Biology 202 Neurobiology and Behavior Spring 2001

How useful are concepts like "central pattern generation", "corollary discharge", "proprioception and reafference", "genetic and environmental influences" in making sense of "action"? in what ways might one use these ideas as well to better understand other aspects of nervous system organization/behavior?

"During stage 1, which is light sleep, we drift in and out of sleep and can be awakened easily...People awakened from stage 1 sleep often remember fragmented visual images. Many also experience sudden muscle contractions called hypnic myoclonia, often preceded by a sensation of starting to fall. These sudden movements are similar to the "jump" we make when startled."

Brain Basics:Understanding Sleep http://www.ninds.nih.gov/health_and_medical/pubs/understanding_sleep_brain_basic_.htm

• action as a "motor symphony"
• proprioception and reafference
• central pattern generation
• genetic and environmental influences
• distributed control
• corollary discharge = efference copy
• influences of corollary discharge on "perception"
• corollary discharge as creating "expectations" for input

Given the complexity of the nervous system, it is impressive that so little goes wrong, generally speaking. The wide variety of topics covered in the web papers from last week may reflect, in part, some of the ways in which the nervous system is capable of malfunctioning. I find the ways in which the different parts of the nervous system work together to achieve one end to be much more interesting than the ways in which each separate unit functions independently. To me, one of the most striking things about the nervous system is that it seems so arbitrary and yet so coordinated. What, evolutionarily speaking, motivated it to become organized in the way that it did? It may be that the only way to understand the whole of the nervous system, both its inputs and its outputs, may be to examine each smaller "box" such that the bigger "box" might be accurately constructed, with deference towards a possible biggest "box," made up of both nervous system activity and contextual influence, that may as of yet escape definition

Like…Incubus!

Has anyone ever heard of this creepy character? Well, while I'm still trying to decipher an experience I had approx. two and a half weeks ago. I have not thought much about it until today, while browsing through past web papers. I came across a paper about sleep paralysis and awareness of sleep paralysis (ASP). I was happy to find an explanation for this experience that I have way, way to often (at least 1 a week or once every two weeks)!!! It involves being in a normal paralyzed state during REM sleep, but then awaking to conciousness and being unable to move any part of your body. The information that I have read on this says that people can only move their eyes. My experience is that I can barely move my eyes (they just flutter a lot in my attempt to wake myself up) I also experience a burning in my chest as a result of trying to wake up. It kind of feels like I'm doing some damage to myself, but I do pretty often and when I wake up I don't feel any different, so I'm probably not doing to much damage. I can also lift my head a little bit. It's pretty bad because the experience reminds me of an infant just learning to lift its head. The experience is pretty stressful, so sometimes I just let myself fall back asleep and say I'll wake up whenever. Usually, I am trying to wake myself up from a bad dream or a nap. Anyway, recently I had the experience during an ASP session that somebody was there in the room with me…on my bed. I could feel this person's breath and they were trying to kiss me! It was a horrible experience because I thought somebody was there, well I knew nobody could have been there because it wasn't a dream, and I just could believe that there could be another being in the room with me. I vaguely remember them saying something, but all I could feel was there breath and their presence. I forced myself to wake up by trying to open my eyes and move my head, and after who knows how long I woke up and noticed that there wasn't anything next to me, except of course my E.T. doll. I gave the doll a strange look, and felt a burning in my chest, from trying to wake myself up. Needless to say I took some time before going back to sleep. Upon reading this ASP paper, I read that this is an experience that occurs almost 30% of the time to ASP experiencers, not only that, but there is a name for my particular experience:

Incubus/Succubus: An Incubus is a spirit/demon that seeks sex with sleeping females while a Succubus is a spirit/demon that seeks sex with sleeping males.

How horrible that this is a well-known (it is described by scientists and others interested in dreaming and sleep)!!!

Fortunately that was my only experience like that…with "incubus." A time when my brain seemed to create more than my behavior!!

Just thought i'd share that with you all :o)

I guess it also depends on your interpretation of reality. Corollary discharge signals support the idea that reality is just the way in which the brain interprets input. But this view implies that there are different realities for every person, because everyone has a unique brain. But if you believe that there is one reality shared by all, corollary discharge signals are difficult to make sense of, as seen when we discussed phantom limbs. The reality of the person with the phantom limb is that there is pain in the region where the physical arm used to be. But the reality of others is that there is no arm and therefore there are no sensory receptors to interpret that pain and provide verification of the location of the arm. This returns me back to the issue of having receptors specific to a sensory input, differing humans and some animals in which they have certain recpetors for such inputs while humans may not. So what is reality?

I think that corollary discharge is a good way to explain why we all percieve things so differently, but what triggers the discharge and why do we need such an internal control? Why isn't the external input we recieve enough for us to know what is going on around us?

I guess I still have so many questions that I hope we can answer...

To make the educated guessed they do, profilers have studied numerous other cases and found similarities between them. But to be able to guess the make and color of their quarry’s car seems impossible, almost like a magic trick. Sometimes I think there is less individuality in individuals than we were lead to believe. Our ‘unique’ likes and dislikes sometimes aren’t spontaneous; they’re the result of inputs that other people react in similar ways to. Yet, then again, there is proof of the opposite. Study of serial killers show that they are often the result of abusive families. But why do some abused children grow up to be humanitarians while others grow up to be Ted Bundy? I suppose that until we can find more information on ourselves and how our perception works, a lot of our behavior will have to be attributed to the mixed bag that is the I-box. Still, each person is not as different from the other as we think.

Dealing with the annoyance and misery of having bronchitis for the last week and a half has made me start thinking about how we deal with stimuli, including illness. How often do you hear the phrase 'mind over matter'? Now this often refers to some physical obstacle that we face in the outside world. But isn't the brain and the biological processes that take place there 'matter'? The majority of discussion presented thus far has focused on this very problem: equating physicallity with abstract things, like self or behavior. Is 'mind over matter' really 'matter over matter'? If self is linked to the brain then it's biology's fault we can't accomplish everything we want to do.

So, could I have recovered from my illness without taking antibiotics, and instead willing myself to feel better? Would the brain biologically compensate for the desired behavior of health? There is something to the psychosomatic nature of illness, and even hypochondria. When we feel sick it is sometimes a state of mind. And it's possible that this state of mind is a physical state. Maybe. Regardless of the answer, I find the idea interesting.

Thinking about the same sort of CPG, is talking a learned experience or will everyone talk eventually. It seems to me that is must be learned because languages are different, and little kids are must more receptive to learning new languages. This must be because there are certain areas in the brain which have the potential to be patterned at a young age, but as we get older the brain and nervous system are less receptive to changes in behavior. I wonder about this, because I have a 2 and 1/2 year old nephyw who still isn't talking. There are a few words he can say, but mostly he just babbles. Unlike most little kids, when I try to encourage him to sound out words, he refuses. He seems not to want to learn how to talk. I wonder if it has to do with him being the second born and getting what he wants without clearly asking for it. I try to tell him that the only way he will get anything, is if he asks for it in English. He understands everything I say, it seems, but he is reluctant to learn more.

This intrigues me because it might mean that the connection between the CPG and the brain and nervous system occur at different times during the life cycle.

Like your intuition that it is a "gene symphony" rather than a gene. And yes, genetics contributes to lots of things in addition to (some) central pattern generators. To talk about more as the course goes on. In the meanwhile, have a look at http://serendipstudio.org/gen_beh.
PG

On a different note, I find the whole concept of central pattern generation very fascinating. The nervous system stores so much information and is able to access all of it at incredible speeds. I think this aids in explaining how computers work. Each store information and utilize it in various processes. If a computer were to have as many interconnections as the nervous system would it become self-aware? I have always wondered about this because of some books I have read. In one called The Moon is a Harsh Mistress as more ports and functions are given to the computer it becomes conscious. I think this would be a very valuable experiment to try because it could offer insight into how we ourselves become self-aware.

Those are all of the thoughts floating around in my head for now. I'm sure more will come tomorrow after class.

In fact, this makes me wonder what the whole nervous system is for. I had always assumed that its main goal was gathering information about our environment, but if our glimmer of reality is affected by proprioceptive information, efferent copies, prior experience, and even transient mood changes, then it seems that the nervous system isn't necessarily doing a great job of keeping us in touch with the outside world. It's more as though the nervous system is keeping us in touch with ourselves, "ourselves" including as a very small part our position in and relation to the outside world. But the nervous system doesn't seem at all concerned with accuracy in representing reality; it only has to do a good enough job to make sure we don't get killed, we can find food, and we can recognize a mate. In some ways, this is a little discouraging...but then, that's just my perception of it at the moment.

To touch briefly on Claire's question about learning language, I can share that it seems that children do in fact learn just about anything better because the composition of some key neuronal receptors is different. I could try to explain what I remember, but it's probably better to just provide a link to the article I read, which is accessible through Serendip's collection of Scientific American articles. The article, Building a Brainier Mouse, is written by Joe Tsien, the Princeton University researcher who created a strain of "smart mice."

And finally, since I'm having a lot of fun since I learned how to create links: neuroscience hits the funny pages - a look at sensory perception a la Rose is Rose.

This issue of storage brings into question what exactly the nervous system is for. Like Daniel, it's purpose as indicated by what we understand of its function seems to contradict how I know it from living with it for 18 years. It seems as though it is kind of a vending machine-- you put something in, you get something out and occasionally it randomly gives you free things. But what about that all too familiar use of the brain as a big box of knowledge and fact, none of which directly results in behavior?

These statements caught my attention: "How do we know what's what?"--Kate; "Our 'unique' likes and dislikes sometimes aren't spontaneous; they're the result of inputs that other people react in similar ways to."--Dena; "When we feel sick it is sometimes a state of mind."--Alexis.

In addition, the ecstasy article stated that "look-alike" or fake ecstasy pills are being taken; however, people claim to be experiencing the same effects without even knowing that the pills are not the "real stuff." Can a placebo cause the same effects as the actual substance? Or maybe because society claims certain results, we react unknowingly in favor for these inputs... Or maybe it is a state of mind; maybe it's not the drug, but the thought of what the drug can do that enables certain behaviors to occur... Just wanted to share some thoughts with y'all.

And the fact remains that there indeed are many different but equally correct ways of looking at things. Many different people, for instance, may agree upon the nature of an object they are all viewing but may deem different characteristics of the same focal point as most attention-grabbing. Just like this forum. Many of us choose to write about the same topic, but take different perspectives and mix the common concept around with different "corollary discharges" to express our own unique coordination of internal signals, or give it our own original twist.

In additon, maybe corollary discharge is a possible "something else that is narrower [than free will], yet still accounts for the variety of human behavior found in all people" that Matt talked about. The concept of corollary discharge is still a little fuzzy to me when we move beyond swimerettes, but it does appear to play a crucial role in the enormous task of juggling our many different inputs and awarenesses in a way that integrates our "selves," internal environments, and external environments into a coherent experience.

The idea of corollary discharge makes this concept of a symphony even more interesting because neurons directly influence one and another. It makes sense that neurons coordinate with each other to synchronize basic motor activity, but I do not think I ever considered that individual neurons communicate with each other, without a separate conductor . . . that the lines in the box can really go in any direction--including side-to-side and backwards. The central pattern generators which cause the motor neurons to send out signals to adjacent ganglia along with output signals are created through learning and genetically-determined circuitry.

Genetics, though, determines the basic circuitry of most CPGs. Thus, we see that our inputs and behavior are in a large part due to internal factors which determine how we interpret and share signals. Though we may all exist in a similar environment, our reactions to it vary greatly because of the minor differences among us which determine our neuronal circuitry. I came across the same idea in class and in my webpaper, that no one can have the same experiences because everyone perceives it differently. In researching about synesthesia I learned that the hippocampus influences the sensory perception of all of us, by determining what input is significant over others. These ideas of perception certainly questions how objective we can be about perceiving reality. It would be interesting to see to what extent exactly our own genetics effects our perception of reality.

So maybe preprogrammed behaviors are those that are the first in a series of actions needed for a particular aspect survival. Or perhaps they are all locomotor skills seing as how the other example we discussed was flight in birds. I don't know. If anyone has any ideas, let me know.

The brains of birds are wired to learn the song of their species, but that song must be heard in order to actually learn it. For example, if a bird hears the song of its species in addition to the songs of other species, it will reject the other songs and learn that of its species. If a bird does not hear any song during its infancy (if kept in isolation), it will sing a "generic" song that is not as complex as that of a normal song. This demonstrates that there is a central pattern generator, but that this CPG can somehow be altered through experience (ie, hearing the song of one's species).

Another concept I found interesting is that of the "critical period" wherein the neuronal pathway of a song must be established within a certain time period in infancy. If a song is presented after the critical period, the bird has a very difficult time learning it. This has a correlate in humans in that it is more difficult for people to learn a second language after puberty. For some reason, neuronal pathways lose plasticity. (Why is this?) Perhaps there is some truth to the cliché "you can't teach an old dog new tricks."

There are many stories of abused children that have no form of language input but when found before puberty are able to learn language with little trouble. On the other hand there is a famous case of a girl who was found locked in an attic at the age of 12 and although she tried very hard to learn English she never was able to speak fluently. I believe that she never learned to use the correct syntax in her sentences.

So what is it that allows children to learn langauge at such a vast rate? Researchers say it is that children's brains have neural plasticity, that is the abilty to make connections and remove those that are not needed. Thus, a child who suffers a brain trauma in the left hemisphere where language is located for most people will be able to speak and understand again. However an adult with that same leison would not be able to recover as much langauge function. If you are interested in language and how it fits into the nervous system I suggest reading books by Steven Pinker. He is a cognitive scientist at MIT who has written books on this stuff that is meant for laymen. They are very readable and really explain how language is thought to work.

I believe that langauge is a form of central pattern generation. It is found that babies in their initial babbling stages (ie before age 6 months) bable in all phonemes of all languages of the world. However, as they recieve more input from thier caregivers who talk to them, they begin to babble in only the phonemes of their caregiver's language. So the human brain has the ability to learn any language. It is through the fine tuning of listening and copying the caregiver that a baby begins to learn the language that he/she is exposed to. Also, deaf children of parents that don't know sign langauge make up thier own language of gestures. While it is not as complex with all the syntax of something like ASL, it certainly has the rudements of langauge. One can clearly say that these children do not have any language input but they seem to make up language on their own. Also, recent research in Nicaragua has watched the development of a totally new langauge, Nicaraguan Sign Langauge. NSL is a new language about 20 years old. It is a result of the deaf community of Nicaragua coming together and putting all their own gestures into a codified language. It came out of this community wanting to communicate. All of these people had created their own gestures at home with the hearing population around them. When they finally came together as a community, they deaf people created a syntax and official signs over many years. So I think that there is something of a central pattern generation in language. I think it is one of the key central pattern generators.

Ok, I swear that is it for me this week.

Additionally, it is fascinating to consider a simple action as a complex motor symphony consisting of a wealth of complementary parts that fit together so perfectly. Phantom limbs are caused by misshaps that don't affect the circuitry inside the nervous system. What other instances cause misshaps in the interior workings of the nervous system?

What kind of actions are actually acquired? How large a part do the environment and experience play? It seems to me now that a large number of motor symphonies are always present and don't require any outside inputs. It seems like almost everything humans need is coded for in our unique genetic information.

I'm still very confused regarding phantom limbs though, although it is a fascinating topic. How can we still feel it has been due to the motor circuitry and corollary discharge signals that move the arm and makes one still feel the arm. Before we could have such knowledge, it would be amazing to see how doctors and other people would have reacted to people complaining of phantom limbs. The source of the corollary discharge signals, etc. though still eludes me, I feel we should have captured it in more detail during class. Nevertheless, the topic made me wonder how important the overall coordination of the body results from communication between boxes in the nervous system. I can see how this course is evolving into Grobstein's main belief that brain = behavior. Scary.

It has happened that former addicts who have been completely rehabilitated/detoxified go back to their old environment and suddenly begin to experience biological symptoms of withdrawal.

Tolerance occurs as a drug is taken often and the person must take higher and higher doses in order to get the same effects. A fact related to this that surprised me was that some drug overdoses occur as a result of a person taking a drug at a high dose which they have taken many times before (i.e. a dose which may their body has adjusted to), but this time in a different environment or situation than usual. In that environment, the drug actually causes an overdose, whereas in the usual context the drug would not have had that effect. This idea has also been supported by research. (I haven't gotten a chance to actually look up these studies just yet, but this is one example from class.) For example, in one study, animals were divided into two groups (A and B) in two different living spaces, and were given morphine for a certain period of time. Then, some animals were moved from the B area into the A area (so that a few animals were in a different context than they had usually received the drug). All of the animals were given a high dose of morphine (LD-50, a dose usually causing 50% of the animals to die). They found that significantly more of the formerly B animals died. Was it a result of being in a different context?

Although not all tolerance, withdrawal and relapse can be accounted for by conditioning, it is definitely an interesting area of research... and could have important implications for the treatment of addiction. It does seem to shed some light on (or maybe just complicate things) the amount of control/influence our minds have over our bodies...

It's not like we can look into the brain and choose a spot (where we don't even know what the function is) and decide how dopamine issues cause schizophrenia, or how seretonin issues cause OCD and Depression.

We were talking about how the seretonin issue in OCD is discovered and uncovered by finding the levels of seretonin metabolites in the spinal collumn, and how those change with drug treatment. We basically have to find the answers 5 or 6 degrees away from the actual answer. We have to assume (by probability) that these chemicals, that effect seretonin, since they're in different quantities in diagnosed individuals, might lead us to a seretonin based hypothesis. Though, where does it work? what exactly is the cause? There are only so many neurotransmitters (that we know of) and yet we can attribute them to multiple problems. And yet we barely have the knowledge to look at where they go and where they work. We have to keep moving closer and closer to the problem through details we notice that may be far away from the answer. This is extremely hard. I think I was a little daunted. But fascinated as well. These chemicals are incredible. We barely have the means to understand them. And if drugs that effect them effect these disorders (which are obviously behaviors)...well... I'm more willing to look under the microscope than in an ancient text.

New Scientist Planet Science. (http://www.newscientist.com/nsplus/insight/big3/conscious/day2b.html)

basically, it says that when we dream, our brain's attempt to make some sense out of the information it is receiving from the brainstem, and the motor cortex therefore sends out signals for movement. because of sleep paralysis, these movements are not carried out, but the efferent copies are still sent out. therefore, the efferent copy is received by the brain, there is no movement, so the illusion of movement is still created.

this reminded me of our conversation about the phantom limbs and how these limbs appeared to be present and in pain, although they had either never existed, or had been removed. however, the phantom limbs felt as though they were in pain because the movement was not being carried out and the brains respose was to interpret this as something wrong and therefore "painful." why is it that our brains do not interpret these dream efferent copies as pain? it seems as though maybe there is something i am not understanding in the mechanism of efferent copies . . .

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Name: melissa hoegler
Username: mhoegler@brynmawr.edu
Subject: something different
Date: Tue Mar 6 02:37:07 EST 2001
Comments:
I just read something that reminded me of class today. It appears in February’s Utne Reader It is the antithesis to the idea that brain equals behavior. The article is an interview with Biologist Rupert Sheldrake. He believes that all living beings act as they do because of nature’s invisible fields (called morphic fields) that have a sort of memory. For example, a rabbit looks and acts as it does, not because of genes, but because of the memory of rabbitness that is present in it’s morphic field. The study of these fields is called morphology. Sheldrake thinks that genes “tune in” to a certain morphic field. The rabbit, for instance, would be tuned in to the rabbit channel. It all a sounds like a bunch of b.s., huh? But, it is a metaphysical look at something other than the idea that brain = behavior. It also is a really logical explanation for things such as ESP and reincarnation.

Here are some links to learn more about morphic fields if you’re so intrigued:

Sheldrake's Home Page

A quick, scientific look at morphic fileds.

Some more stuff on morphic fields. This one even uses "boxes"

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Name: NJ
Username: sophisticatedivy@hotmail.com
Subject: just some thoughts on language
Date: Tue Mar 6 09:10:39 EST 2001
Comments:
I thought it was interesting to learn that many think of language as a form of central pattern generalization. I never quite thought about it in that manner. The idea that children learn languages faster because their brains have neural plasticity never occured to me. Before taking this class I generally thought that the environment and social structure were the reason why children learned language faster than adults. When I think of families that newly immigrated to America and my neighborhood I have noticed that the childrens learn english way quicker than their parents. I though it was because they are in school and they tend to socialize more. However, I can see how neural plasticity has its hand in the matter.

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Name: Mary
Username: mferrell@brynmawr.edu
Subject: Proprioceptors
Date: Tue Mar 6 09:30:29 EST 2001
Comments:
The story of Ian Waterman(www.apa.org/monitor/jun98/touch.html) (I haven't mastered html yet)brings up some interesting questions to me. He is the guy who lost his ability to make automatic movements because of viral damage to his 6th sense, proprioception. His "I" function and visual percreption were able to take over where his non "I" function sensory neurons called proprioceptors failed. Only by watching his limbs can he can make movements like walking and reaching and such.

The interesting observation about his behavior is that he makes gestures while speaking quite automatically and normally, compared to his calculated steps that he controls cognitively using visual feedback. His hand gestures related to his speech can be consciously or non-consciously executed. Sounds to me like motor symphonies coordinated by corollary discharge that evolved with speech. The skill of speech probably involved with the communicative gestures of the hands. But is it an unconscious habit due to corollary discharge. What are habits? And why do some people have this hand gesturing more than others if they are part of evolution? These neurons of automatic hand gesturing and speech seem to be an example of neurons that are genetically hooked up in certain ways to form a central pattern generation. Instead of the alternating movement circuit that we discussed in class, it sounds like a coordinated movement circuit.

Also, the ability of this hand gesturing/speech movement to be conscious or unconsciouly controlled is intriguing. Does this mean that the "I" function can interplay with our automatic behavior? For example, can we as some people claim, interplay consciously with our immune system to make our cells get rid of cancer?

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Name: Caitlin Costello
Username: ccostell@haverford.edu
Subject:
Date: Tue Mar 6 21:09:02 EST 2001
Comments:
Elizabeth mentioned the period of plasticity in language learning, which according to my Psych of Language class this semester is until about 5-7 years. The case of the 12 year old locked in the attic all her childhood was, I believe, Genie (sp?). When she started to learn language as an adolescent, at first people thought she was retarded; however, in contrast to most retarded individuals, who exhibit speech with low vocabulary and high syntax, Genie had advanced vocabulary and very low syntax. I'm wondering what this all means for central pattern generation. You could make sense of it just as a difference in damage to the brain (Genie's left hemisphere having atrophied as a result of so many years without language vs. whatever specific changes occur in other people with brain damages that lead to language difficulty) resulting in different effects on language. But this shift of focus and mastery between syntax and vocab seems like more than an input/output kind of thing; a whole different way of using language, indeed of looking at and understanding the world...it seems to make the CPG notion more complicated somehow, and if language is essential to who we are, throws the whole I-function thing back into this all.

And a general thought on the direction of this class and how we've been delving into the workings of the brain...as long as I'm throwing stuff in from my other classes, I just finished a book called The Differentiated Classroom for an education class. In a differentiated classroom (one that acknowledges and addresses the differences in how each student learns), one thing the teacher must be aware of is that some learn best from a part-to-whole approach, and some from a whole-to-part approach. What we've been doing here with the brain is whole-to-part, which makes sense in that we all know we've got a brain, which is a good reference for then looking closer and closer at the smaller parts of it. But maybe it would be useful to then look at it backwards--once we've got all these parts (the little boxes and such), can we work in the other direction and try to make sense of the whole (the brain) from the parts we now have? Just a thought that might be interesting to try...

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Name: anonymous
Username:
Subject:
Date: Thu Mar 8 01:06:35 EST 2001
Comments:
Contrary to what I once thought, scientific progress did not consist simply in observing, in accurately formulating experimental facts and drawing up a theory from them. It began with the invention of a possible world, or a fragment thereof, which was then compared by experimentation with the real world. And it was this constant dialogue between imagination and experiment that allowed one to form an increasingly fine-grained conception of what is called reality.
François Jacob, French molecular biologist 1988

Distinguishing reality in neurobio is a daunting task. We have a series of semi-autonomous actors in the brain, nerves, and muscles, which we redefine in every class. To understand the reality of the nervous system we have to realize that all the factors work together in a complicated interplay. And that it has some capacity for spontaneous action, versus some capacity for being told what to do by some upstream/outside constituent. Perhaps I become lost in the concepts but I feel in ideas, we are always dealing with a string of words or more elaborate concepts. How do we compare strings? How do masses of nerve cells interact to shape up new concepts from random noise? How do a group of nerve cells get together to initiate a movement? I think these are the questions that are taking a gradual development and ultimately, a better understanding of the nervous system.

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Name: Nazia Ahmed
Username: nahmed@brynmawr.edu
Subject:
Date: Thu Mar 8 01:08:16 EST 2001
Comments:
sorry the last comments were from me. I forgot to type in a name.

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