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An ongoing conversation on brain and behavior, associated with Biology 202, spring, 1999, at Bryn Mawr College. Student responses to weekly lecture/discussions. A suggested topic was provided, but students were free to write about any other observations, ideas, or questions that particularly interested them.
We've spent a good part of the past week talking about properties of neurons, and will spend at least a part of next week continuing that discussion. Its interesting, in looking through the forum for the past two weeks, that most of the things people are interested in and talking about (e.g. souls, self, consciousness, choice, mental illness) seem rather remote from neurons. Given this, do you think its worth spending as much time as we are on the properties of neurons? Is it likely that understanding neurons better will contribute useful insights into some of these other topics? If so, how?
In speaking of the properties and workings of the nervous system, neurons in particular, I am tending to find myself growing less and less comfortable. Information in general, especially understanding the way something works, has always made me feel very positively. But reducing the very essence of my "being" into changes in membrane permeability makes me very uncomfortable. I am a very complex person, as are all humans, and it makes me feel very unimportant to have all the unique, seemingly unexplainable things that make me "me" based upon things as easily explainable as neurons are.
Thinking as a scientist, I tend to believe that the best way to go about understanding the larger picture is to look at the organization and function of smaller sections and then use this information to learn more about the workings of the entity as a whole. In this manner of thinking it makes perfect sense to spend time becoming familiar with the smallest parts of the nervous systems, the neurons. By understanding the way they process information it would seem that we could learn more about how the entire system processes information.
But looking at my brain in this manner disturbs me greatly. I can not help but remember Monet's paintings. You can look at parts of his paintings in great detail but because they are entirely made up of small dots of paint it will not make much sense. It is only when one backs up and takes the entire picture as a whole into account that the picture can be seen. To me, it does not seem as though the workings of the individual neurons, although invaluable as scientific knowledge, are of much relevance to the behavior that humans are capable of exhibiting. I am, however, fairly certain that this opinion has much to do with selfishness on my part. The fact is that I believe myself to be more complicated and unique than the simple functions of my neurons. I know that it is simply stubborn and probably quite "stuck up", but I can't quite fully accept that these electric signals can account for my countless thoughts and actions. It's something that I don't want to believe without some sort of very strong, very tangible evidence.
One of the most significant general understandings to emerge over the past twenty years or so is the enormous amount of complexity and uniqueness that can emerge from "relatively simple interactions of relatively simple things". This could only really be appreciated with the advent of easily available and powerful computers, because the consequences of most "relatively simple interactions of relatively simple things" can only be determined by repeated ("iterated") calculations (cf. On Beyond Newton), an impossibly time-consuming task without computers.
The general "complex systems" understanding makes it (for some people at least) an entertainable possibility that even something as "complicated and unique" as oneself may come from interactions of neurons. At the same time, the perspective is consistent with your Monet concern: it would not be expected to be the "simple things" (dots of paint, or neurons) that display the properties one is interested in; those properties exist only in the interactions of the simple things. We'll talk about concrete examples of this "emergence" in terms of neurons as we go along.
In this sense, studying neurons is not seeking to "reduce" your "being" (or anyone else's), but rather to specify what properties neurons (the simple elements) have, so one can try and imagine how interactions of them could yield additional properties. The point is actually quite generally relevant for "thinking as a scientist". Taking things apart to see how they work rarely succeeds because some part has the properties one is interested in understanding: there is no part of a clock that keeps time. The strategy instead works (when it does) because on sees how particular kinds of interactions of particular parts can yield what one starting out being interested in. As you say, "reducing" is only part of the process: one needs to keep in mind, both before and after reducing, what it is that one is trying to understand. PG
"Perfectly valid" is fine (though it does raise the interesting question of what is different in your brain in comparison to people who are less comfortable thinking of themselves in terms of neurons). But then what do you expect you can learn by studying neurons, as opposed to observing behavior? Why study one as opposed to the other? PG
My family was discussing the reaction of my 12year old son's teachers (negative) to his choice of the guillotine as a topic to write about as an example, for better or worse, of an invention that changed people's lives. Aside from the fact the aforementioned 12 year old was being a smart alec, it got him thinking about the movement over history to make executions more human and consequently lead him to think about some of capital punishment many issues.
The older kids, an almost 17 year old daughter and a 19 year old son (home from college for the weekend), related a tale that they had heard when they were around the little guy's age. The story was something to the effect that a person who was about to be beheaded by the guillotine was requested to blink his eyes three time after the blade had been released and his head severed to signify whether it was, as one might expect, a painful experience. Well, according to this "legend" the unfortunate person did in fact blink three times after his head was separated from the rest of his body.
I too, like the kids, might have found this to be just another piece of gory lore had it not been for our class discussions of last week about the sensory receptors that are in the spinal cord and how they can transmit sensations and cause reactions even there is a disruption between the spinal cord and the brain. And also the discussion about how the nerves that control the functions of the face (speech, eyes, nose, etc) and those related to olfactory and optic nerves being contained in the head and brain.
Yep, an interesting and appropriate question, if a little macabre. Here is one effort to trace down the facts of the story. And another. Found by searching hotbot.com using "guillotine" and "blinking". Pretty much fits what we'd expect, given known neuronal organization, no? PG
Moreover, if we want to understand how brain affects behavior, as opposed to conjecturing that they are identical, neural function is an important place to start. The book gives an example of how Parkinson's disease affects dopamine release. Additionally, the "battery model" helps show us how signal transport affects voluntary versus involuntary movement in people who are paralysed. We know that the neuron connection is severed, giving us an exact picture of the cellular roots of the disability. Hopefully, with an idea of the problem, neurological research can lead to a restoration of normal behavior. Empirical research and development is the proper purview of science and technology, and it is much more comforting to study the nervous system with observation, rather than speculative
I certainly don't want to trigger a new round of debate at this point. But three general thoughts about science. "Brain=behavior", at least on my part, wasn't "speculative"; it was an effort to summarize, in short form, a large array of observations, and the trend of those observations over time. Which is to say, it was an empirical statement, in two senses. First, it summarizes empirical material. Second, it motivates the collection of new empirical material, an essential function of summaries. Whether knowingly or not, all scientists proceed this way, by the testing in new domains of summaries which work for observations to date and make predictions about observations yet to be made. By so proceeding, science has frequently treaded into the "normative" (Galileo and Darwin come quickly to mind). As as "empiricist", would you have it shy away from such encounters? PG
Regarding this week’s topic....I see a usefulness in studying the dynamics of an individual neuron mostly so that we can understand how billions of them interact. I agree with Emma in the sense that I have difficulty relating complex social behavior to the influx of sodium into a cell. But examining the web of neurons which make up the brain could help explain behavior in terms of the box model we discussed. The number of neurons and the number of connections involved in brain activity is well beyond our comprehension. Even though I don’t see how chemical and electrical activity could allow for our behavior, experience and sense of self, I accept that this is our best attempt at understanding such phenomena.
I don't know what the situation is with hunger in quadraplegics, but its an interesting and appropriate question, perhaps worth trying to explore further. One complexity that would need to be looked into is that many visceral signals actually reach the brain via cranial nerves, rather than via the spinal cord. One would want to know how many of these are intact, and what signals they are carrying.
More generally, it sounds like you, Emma, and I all agree that the next step after neurons ought to be to see what kinds of properties emerge from interconnected groups of them. PG
A topic I would like to explore for my paper is the effect of various “anti -depressant” drugs. The very idea that such drugs exist pin points to the validity of brain=behavior. I do not know anything about how these drugs work to “cure” depression and weather they actually do or not. The fact that a chemical substance is used to affect someone’s state of mind is thought provoking.
A definition worth noting states that depression is “a psychoneurotic or psychotic disorder marked esp. by sadness, inactivity, difficulty in thinking and concentration, a significant increase or decrease in appetite and time spent sleeping, feelings of dejection and hopelessness, and in some cases suicidal thoughts.” This is the shortest description I could find! What struck me most about it was the long list of extremely complex behaviors which together mark the state of being depressed. So how do the popular anti- depressants such as Prozac, Redalin, and Zoluft (to name a few) affect one’s “state of mind” (brain?) which is involved in “the concept of self”?
I just read in my chemistry book that the rate of chirping of crickets and the flashing of the fireflies about doubles for a 10 C increase ( I wonder if the Harvard Law of Animal Behavior holds in this case). The increase of temperature speeds up chemical reactions. Therefor, the proportional increase in chirping suggests that the psychological processes which govern the degree of chirping must involve chemical reactions originating in the brain. But chirping is no where close to the complexity of behaviors involved in depression. So could it be that these drugs affect a person’s “state of mind” (brain) by altering the rates or reactions themselves? I am not sure I can get a direct answer to this but there must be something regarding how the drugs work since so many prescriptions are written every year.
If anyone has any information or knows a good website on anti-depressant drugs and their affects on the brain please let me know. Thank you.
I enjoyed our conversation about this, and hope you did too and have now at least some places to start. The question of how one chemical can have multiple behavioral effects is an interesting one. A few other thoughts that just came to mind. You might want to look back at Melissa's posting last week, since it further complicates the problem: medication is effective in some people, not in others. As for your thoughts about temperature/cricket chirping/state of mind: extremes of temperature certainly affect state of mind in humans, so too do levels of oxygen and amount of light. Those kinds of effects might well be worth looking into further in connection with the brain=behavior question. PG
It is very much worth our while to spend time on the properties and functions of neurons. Neurons are the building blocks of the brain and brain function. They explain how the brain works and what chemicals are present. Research that leads to treatment would not be possible without the knowledge of neurons.
My paper might be on the relationship between Tourette's Syndrome and Obsessive Compulsive Disease which are both thought to have a common link in that they both involve a dysfunction is the basal ganglia. Another topic I am interested in drugs such as anti-depressants, serotonin uptake inhibitors, neuroleptics, and MAO inhibitors and the side effects they have on the patients who take them. I am interested in the way that medicine effects the chemicals in the brain and other forms of therapy such as cognitive behavior therapy, aversion therapy, the former use of shock therapy, brain surgery and other ways to combat neurological disorders.
That's a rich array of topics. Be sure, after exploring, to focus a bit for your paper. Remember you'll have two more opportunities, so you don't have to do everything at once.
Neurons as the "building blocks"? So it is usually said (and we are presuming so in class). But are there any particular reasons why we should focus at that level, instead of, perhaps, the level of molecules? or that of some larger box (collections of neurons)? PG
The idea of behavior fascinates me and although I would like to know about the larger workings of the nervous system, I realize that it is necessary to first comprehend the simplest aspects of neural communication (which, at least to me, do not seem to be so simple).
I have really enjoyed the classes this past week and have found the book helpful in outlining the basic topics that we have discussed in class, such as the resting potential. Thus far, I have found studying the processes of neuron communication to be very interesting. I look forward to continuing the search for answers to the many questions that we all have about behavior.
Me too. And indeed we need to know about the smaller components to help imagine what the bigger components can do; no, they are not "simple" but are "simpler" (see my response to Emma. But let's not be "too" safe (see my response to David). And maybe it will turn out we can be appropriately "scientific" about some phenomena above the level of cells? We'll see. PG
This also relates back to our model of the nervous system as an input/output box which contains several smaller input/output boxes, etc. I was wondering if perhaps the functional modules which cognitive neuropsychology assume to exist within the brain can be thought of as such input/output boxes.
As for this weeks topic.... I still believe in the assertion that the brain equals behavior and I believe that, as long as I take such a perspective, I have an obligation to study and understand the properties of neurons. While the study of neurons may seem small and insignificant in relation to the bigger issues regarding souls, self, consciousness, choice, mental illness, etc., the only valid scientific approach to the study of these issues seems to be to start by understanding the phenomena on the most basic level - that of the neuron. I think that that, eventually, we will be able to apply that knowledge to an understanding of the broader phenomena we have discussed.
As I said last week, there are great similarities between our in class interconnected boxes approach to the nervous system and the general neuropsychology perspective. The fit is noteworthy, and certainly inclines one to ask, as you do, whether the neuropsychologist's functional modules correspond to nervous system input/output boxes. At the same time, I tend to get nervous about ideas which I take for granted. While looking for fits between neuropsychology and nervous system boxes, I'm inclined also, as I said last week, to look into the question of whether there may be alternative ways to characterize both the nervous sytem and cognition. Want to join me? Here's a possible starting place.
I'm not sure I agree that neurons are "the only valid scientific approach" to understanding behavior, and very much doubt most neuropsychologists would agree. At the same time, I do think the properties of neurons both yield some direct insights into behavior and help to both motivate and constrain the kinds of higher order models one entertains. PG
At the end of Thursday's class, Prof. Grobstein said that action potential is not an electrical signal, but instead a change in membrane permeability. Therefore if brain equals behavior, things shouldn't happen instantaneously, but instead need time. I'm not quite clear how this philosophically sheds light on the b=b discussion. The only conclusion that I can make is that it might allow for some degree of thinking. For example, a computer utilizes electricity for communication, yet it still cannot make choices based on past experience, or an ambiguous decision (ex. Choosing between two equally good things). Computers can process information instantaneously, yet have no power to perform cognitive tasks. Organisms on the other hand need time to process information, but have the power to perform complex cognitive tasks. Therefore I might conclude that the necessity to process information over a period of time contributes to the concept of choice and personality…. I'm really only making a stab at this. Does anyone have any ideas?
See my response to David for some thoughts on "philosophy" versus biology; they're not so distinct, either at the outset or in the outcome. There are a variety of interesting issues relating time to brain/behavior. The one I had in mind was historical. In the latter part of the nineteenth century, one of the important observations from which "experimental" psychology was born was the demonstration that "thinking" took time. The finding encouraged the idea that "thinking" was a physical process (as opposed to a "mental" one) and hence could be studied objectively. Your thought is an interestingly related one. We'll talk more about computers in comparison to brains, and there are certainly differences. Its not true though that computers (these days) can't make choices based on past experience or perform at least some "cognitive" tasks (see, for example, "Simple Networks, Simple Rules: Learning and Creating Categories"). Nor is it quite true that they "process information instantaneously". While individual steps of processing are quite fast (much faster than in the nervous system), they do take time, and lots of steps are typically needed for a given task, so the input/output times for a computer can be appreciable. Maybe brains take time because thinking involves lots of steps, even if we aren't aware of them? PG
Yeah, but we have to make some choices, set some priorities, no? Why neurons, as opposed to molecules or groups of neurons or whole people? Presumably because there are some reasonably close relations between neurons and behavior? which show things it might be hard to appreciate by looking at something else? Actually, memory is an interesting example in that regard. If the nervous system is behavior and the nervous system is simply a large number of interconnected neurons, then it would seem to follow that memory must involve a change in either neurons or their interconnections, no? There are some relevant Scientific American articles on your syllabus list (Kandel, Mishkin and Appenzeller), and a good review with more recent references in Chapter 24 of your textbook. We'll talk more about this. PG
As a psychology major, we have already learned about the different lobes and regions of the brain that are more or less implicated in memory, self awareness, and such. I do feel by breaking down the nervous system into neurons we are learning more about how all the parts work at a more intricate level, and this is valuable to the scope of the course. I don't believe it will help us figure out potential components of a "mind" or "soul," however, in the brain. Topics such as self, consciousness, choice, and mental illness can be understood in terms of neurons, so, in that sense, the study of individual neurons is a valuable one to the course. Perhaps, though, the topic of whether or not there is anything more than the nervous system and the brain (such as soul or mind) should be put on hold until we completely learn all the biological facts, and then the question could be retackled on the forum.
Fair enough, but with one proviso? I'm glad souls and minds came up at the outset. A large part of the significance of science lies in making better sense of general ideas that people have by showing that what seems a single, simple thing is actually a number of different interacting things. The general ideas are important to motivate science, and science in turn helps to understand the general ideas. So let's keep "mind" around, at least, and see what sense we can and can't make of it with neurons, circuits of neurons, and brain lobes and regions, ok? PG
I am hoping in my paper to discuss the effects of a contraversial drug... maybe Melatonin. Examine whether or not it truly is a myth and how exactly it is supposed to affect the brain and our behavior. But this is just a preliminary idea.
You raise an interesting question. If each of us is different, does that necessarily mean our neurons, the building blocks of which we are made, are different? It isn't necessarily so: one can build two quite different buildings using the same bricks. Let's keep on eye on this as the course goes on. Are differences in people because of their neurons are different, or because they are assembled differently, or both? Sorting out myth from reality about drugs is a tough but worthwhile activity. PG
At this point, the part of the explanation that I do find boggling is the idea of how FAST this process of depolarization and repolarization must be happening. Even as I think of these sentences and physically type them on the keyboard, so many connections are being made in my nervous system…in its scope and speed, it is incomprehensible. Each movement of each finger on the keyboard is due to countless ions being moved back and forth over countless membranes. Is there a way of comprehending the exceedingly fast movement of molecules in our bodies?
On a different note, I have a general idea of my paper topic. I am planning to write on the neurobiology of learning disorders, probably focusing on either dyslexia or ADD. I would like to understand the differences in neurobiology that manifest in these types of symptoms, particularly as they relate to sequential and rational processing. A preliminary search on the internet shows that there are lots of web sites devoted to learning disabilities and that many of them have extensive links. I am a little concerned about finding good scientific discussions of these topics, and not just “layman’s” information. Any suggestions would be welcome.
I share your sense of fascination with the "big, booming, buzzing confusion" that seems to underlie the apparently much simpler and stable things that we are and do. And, of course, you'll find that (coincidence?) on the web as well. A little playing around with search terms and web-surfing can usually turn up something deeper than just "layman's" information (though that can sometimes be instructive too). Here's an academic link on language disorders, with links on to other sites (usually a good indicator of quality). PG
Its actually an interesting question: why start with neurons rather than with molecules? or atoms? or quarks?
Yes, of course, genes are relevant to our discussion, and we'll be talking about them in sessions to come. In the meanwhile, I'll be interested in what you turn up, since the genome/environment interaction is one I've been interested in for a long time (here is how I was thinking about it a few years ago, and here and here a bit more recently).
One of the nice things about the nervous system is that it is studiable in a way that can make the gene/environment interaction more than "comfortable, neutral, and scientifically safe" middle ground. "Neural networking" is demonstrably influenced both by the genome and by experience (as we'll see). Moreover, there is an interesting numbers problem associated with thinking about the nervous system as being determined by the genome alone, at least in any simple sense). There are many more neurons than there are genes, and vastly more neuronal connections. PG .
And further in class discussion, which we will have. Yes, many amputees report feelings in missing limbs and we'll talk about how and why this might occur. I wasn't aware of the phenomenon for paraplegics, and would be interested in knowing more about it since it has some interesting implications for neuronal processing. Thanks for raising the issue. PG
As for my interests on the first paper, I was considering two things. The first deals with surgically splitting the brain by cutting the corpus callosum. I have done a little reading on the effects on the patient and it is very interesting. As I was reading, after a patient received the surgery she was asked to reach underneath a table with one hand and felt a fork. When she reached underneath the tabel with the other hand, she said she did not know what it was. I thought that it was interesting how that worked out. The other subject I was interested in was acupuncture. Well, I was first wondering how the entire notion of acupuncture works after someone posted the "pins and needles"title. It got me wondering if acupuncture has to deal with the Nervous System at all, because it is suppose to be a healing technique. My questions will be if it does effect the Nervous System, and if so, how does it work.
Everyone, without exception in my experience, needs to work through action potentials several times before they make sense. I'm glad our going through it helped. You got it that the current does indeed flow in the "opposite direction"? But that that has no effect because of sodium inactivation?
Behavior following callosum section raises a number of interesting issues; so too, of course, does acupuncture (and any of a number of other therapeutic techniques that predate "modern western medicine"). Either would make a good topic, though, particularly for the latter, you'll have to do some winnowing of web materials to get to something reasonably concrete and observation-based. Have fun. PG
Although we haven't had many classes so far, I think that this class has already challenged me to look at the brain and it's behavior in new ways. It was helpful to first present a general outlook of behavior, instead of starting of with all the complex material. Now that we've had many discussions about behavior in general, it makes more sense to be able to focus on the details, and to have an understanding of what we're trying to find about the brain and its bahaviors.
For my first webpaper, I'm interested in looking into how the brain processes visual images and the mechanisms that follow. I haven't yet picked a specific topic ... possibly blindspots? suggestions?
I'm pleased you're feeling challenged, and ready for the details. Vision is a BIG topic, but you can certainly start looking into it, and narrow down on things you find particularly interesting. We'll be talking about it fairly extensively in class in a few weeks, and there is an exhibit on blindspots on Serendip. There's also a Scientific American article by Ramachandran in the list at the end of your syllabus. PG
Echoing what many others have said, I, too, believe it is necessary (and interesting!) to look at the functioning of the nervous system based on neurons, their chemistry, etc... Indeed, it is quite amazing to consider all of the varying capabilities of these tiny cells.
I have recently been thinking a great deal about what I would like to write my paper. I can't seem to separate myself from earlier discussions of soul/mind, etc... so I was thinking it would be interesting to research studies on the effects of faith on rates of healing. I have heard stories (studies? reports? simply anecdotes?) that people with a high level of faith and who use concentrated meditation would heal at an amazingly higher rate than those who do not. The issue here is, as a neurobiologist, how does one explain this? Is it simply the placebo effect? And, even if it is, doesn't that help to prove the amazing power the "I" (or mind or soul?) has over the brain? over every single little neuron we are studying?
Another interest of mine is the effect of alternative methods of healing such as holistic healing (herbal remedies, massage therapy, acupuncture, etc...). How do these methods work? Even more specifically, I am interested in midwifery and the psychological differences between giving birth in a hospital vs. in one's home or a birthing center. How does touch (of the husband, midwife, etc.) affect the birthing woman's brain, easing pain and enabling an easier birth? Perhaps these ideas seem a little bit more "out there" than others being considered, but I am willing to accept that.
Anyone else out there have a similar interest in the unconventional??
Sure, I've always been interested in the unconventional. Any or all of the above. And, for any or all of the above, the same two questions. First, is there good observational evidence that the phenomena exist? Second, as you say, "as a neurobiologist, how does one explain this"? For much of the unconventional, there isn't a lot of good neurobiological study. In these cases, what is needed is some understanding of how the people using such therapies understand how they work, and then a reasonable effort to translate that into a neurobiological explanation that could be observationally explored. Are you up for the challenge? Go for it. PG
Fair enough. But see my responses to Emma and David and Kim, all of whom seem to agree with you. I still think its helpful, for understanding both the nervous system and behavior, to see the different ways people approach the problems at the outset, and to recheck as we go along. PG
In response to Professor Grobstein's question, I'm with all the folks in favor of learning the properties of neurons (I think that's everyone). Since the brain is one organ made up of one type of cell (with a few variations), we'd better under stand how that cell works if we are to figure out how the brain functions. Since the nervous system works via intercellular communication, we need to figure out how that communication happens by looking at the brain a the cellular level.
Re blinking: see my response to Debbie (I assumed she meant by implication what you laid out more clearly). Yeah, everyone seems to want to know about the properties of neurons. Wonder why? In some circles, its strongly argued that you don't have to know anything about neurons to understand behavior. Oh well. PG
And so it does "spread light on various motor disorders/difficulties (see, for example, Research Updates, from the Muscular Dystrophy Association). What about "normal" behavior; do we get any insights into that? PG
Understanding neurons can lead to the understanding of how signals are transmitted throughout the body (as is being discussed in class). Also, understanding the "building block" of specific structures and materials in the nervous system can lead to a better understanding of what all these parts "do" with those signals. How do neurons store memory, elicite thoughts, control the body? And in the case of illness, how does one recognize and repair damage that may have been done?
As a sort of diversion from the strict pro-neuron discussion campaigne, I find myself wondering "how" I think. How do I remember? How do I learn? How do action, resting and other potentials lead to signals which lead to memory and thoughts? Is there something more? Is it the signals that are differeing, the neurons themselves or both? Hoes DOES one think? I think the dictionary is rather vague in their definition of it as "to have in the mind". What does that mean?
Another side note: I saw the movie "At First Sight" over the weekend. That movie had me thinking about how one learns to use their eyes or any of the sense organs for that matter. When the blind man in the film is finally able to see his brain can not process anything that is coming in through that sense organ. He had to learn as a baby learns by exploring and relating. And another thought occurred to me as well. How would one explain "seeing" or hearing to some one who didn't have that capability. Their brain would have no concept of what it meant to see or hear. That's hard to imagine.
See my response to Kim; "memory" and "thinking" are among the terms which looking at the nervous system usefully shows to break down into a number of different interacting processes. So keep the terms in mind as we go through the semester and see what aspects of them we can and cannot make sense of at any given time. Yes, "to have in the mind" is a little vague, as you say; maybe it will be different a hundred years from now? Have a look at the Machinery of Thought, for one approach to the matter. Chapters 22 and 23 of your textbook talk a bit about both learning and memory and how one "learns" (and doesn't learn) to see. There are also some relevant Scientific American articles under "Genesis of neural function and behavior" in the list at the end of the course syllabus (see also Kennedy, Loftus, Plomin and DeFries at the very end of that list). We'll be talking more about this at various points in the course. PG
I don't know what I want to do for the paper yet, maybe brain damage at birth and how it can affect the person as they age into adulthood. My aunt is profoundly retarded and I would like to find some answers as far as what is going on inside her brain or what is not going on...
That's not a bad place to be for the semester: "stuck on the B=B question". And maybe for a lot longer. And the "tangible/intangible" distinction appeals to me as a starting point. As long as one keeps in mind that it can be "many different neurons" interacting, rather than one that helps make the intangible tangible.
"Brain damage" is, as you can probably imagine, a catch-all term which, in terms of neurobiology, can mean a variety of different things (you can get a sense of the complexity of the subject from a bibliography on "Rehabilitation of Persons with Traumatic Brain Injury". The same may well be true of "mental retardation" as well. You can get a sense of this from information and links provided by The John F. Kennedy Center for Research on Human Development, at Vanderbilt University. The Arc is a national organization on mental retardation, with lots of links to other sites. PG
The study of neurons and how they interact seems to me an affective in realizing how the nervous system is directly tied to behavior, something which is seen as so incredibly complex and of such great importance to individuality. Especially when the individual is such a large part of the basis of our society. Yet when broken down into 10^12 separate neuron the combinations seem great enough to make up of the worldly population of humans and other organisms. Still even though I can fully accept the fact that a human being, being viewed in terms of species or as a case study, is composed so many tiny pieces, it is very hard for me to imagine this of myself or the people I interact with daily. That the ability to identify my thoughts as my own, and to recognize other beings is due to different arrangements of the same cells.
To think that I am writing this and analyzing my own personal view on the nervous system using these exact same cells that I a writing about exhausts me. How can something so tiny enable its composite to ponder itself directly? We are in essence, throughout this whole class using what we are examining as tools. I am aware constantly that the signals being sent to my fingers at this moment are controlled by something that seems so utterly out of my control. It is impossible for "me" to imagine the organization of 10^12 separate units, though on almost every level what comprises that "I" is exactly those units working in perfected coordination. A coordination that was being perfected long before that I was able to exist, or our physical selves existed. This reaches far beyond my understanding of the universe, but if over the course of evolution these functions have been becoming perfected in other beings how much of what we consider ourselves is truly us. What is personal and individual which is not just a culmination of past existences, each of which became adapted to similar situations to the ones we could face at any moment, thus had a need for "our" facial expression, motions or thoughts. What we may consider our singular personality is simply just a combination of parts, which everyone shares, differing or not differing according to the need of that being. By this way of looking at things is there a possibility for the individual to exist, or is the concept of individual simply a necessary formation of neuron connections that exist in all humans.
A fascinating set of thoughts, well worth continuing to mull over and dissect as the semester goes on. Yes, there is enough there to help make "tangible" the intangible "indivduality". And yes, it is hard for "I" (what's that?) to imagine what is going on to make/support it (a useful insight which may help to make sense of "I"). And indeed we are "using what we examine as tools". Maybe that's the key in thinking about your question at the end (I assume its a question, though the question mark is missing)? By using the thing, we change it? And different people choose to use it in different ways? So, we each contribute to our own individuality? PG
When looking back at the first days of lecture, I began to review the long list of things that we believed to define behavior. Amongst this list was the act of dreaming. To me, dreaming has always been an enigma. As much as there are many scientific explanations for this act (such as the role and function of certain structures in the brain) they still do not explain why we dream and why we dream what we do. Through the years, it has come to my attention that many of the pivotal scientific theories, artistic masterpieces and works of literature have actually come into being in the process of dreaming (Einstein's theories of relativity, Otto Loewi's experiment determining the chemical nature of synaptic conduction, etc.). I would like to know how our definition and model of the brain and nervous system (with their input/output boxes) account for these dreams. I would especially like to learn how neuronal/ axonal conduction and all of the mechanisms of action and resting potential play into such phenomenon. At this point, I can only come up with very inadequate and abstract explanations for dreaming. From what I can remember, Plato surmised that every human consists of a 'soul' which previously dwelled in the world of 'ideas'. The world of ideas contains all of the ideal figures of earthly entities as well as true knowledge of the world. The 'soul' as such knows of the world and the ideal. He theorized that the individual human's job on earth was only to uncover or remember what the soul already knows. Perhaps dreaming is a mechanism for the remembrance of knowledge already innate.
Julian Jayne, an author who studied the origins of consciousness, suggested that our 'ancestors' (ancient Greeks where his example) did not posses a fully developed sense of consciousness, as their brain was at a different stage in evolution. Due to the 'underdeveloped' or unformed structures in the brain, he believed that they acted on auditory and visual hallucinations in order to make decisions and act on 'free will'. He suggests that the characters described in the Iliad and the Odyssey took advice and orders not from various major and minor gods, but their own self induced hallucinations. Perhaps the act of dreaming displays a remnant of this process of gaining knowledge and action through 'hallucinations' or internally created images and sounds. Another more plausible explanation would be the idea that dreams act as a form of subconscious mental organization. Through this subconscious organization, knowledge accumulated over a lifetime could take on a revolutionary form. In this case, dreams organize knowledge into a logical, productive and coherent pattern that can be effectively used by the conscious brain. But how do action potentials and various neuronal activities do this exactly?? Needless to say, I am hoping that knowledge of the workings of the basic building block will explain the products their mass function.
Thanks for bringing Plato and Jaynes into our conversation. And, of course, dreams, which I too think are important to try and make sense of. We'll have more to say about at least Plato's forms and dreams as we go on. In the meanwhile, here is a listing of on-line papers from the laboratory of Alan Hobson, whose laboratory takes a broad neurobiologically-based approach to sleep and dreaming. Dreams "as a mechanism for the remembrance of knowledge already innate"? Let's talk more about that once we've tried to make tangible the concept of innate knowledge. "Gaining knowledge ... through 'hallucinations' or internally generated images and sounds" sounds more like the way I usually think about dreams. How is this different from "organize knowledge into ... a coherent pattern that can be effectively used by the conscious brain"? And why is this "more plausible"? To explore further. PG
Last week we discussed uncoordinated or independent functioning of different parts of the nervous system, including examples in which neural activity responsible for the "I-function"/self awareness seems not to be coordinated with other neural activities. For example, for a quadriplegic there is sensory activity but not experience. Conversely, a schizophrenic has experience without sensory activity. In these cases, the "I-function" seems to be completely disconnected from other neural activity in a way that prevents conscious interaction with the external world.
This disconnection between experience and sensory activity also seems to be found in what is called Multiple Personality Disorder (MPD). Sybil, Eve Black, and other less well known people with this condition seem to have "compartmentalized" I-functions or multiple seperate "selves" who seem to exist as independent pieces of the nervous system These selves do not always have conscious awareness of each others activities. In this situation, there is a connection between sensory neural activity and the awareness of experience but not necessarily for ALL of the selves at any given time.
Do the separate selves present in the nervous system of a person with MPD correspond to separate networks of interconnecting "boxes" within the nervous system? If so, do these seperate systems of boxes correspond to seperate "people" with all the rights and privileges we associate with "personhood"? Do they have separate souls?
MPD seems like the extreme of the "compartmentalization" of conflicting thoughts/emotions that David mentioned last week. Even typical people seem capable of containing within their "being" a host of completely unrelated and contradictory beliefs/behaviors etc, which come into play at different times. I suppose this struggle is the part of the human experience that makes the Jekyl & Hyde theme so recurrent in myth/art, etc.
I wonder if it is possible to understand these contradictions as relatively separate sytems of boxes that CAN be accessed/modified by other systems of boxes, but can also continue to exist WITHOUT modification by input from other networked boxes. I talked with a man who told me about his training as a bodyguard. He described the number of times he went through drills or simulations in which he placed himself between a person he was protecting and an attacker. He believed that by repeating this protective behavior in many different situations, many different times he established a pattern that would allow him to act without thinking. "If I thought about it," he told me, "in a situation of real danger, I wouldn’t step in front of a bullet." This sort of training seems to rely on the fact that neural pathways between "boxes" leading to altruistic protective behavioral output can function without interference from those that lead to self-protective behavioral output. Maybe the self-sacrificing behavior can take place without conscious control or communication with "I" – "without thinking."
You're making some quite interesting connections between our discussion of the disconnection syndrome in quadriplegics and and some additional phenomena which might be usefully looked at in similar terms. And yes, I agree that "compartmentalization" is a feature of "normal" behavior as well as something that turns up following brain damage. Thanks for the bodyguard story, which highlights another issue we'll discuss at some length: how many boxes do or do not communicate with the "I-function" and how effectively do they do so under various circumstances. "Multiple personality disorder"is currently termed "dissociative identity disorder" and usually talked about in relation to "trauma-generated disorders", which tends to make it somewhat controversial. Leaving the latter aside, I'm curious about the extent to which what is called MPD/DID can or cannot be usefully thought about using the quandriplegic metaphor. The International Society for the Study of Dissociation and the Sidran Foundation give links and references, if anyone is inclined to try and follow this up. PG
I spent some time looking at web sites for my project on epilepsy. I found a lot of information on the topic. The web sites I visited were The National Society for Epilepsy in London and the comprehensive epilepsy management center at the Albert Einstein College of Medicine and Montefiore Medical Center website.
Several topics caught my eye, but the one that seemed most related to our recent lecture topics on neurons was vagus nerve stimulation, which is the mild electrical stimulation of the vagus nerve as a treatment to reduce seizure frequency in some people with epilepsy. The vagus nerve is one of many nerves carrying messages to and from the brain. The nerve fibers are thought to be connected to the areas in the brain involved in producing seizures. The brain waves from these regions are normally well-organized, but during a seizure they become disorganized and the stimulation of the vagus nerve may be able to intercept this abnormal brain activity.
This form of treatment is interesting in relation to our lectures because it really brings home the point that the neurons are conducting electrical current. The comparisons Professor Grobstein is making to batteries are hard to visualize because I think of batteries as part of a flash light not as part of my nervous system. When I read about the electrical stimulation of a nerve by a battery operated generator the point seemed to be driven home.
I would really like to find more information on the details of the abnormalities in the brain of epileptics at a neuronal level, but have not found any yet. Most of the web sties are written to be used by a patient so the problem is explained without detail and without a lot of "science" jargon. I am really enjoying my search though.
Thoughts seem germane for this week (even if triggered last week), so I'll just leave them here. Glad the "battery" proves useful, and the vagus nerve treatment connects to some things we'll be talking about in weeks to come. And glad you're enjoying web-surfing. For details at the neuronal level, try some combinations of search terms, like "epileptogenesis" and "neurons" or "channels". Good luck. Hmmm ... just found the following in a speech by the chairman of the Epilepsy Foundation's professional advisory board: "A key question for research is what makes a brain cell (a neuron) subject to the abnormal firing that causes a seizure? Although much has been learned about how brain cells work, that question is still unanswered, but it may be in the 21st century.". Sounds like there may be a good reason why general references explain "without detail". Regardless, there's a lot of work on the subject; the Epilepsy Foundation has news reports and other links. PG
The idea of a Self, of the "I", and choice are all intimately linked to neurons as well. We have discussed how the brain houses an "I" function by using a quadriplegic as an example. Studying neurons and the types of neurons damaged in the quadriplegic helped us to better understand the "location" to some extent, of the self. People wax philosophical on the "I" and the self and their individuality, but perhaps through a better understanding of the neurons and the nervous system overall we can see how these things can reside in the brain and simply be functions of the vast collective of neurons.
In order to understand at least a bit of how such concepts as the self are functionings of the brain, we must understand from the smallest part outwards the collection of "boxes" that we are using an analogy to the nervous system. The neuron and its components are the smallest boxes we can study, and we should understand these well before moving onto more complicated connections of the nervous system.
Actually we could, as several people have pointed out, study smaller things still, but maybe neurons are the smallest thing with properties close to what we're interested in. And hopefully, studying neurons and their interactions would not only help to show how things like "I" and "individuality" "can reside in the brain" but give us some new and useful understandings of what we mean by those terms. We'll see.
PG
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