of music that piano is capable of making? And now imagine that there are billions of pianos, and every one of them has the keys arranged differently. The same piece of music will be different on each piano.
The unfathomable variety of human behavior seems only logical when you think that each nervous system, made up of the same notes (neurons) in different orders, is capable of completely unique behavior, perception, interpretation...
Why is it difficult to believe that serial killers are neurologically different from everyone else? All it takes is that particular combination of keys/neuronal pathways, that particular 'song'/pattern of synapse stimulation to create a unique behavior, a song radically different from ours.
Name:  Katherine L
Username:  klafranc@brynmawr.edu
Subject:  emergence, also
Date:  2003-02-09 22:29:44
Message Id:  4500
Comments:
The 'emergent properties' comment from Andy reminded me of the grid of dots from the first week, where a simple set of rules could lead to an unexpected and organized outcome. In the grid, patterns were shown to emerge from randomness, without the need for a single creator of those patterns. It seems plausible that models based upon this idea could be applied to consciousness and the brain's role in it.
Name:  Luz Martinez
Username:  lmartine@brynmawr.edu
Subject:  
Date:  2003-02-09 23:15:31
Message Id:  4502
Comments:
I agree with Sarah. I am overwhelmed by the pieces that make up the nervous system and the way that neurons can have different arrangements that produce unique behavior. I am also very taken back by the ability of the nervous systems to interact with its environment even when there is a problem with the communication within the nervous system like in the case of Christopher Reeves.
Name:  Annabella Rutigliano
Username:  arutigli@bmc.edu
Subject:  Inspired by Defining the Self
Date:  2003-02-09 23:56:46
Message Id:  4503
Comments:
Katherine makes an interesting remark in her comments, stating: It is very interesting –Reeve reports, "I cannot move my foot" – but his foot does move—So what then is this mysterious "I"?

This "I" can be indicative of many different effects. Katherine attributes this "I" to be part of the definition of self. My question is what is this self. Is it the part of us that dreams, hopes, and aspires? Or is it simply neural pathways connecting the brain and spinal cord? Is this "I" indicative of the human soul?

Many define the soul as the thing that separates a single person from mass of others. Psychologists say that we only gain a sense of individuality when we reach a certain maturity of consciousness. Is this true?

Any maternity ward nurse could argue this statement. Looking at newly born infants some are fussy, others are more serious, and those whom are content. The variety is endless. What do these varieties hint at? It would be very simple to write them off as genetically structured differences. But in Reeves case, when the body is functioning properly—what does this say about the intangible mind?
Name:  Marissa Litman
Username:  mlitman@brynmawr.edu
Subject:  the overbearing brain
Date:  2003-02-10 00:31:50
Message Id:  4504
Comments:
I thought that Sarah's mention of the overwhelming complexity of the nervous systems and its many functions and capabilities was very much a feeling that was familair. I find it difficult to sort through my own brain and its basic activity, let alone recognizing the processes behind its functions and actions. In the first week of class I was still trying to come to terms with thinking about the brain as its thoughts, but now adding on its process has taken up another realm of possibilities that just makes things more complex, and makes my "mind??" work harder.

I thought that Sarah made a good point about serial killers. If there are so many parts to the process, than I do not doubt that one or several of the nuerons may be a little off. There are so many complexities that any sort of damage or alteration, either caused by physical impairments or ones that have developed through the thought process seem completely likely to me. That is, of course somewhat frightening as well to classify a human being as having an inclination to kill and it being innately physical, but is it not also possible that the brain can develop "wrinkles" that combat such behaviors over time as well?


Name:  Melissa
Username:  mosorio@brynmawr.edu
Subject:  Christopher Reeves
Date:  2003-02-10 00:33:13
Message Id:  4505
Comments:
Since the last class I have had the same question in my mind about Christopher Reeves. What if his foot was above a fire would he react to the heat? I don't think he would. It seems to me that the pinching is a given input relates to a specific muscle in his foot that reacts almost like a reflex.

I understand that if he doesn't pull his foot away when asked because his brain does not have anyway to give that signal to his spinal cord- since they were detached. The fact that he can't feel it may be attributed to the fact that the brain deals with feelings not the spinal cord.

But all of this makes me think that maybe the spinal cord can work on its own to produce certain behavior and maybe that is why Reeves can move his foot. Maybe the spinal cord reacts to its own inputs with specific outputs. All of this leads me to believe that there is something missing in our model of the nervous system- though I'm unsure exactly what that is.


Name:  Alanna
Username:  ajalbano@brynmawr.edu
Subject:  
Date:  2003-02-10 09:48:40
Message Id:  4507
Comments:
The question posed about Christopher Reeves on Thursday has me a bit stumped, but I'll try to make an educated guess. If you pinch his toe, and ask him if it hurts, and he says no, that makes sense b/c only the brain can tell the body if it is feeling pain or not -- and Mr. Reeves' brain is disconnected from his spinal cord. He also says that he cannot move his foot. This is because auditory processes (such as asking him to move his foot) are controlled by the brain, but the brain cannot pass this message along to the rest of the body. What I find interesting about these observations is that the nervous system is still able to find a way to function despite the disconnection btwn the brain and spinal cord. It is like each part of the nervous system has its own little department, and each of these various departments are connected in some way, so that a message is sent from one part of the body to the other. If one of those connections is cutoff or disrupted in some way from dept. to the others, then each department continues to work within itself and with the other departments it is still connected to. The disconnection just means that the message won't get all the way through. That is why Mr. Reeves' body doesn't function as it should. The nervous system appears to have its own backup system so that it may function as much as it is able, even when something goes amiss.
Name:  Kelvey
Username:  krichard@brynmawr.edu
Subject:  'Natural' Movements
Date:  2003-02-10 09:56:53
Message Id:  4508
Comments:
My thoughts have been similar to Melissa in terms of what happens when a quadrapalegic puts their hand on a hot wire and when it starts burning them, will they pull their hand away? If so, by how much? What is the instinctal/natural movement? For Christopher Reeve, when his toe is pinched, his toe moves away without his brain telling bim to move or him even being concious of the fact that there was pain or movement. The natural movement of the foot is to pull back. Now in the case of the hand, the 'natural movement', being defined as the closed circuit from the muscles in the hand to the spinal cord without the direction/input from the brain, may be to curl the hand, and if it is a small object the person will simply hold the wire tighter. For example, without being paralyzed, a person may grab an electic wire after being shocked by it. It seems thatlike Christoper Reeves toe movements, to close the hand is natural and is confined within the closed circuit of hand and spinal cord and therefore the response is made before the brain can influence the reaction and rationalize against instinct.
Name:  Grace Shin
Username:  gshin@brynmawr.edu
Subject:  stumped?
Date:  2003-02-10 10:13:00
Message Id:  4509
Comments:
I think the C. Reeves situation is quite interesting. I actually never knew that if you pinched the toes, that there actually is a reaction. This actually makes me think that the boxes in boxes in box model is quite true. However, to redefine the limits of the final outside box. So, before we said that the big box was the nervous system, which included the brain and the spinal cord. However, it seems that the two, brain and spinal cord, needs to be in separate boxes. Because in this case, even when there is one input to one of the two, mis-wiring could result in this situation with C. Reeves.

So, maybe the big box is not the central nervous system but something bigger which contains the two... which would mean brain does not equal behavior. But i feel like i need to be continually listening and reading to really validate my idea.


Name:  viv
Username:  vbishay@brynmawr.edu
Subject:  
Date:  2003-02-10 13:55:50
Message Id:  4510
Comments:
This is pretty off the topic being discussed in the forum right now but I'd just like to contrast the approach to brain=body we've taken in class, which is based on western views and understanding to that of a different culture. Many east-asian cultures are deeply rooted in various forms of holistic training. Holistic practices such as yoga and tai-chi are based on the connection between mind and body and focus on strengthening and centering the mind through training of the body. As I see it then, such cultures have had a deep understanding of Dickinson's concept of brain=body for quite some time now. One particular form of training that I am more familiar with is the art of Gi Gong, a korean form of yoga. According to the holistic practice behavior must be restricted to strengthen the mind- not only in the sense that you should abstain from drug and alcohol use but every part of your body should be kept in prime condition to optimize the workings of the brain. The key to many such forms of training is a focus on strengthening the abdomen, which is considered the energy center of the body. This brings me to the concept of the enteric nervous system, the 'other' nervous system that resides in our gut. Maybe it deserves more attention than we paid it in class. With a population of 100 million nerves that transmit and process messages, the enteric system seems to me equally complex or at least significant as the spinal cord. The fact that the CNS and enteric systems both originate from the neural crest during fetal development tells me that it shouldn't be discounted as a lesser part of our nervous system. And since many asian cultures seem to me to have a heads up that spans centuries on understanding the connection between the brain and the body maybe a closer look at the enteric system wouldn't be a bad idea.
Name:  maria
Username:  mcruz@brynmawr.edu
Subject:  memory vs. reality
Date:  2003-02-10 14:44:05
Message Id:  4511
Comments:
This comment might not be immediately related to what we have been discussing in class, but I was reading over the postings, and someone mentioned how supposed predictions of events fit in with the question of whether or not brain=behavior. That led me to wonder about moments of deja vu, those times we see something and are certain we have seen this exact thing before. How are such impressions created? What is it that tells us that we have experienced some event before when that is not realistically possible? I have also been wondering about memories. Where on a neuron is information stored? Do specific neurons hold specific information, or do we have a sum of knowledge in our brain that is just in constant motion? Perhaps false memories are created by improperly connectioning of certain pieces of that information to create something novel which we are convinced actually ttok place. Any thoughts?
Name:  Nupur
Username:  nchaudhu@brynmawr.edu
Subject:  Coffee Comment
Date:  2003-02-10 16:55:59
Message Id:  4513
Comments:
Biz, I thought it was interesting that you served decaf with out telling people, and that not many noticed. However, I am not surprized. To a certain extent, I believe that there are times that we are told things, or do things that make us feel better or feel differently, had we known the truth. The coffee example is one, anotther, is the use of medication. I'm not talking about heavy medication, but the use of tylenol or advil...I do think that there are times that the act of taking a pill makes more of a difference than the pill itself. I have friends that dont like taking pills or medicine and do just fine, and yet the moment I think a headache is coming on, I take two tylenols for good measure. I know that this is wrong, but I think that I have made myself believe that with out pills, my headache will not go away. Had I not taken those pills, I know I would have my headache for much longer.
Name:  Arun
Username:  asingh@haverford.edu
Subject:  10% Myth
Date:  2003-02-10 19:19:14
Message Id:  4515
Comments:
This is obviously off the topic, but I just thought I'd post this up because I was curious as to how the myth "That we use only 10% of our brains" started after hearing one of our colleagues ask that question in class. I found from a website that the 10% statement may have started from any one, or combination of these observations and comments. A misquote of Albert Einstein or the misinterpretation of the work of Pierre Flourens in the 1800s. It may have been William James who wrote in 1908: "We are making use of only a small part of our possible mental and physical resources" (from The Energies of Men, p. 12). Perhaps it was the work of Karl Lashley in the 1920's and 1930's that started it. Lashley removed large areas of the cerebral cortex in rats and found that these animals could still relearn specific tasks. And like all myths, after popular media kept repeating the false statement, soon, everyone began believing the statement regardless of the evidence
If any of you want to learn more about this myth or other REALLY interesting facts about neurobiology, I suggest you check this site out. It is directed towards kids, but by simplifying things, you can grasp the ideas a little better. http://faculty.washington.edu/chudler/tenper.html
ENJOY!!
Name:  Sarah
Username:  sfeidt@brynmawr.edu
Subject:  So beautiful.
Date:  2003-02-10 19:47:46
Message Id:  4517
Comments:
Neuroscience Art Gallery
Name:  Neela Thirugnanam
Username:  nthirugn@brynmawr.edu
Subject:  
Date:  2003-02-10 20:56:29
Message Id:  4521
Comments:
I was intrigued by Katherine's, Andy's, and Annabella's discussion of the placement of "I" within (or outside of) the brain and behavior. In normative thought, we tend to separate the body (NS) from certain behaviors. Instinct (unlearned, untaught, and perhaps unconscious behavior) is made distinct from the behavior of free will (the conscious "I"). The human conception of "self" seems to stem from our unlocated consciousness. However, if we conceed that brain= all behavior, then the sense of self should be located in the nervous system along with our other more innate behaviors. Perhaps self is controlled by an emergent biological aggregate, or perhaps it is controlled by an experience - more of a psychoanalytical moment.
Playing the devil's advocate, maybe Annabella's example of newborns' differing personalities isn't really a display of a child's expression of "I" (or soul). Maybe they are merely behaving unconsciously out of instinct located within the nervous system. Freud claims that subjectivity and consciousness emerge from a temporal and environmental occurance a bit later and it not a direct result of natural biological right (but Freud seems to have had plenty of his share of wrongs).
Name:  Shanti
Username:  smikkili@brynmawr.edu
Subject:  
Date:  2003-02-10 22:31:45
Message Id:  4522
Comments:
After looking at some of the postings on the forumn, I am getting the impression that people are uncomfortable with the idea that maybe our brains aren't that much different than a serial killer's brain. We resist that idea in the same way that we resist the notion that no free will exists. We'd like to think that as moral and rational beings that we are capable of choosing our own destinies and that we are aware of what is right and wrong. But are we? How different are our brains from serial killers? I agree with what Clare said that maybe what is different about a killer's brain is what makes him an individual rather than being what makes him a killer. I think that we feel that our brains' must be different because if they weren't than what prevents us from being serial killers too? Similarly, I think that we feel that we must have free will because that is essentially what separates us from animals, along with the more complex thought processes which go along with free will. But how different are we really from animals. Aren't humans just another, higher form of an animal? There is a very small difference between a human's DNA and an animals, but we try so hard to look at the differences that we don't see the similarities. It is true that people's brains are different, but in many ways we act the same. I feel like the question we should be addressing is that how is that we are capable of such varied behaviors when so much of our brain is the same? Can one subtle difference make us such completely different people? Or is it that while we are all different, we are not as different as we would like to believe. Would it bother people to think that maybe we're not quite as different as we think we are?
Name:  madeleine
Username:  madeleinedelson@yahoo.com
Subject:  conjoined twins
Date:  2003-02-10 23:11:16
Message Id:  4523
Comments:
A feature on the Discovery Channel about conjoined twins forced me to reconsider the idea of brain=behavior. The show journies into the lives of several conjoined twins, of which one pair, Lori and Reba, are cariopagus (skulls conjoined, two bains fused). Although the girls share a common prefrontal cortex, the anterior portion of the fronal lobe that has is very important for the determination of personality and other higher cognitive function, they are unique individuals. Reba, who also suffers from spina bifida, is more assertive and aspires to be a country singer; Lori is hoping to get married and have children. If the girls have only one prefrontal cortex, how is it that their personalities, emotions, and bahviors are different?
Name:  
Username:  Anonymous
Subject:  oops
Date:  2003-02-10 23:12:38
Message Id:  4524
Comments:
I meant craniopagus. Oops.
Name:  Alexandra Lippman
Username:  alippman@brynmawr.edu
Subject:  consciousness and unconsciousness
Date:  2003-02-10 23:54:29
Message Id:  4526
Comments:
I wanted to discuss something different from what other people have written about. Hopefully we'll be able to cover what I'm writing about later. I was wondering what other people thought about the "cusp of consciousness."
Today I had an Inca archaeology class at U Penn, and I kept nodding off during the slides because I was very tired. In the middle of my notes about pre-Inca civilization I wrote about swimming. I just finished my swim season, so I guess it is still on my mind. I had no idea, however, that I was thinking about it at that point. Also can the word "thinking" be used to describe something that is unconscious? What could that mental process which generated the word "swim" in the middle of my class notes be called?
Writing while very tired or while falling asleep has led me before to write about topics which I had no idea I was "thinking" about. I guess the existence of outputs such as unconscious writing would necessitate inputs. These inputs, however, can be very hidden, and it seems like their hidden-ness would be an example of the extreme complexity and often concealed nature of inputs. In addition to the idea of the secretiveness of inputs, the idea of a boundary between consciousness and unconsciousness interests me. Because of behavior such as my note-taking being able to define the divide between awareness and unconsciousness seems problematic.
Name:  Christine Kaminski
Username:  ckaminsk@brynmawr.edu
Subject:  Christopher Reeves
Date:  2003-02-10 23:56:52
Message Id:  4527
Comments:
As I was looking into Christopher Reeves' condition online, I stumbled into a page assessing the benefits to cloning. Among others like human stem cells that can help repair the body and conditions like cystic fibrosis and liver/kidney failure, cloning can works wonders on spinal cord injury.

According to the site: http://www.geocities.com/vgpuk/cloning.html
"We may learn to grow nerves or the spinal cord back again when they are injured. Quadriplegics might be able to get out of their wheelchairs and walk again. Christopher Reeves, the man who played Superman, might be able to walk again."

Looking into other sites, I've seen that people believe that they are spared their own life, like we have seen with Reeves, because of the power of their mind. So many of his abilities were taken away in an instant. Faced with the desperate nature of his circumstances, he no doubt questioned why and whether or not life was worth fighting for. Incredibly, he saw that those significant people close to him needed him and he chose to live.

So right now it seems that we're at somewhat of a standstill-there is much interest and foreseen benefit in cloning to aid the human body, yet so much controversy remains. As of now, the lucky ones who have the strive may just be the ones who will survive such a tragedy. Maybe it's their mind that saves them.


Name:  Kat
Username:  kmccormi@brynmawr.edu
Subject:  
Date:  2003-02-11 00:19:35
Message Id:  4528
Comments:
I come from a family FULL of dorks. Because of this, we often sit around the dinner table discussing the difference in varying people's behavior- mostly because my dad deludes himself into thinking that people my age are subject to a generational illness which causes laziness and complete lack of ambition. In our discussions, the nature vs. nurture debate is a frequent subject. Almost no one believes it is either one or the other anymore; rather, most people believe it is a mixture of both. My brother likes things black and white and so he confines this mixture to a percentage: say 60% nurture and 40% nature. I disagree with his analysis ( read: simplification) of the basis of human behavior vehemently- rather than the "mixture" he believes, I envision the factors that influence behavior in overlay, and the factors are not merely limited to "nature" and "nurture", but include structure and function of the brian, free will, and many other factors that have entered into our class dicusssions. It's gratifying for me to hear Sarah's analogy of pianos that introduces infinite variation and complication, yet at the same time, I realize that trying to understand and talk about something that is so complicated can sometime seem futile and obselete. Is the model of the brain that we have been evolving in class getting us anywhere nearer to being able to talk about behavior in a way that is not an oversiplification and yet is still manageable?
Name:  Alexandra Lippman
Username:  alippman@brynmawr.edu
Subject:  consciousness and unconsciousness
Date:  2003-02-11 00:23:55
Message Id:  4529
Comments:
I wanted to discuss something different from what other people have written about. Hopefully we'll be able to cover what I'm writing about later. I was wondering what other people thought about the "cusp of consciousness."
Today I had an Inca archaeology class at U Penn, and I kept nodding off during the slides because I was very tired. In the middle of my notes about pre-Inca civilization I wrote about swimming. I just finished my swim season, so I guess it is still on my mind. I had no idea, however, that I was thinking about it at that point. Also can the word "thinking" be used to describe something that is unconscious? What could that mental process which generated the word "swim" in the middle of my class notes be called?
Writing while very tired or while falling asleep has led me before to write about topics which I had no idea I was "thinking" about. I guess the existence of outputs such as unconscious writing would necessitate inputs. These inputs, however, can be very hidden, and it seems like their hidden-ness would be an example of the extreme complexity and often concealed nature of inputs. In addition to the idea of the secretiveness of inputs, the idea of a boundary between consciousness and unconsciousness interests me. Because of behavior such as my note-taking being able to define the divide between awareness and unconsciousness seems problematic.
Name:  Enor Wagner
Username:  enorenor6@aol.com
Subject:  serial killers
Date:  2003-02-11 00:35:38
Message Id:  4530
Comments:
Our class discussion on Tuesday enticed me to do some research on serial killers. It was alleged in class that the frontal lobes of serial killers are typically damaged or appear to be different than those of less/non violent people. I researched serial killers online and read through a million web pages but still came up short of any statistical information with regards to the damaged frontal lobe common among serial killers. However, thinking along the lines of brain = behavior, I would like to assert that there is definitely a correlation between the damaged frontal lobe and serial killers. Don't get me wrong, there are a lot of exceptions, I'm sure. Although, as Cordelia has said, the frontal lobe plays an enormous role in suppressing a person's aggression (I believe it is important to keep the monkey experiment in mind). When the frontal lobe is damaged, it has been proven that a person will act with more aggression, and less judgment. What I think is important to point out though is that serial killers who have damaged frontal lobes are not typically born that way – in the majority of cases, head trauma has been directly related to their less than adequate minds. According to a number of sources, that head trauma was often the result of physical (most of the time parental) abuse.
Other behaviors have been found typical in the childhoods of serial killers as well. Psychologists refer to the early warning signs and commonalities among serial killers as the 'dangerous triad'. The triad consists of three tell tale signs of a disturbed child – bed wetting, fascination with fire (arson), and animal abuse. Although not every child who can be categorized as practicing the characteristics of the triad becomes a serial killer, is it merely a coincidence that most serial killers fit this childhood description? Scientists and Psychologists have thought that the triad (each part) is representative of a greater danger. Bed wetting typically signifies a poorly raised child who suffers from either neglect or abuse, and can also be associated with the lack of self control. Arson implies an either sexual or aggressive need. Fire is used by angry children who need release. As for animal torture, psychologists have thought that the urge to torture and kill feeds a young mind which is sadistic and merciless. The questions in my mind are – is this triad merely the signs of a problem child who may or may not grow up to be a serial killer? If not all serial killers suffer from a damaged frontal lobe, then what accounts for the behavior of those who do not? And, is it only problem children who grow up to be serial killers? I believe that the environment affects the brain (literally, in some cases, and figuratively in others) and that changed brain is responsible for behavior, which encompasses all consciousness, beliefs, judgments, and thought process.
Name:  Zunera
Username:  Anonymous
Subject:  Mistake
Date:  2003-02-11 00:47:42
Message Id:  4531
Comments:
wow. i was just reading over my last comment (in the last forum) and i realized i made NO sense whatsoever. in any case, i retract the statement that the brain of the wolf children/wolf boy are not different from "normal" brains in structure.

as discussed a gajillion times in class, if brain-behavior then all brains must be somewhat different (structurally), because no two people are exactly alike, even identical twins.


Name:  Adina
Username:  acazaban@brynmawr.edu
Subject:  
Date:  2003-02-11 02:44:31
Message Id:  4534
Comments:
As Elizabeth said in her message people who do not know that they are drinking decaf coffee will not realize the difference between their usual regular coffee and the decaf that they are now drinking. This is very similar to the examples of people feeling "high" because they think they've taken an illicit drug, when really they've only taken an aspirin. Also, many times when a person is depressed or stressed, he or she will feel nauseated. And let's not forget hypochondriacs... they imagine that something is wrong with them and their bodies respond by actually developing a feeling of sickness. These psycho-somatic examples seem to imply that the brain has a great power over the body, perhaps even greater than even external stimulus. However, this seems to makes sense when using our description of the brain, because isn't external stimulus received by receptors that carry the stimulus to the brain? It would seem reasonable then that the brain would be able to alter its interpretation of the stimulus. This, however, is still a magnificent feat and I am constantly amazed at its awesome power. The apparent fact that the mind (using mind and brain interchangeably here) can control what the body experiences and can even trick itself boggles my mind, and I wish that there was much more knowledge about the brain than there is today.
Name:  Erin Fulchiero
Username:  zegrete@aol.com
Subject:  brain plasticity and repair
Date:  2003-02-11 02:47:08
Message Id:  4535
Comments:
I recently read a study, which claimed that Christopher Reeve's brain has remained receptive to signals from the paralyzed portion of the body, even though the majority of those signals were interrupted by his injury. This particular study noted that several animal studies suggest that repairing the spinal cord would have little benefit for injuries such as Reeve's because the brain effectively "gives up" on the paralyzed portions of the body and is altered so that it no longer is able to process those signals. In that I remain only marginally aware of the capabilities and mechanisms of the brain's functionality, I am curious to understand what sort of reorganization process that system can potentially utilize in response to trauma.
In a study conducted by Dr. Maurizio Corbetta, a neurology researcher at Washington University, an MRI was used to map the patterns of brain activity in response to touch and movement. In this study, Reeve followed the video image of a tennis ball and indicated its direction with either his tongue or the movement of the left index finger. Throughout this activity, the MRI detected the active parts of the brain and monitored its responses to specific actions and sensations. The results of the MRI were then compared to identical tests conducted on a healthy young man. The results would have seemed baffling to me only weeks ago: only slight differences were recorded. Reeve's brain was apparently quite normal as it indicated by the sensory maps of the MRI. It was found that he had feeling in both his foot and hand. Apparently, the areas of the brain which normally control the hand had been taken over, to some extent, by those areas which control the face. However, the brain circuits linked to the foot were normal. A new awareness of the plasticity of the human brain and the extraordinary capability of the human nervous system to "evolve" behaviorally through a solely biological process has left me questioning what possible distinction could remain between brain and behavior.




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