Biology 202 Neurobiology and Behavior Spring 2004

yeah, so phantom limbs.

im gonna have to paraphrase myself because im so annoyed right now-
basically what i said was that i found the answer to my own question about a biological explanation for phantom limbs. contrary to my assumption that the experience of a phantom limb is an unusual case, it turns out that almost every amputee continues to feel the presence of the amputated limb. the existence of this limb if so compelling that a person will actually try to lift things with their amputated (i.e., nonexistent?) body part. also, there are two "types" of phantom limb experiences: a person may either experience movement of the limb (e.g., swinging while walking)or may experience the limb as being "stuck" in a particular position. for example, one man's phantom limb stuck out in a 90 degree angle from his body and therefore whenever he would walk through doorways, he would turn sideways in order to avoid hitting walls!!

about 50% of amputees experience severe chronic pain in their phantom limb. as a person who deals with severe chronic pain from advanced osteoarthritis, i cant imagine what it would be like to be unable to receive analgesis-directed treatment or similar therapy, due to the fact that my affliction did not involve an actual, tangible body part. i would go insane. it would be as if you got hurt and could not apply ice, or as if you had a nagging itch that could never be scratched...

the most recent biological explanation for the experience of phantom limb pain, is that it results from the "irritation of nerves in the stump", which sends signals to the areas of the somatosensory cortex that used to receive input from the limb prior to amputation. possible treatments include: surgical destruction of parts of the neural pathways between the stump and the cortex, the peripheral nerves and the stump, or various pathways involving "relay nuclei" to the thalamus or somatosensory cortex. unfortunately, these treatments only result in temporary pain relief, which leads to the belief that the experience of phantom limb pain exists in the cortex itself and is therefore much more difficult to address.

so, that was basically what i said although in a much less articulate/much shorter version.

Another thought is regarding people's ideas about languages. English isn't my first language, Cantonese is, although I don't speak it very often. Because I don't speak Cantonese often, I've definitely lost a lot of my vocabulary and comfort with speaking it. I think Maja's mostly right, regarding languages, if you don't use it, you'll lose it. However, I can still understand Cantonese pretty well. I can watch a Cantonese movie without reading the English subtitles. Why is it that I can understand the language, but I can't seem to coherently speak it?

one more thing- i have ADD and i have noticed an important difference between those of us with this issue and non-afflicted people. when i am thinking about or doing more than one thing at a time, i can actually pay better attention whereas i feel as though when "normal" people multitask, their attention suffers. i think that this is an very intriguing distinction. all i know, is that the more i do in class (e.g., reading or writing), the better i can pay attention to prof. grobstein. is this perhaps because as Paul said in class today, there is too little inhibition in the nervous system and therefore excess excitation that needs to be channeled? whatever the reason, it is certainly convenient in terms of productivity and time management!

I felt a cleaving in my Mind
As if my Brain had split-
I tried to match it- Seam by Seam-
But could not make them fit.

The thought behind, I strove to join
Unto thought before-
But Sequence raveled out of Sound
Like Balls- upon a Floor.

The poem describes the feeling of confusion that can go along with neurological disorders. With this in mind we were led to the question of how a person with a neurological disorder figures out that he or she has a problem that needs to be addressed. We also discussed the problems modern medicine creates when patients become so satisfied with their treatment that they no longer feel the need to continue taking the medication. In short I thought it was interesting to get another class' thoughts on some of the topics we have been discussing.

But we don't,, thats the thing. My brother, for exaple, HATES the smell of bananas. It makes him sick. I, however, think they smell great. Also, I like the smell of gasoline, while some hate it. I think you're right that the smell is percieved in basically the same way, since smell is an interation of chemicals with receptors, but that recieved smell is interpereted differently. This is why people have preferences in bleach scents and perfumes.

I like the idea of language not covering the smells, its very 1984, but the question becomes WHY is there no language for this when there is such a rich vocabulary for our other senses?

To throw some other phenomena out... Do people ever have the experience that they've thought something out so well that you think you've said it? Is that representative of my brain's to communicate within itself? Also, I just returned from my Uncle's funeral. I was amazed by the amount of time people could sit looking at each other, communicating without words. As human beings, we often subconsciously weed through the words of a conversation in an attempt to find the emotion underlying. Are our brains built better for physical expression? Is speech just a device that developed to convey this with more detail?

I know this post is a little wacky, but these were just some thoughts that were flying around in my head.

Anyway, to cut a long story short, the people from Deep Space 9 turned the hologram machine off, and discovered the old man was the only person who didn't disappear. He wouldn't let them turn the machine on again, then, and they had a long argument. He kept insisting the the people of the colony weren't real, and he didn't want them back. They were a mockery of the people that he longed for and had tried to recreate, because they resembled them in every way down to the last detail- except that they were neither conscious nor alive. And then this is the ending I remembered today, which I may very well be making up, but I still like it: Their reply to the old man was, how did it matter, that he knew they weren't alive? He was still killing them.

I guess that just caught my fancy because it ties back to that whole idea that we can't know for sure if any of the people around us have consciousness. We could each be the only real person in the world. But the fact is, eventhough that's a possibility- it isn't a useful way to view the world. Our reality may be an illusion, but the most useful way to deal with it is just to treat it as though it's reality. And if someone shows the outward appearance of consciousness, and yet does not actually have consciousness, in a way that doesn't really matter.

Anyway. I probably just mutilated that episode, and for anyone who's seen it and remembers it better than I do (which wouldn't be difficult), I'm sorry. Just one other thing: reading the discussion about language, I had a kind of related thought, about expressing yourself in a language- I've noticed that some people find it far easier to articulate ideas in writing than outloud, and for others it's easier to express themselves outloud than in writing. It's interesting. I've always wondered why that is. It feels as though your ability to express yourself outloud and in writing ought to be the same, but that's almost never the case. There are ideas that I can explain in writing that I find it almost physically impossible to express outloud. The words simply disappear, or get confused and forget where they're meant to go, and the idea itself starts to get tired of waiting about and I start to forget it, and finally all I want is to grab a pen and paper and communicate that way... And then I have a friend who's wonderful at expressing himself outloud. He's intelligent and eloquent and convincing, outloud. But set him in front of a keyboard, and all of a sudden he has nothing to say.

This thought leads to another that I have been struggling with for years. I used to feel a lot of guilt about my life situation. I would read the newspaper and watch CNN. I was confronted daily by the fact that the vast majority of the world's population does not live in the comfort and security that I do. I would often wonder why I deserved to live so well with so many opportunities available to me while many, perhaps more deserving than myself, lived in poverty? I told this to a researcher who I was helping one year and she told me an analogous story of a man who struggled with the idea of free will. He wanted so desperately to know if he was in charge of his life or not, yet every time he thought he had found an example of free will, he would quickly discover that the situation could just as easily support the idea that he had no free will. His inquiry went on for years and nearly led him to a mental collapse. Eventually he came to the conclusion that there was no way for him to prove or disprove that he had free will. So he decided that he would simply believe he did have it and lived as though it were so.

Is it useful to think about something one way for which we have no basis especially if this view is detrimental to our daily functioning? Or is it better to think about a situation that has evidence to support it and makes it easier for us to function? Though no one can disprove that we are not all just producing electricity for machines. I know that I can be a lot more productive thinking that reality is exactly as I and most other people perceive it. Likewise, I am more productive thinking that perhaps I do deserve to be where I am and the challenge for me is proving that this is true.

I have a friend from high school who is a high grade schizophrenic and a generally wild guy (we're talking knocking police officers unconscious while under the influence of LSD, joining a cult kind of wild). Nonetheless, Latrell has always been very interested in the mind and it's capacity to percieve "reality." He read books on magic and the occult, and joined a cult which was loosely based on these principles if I remember correctly.

This past summer, my friends and I had just seen the second "Matrix" movie and we're hanging out on the street talking about what a piece of crap it was. Latrell walks by and we ask him about it.

"What did you think of the Matrix?" I said.

"Well, you just have to deal with it," was his response.

Although not appropriate for the question I asked, his response was adequate for the question we are addressing. If there is a transcendent "reality" that we are unable to grasp, you just have to deal with it, because trying to grasp what is inherently ungraspable is a pretty fruitless activity. The idea of the Matrix is that in order for the Matrix itself to be so sinister and deceptive, we can't know about it. We'd be inside of it, and we'd just have to deal with it until Keanu Reaves achieves a vocabulary large enough to save us.

I was also very interested by the discussion of language, and the notion of the "inner voice." I found this random website called the "skinny on deaf people's inner voice." The question posed was, "do profoundly deaf people who learn to talk have a voice in their head?" The answer was that we can cogitate, daydream and reminisce without employing any language system at all. In fact, random gibberish bounces around in the brain (just like the random firings of our brain that need to be inhibited by our nervous system..). A deaf clinical psychologist responded "the brain has a special capacity to develop phonological representations, even when it does not have auditory input." What one person hears may function as a sound, or convey the same meaning that language would. Also, how is this manifested in dreams? Apparently, Deaf people can have an auditory inner voice as well a signing one. From personal experience (as a hearing impaired individual), I feel pretty confident that I "hear" in my dreams, however I do not know if this hearing is that of a true hearing person or the hearing that I have now. I know I've gotten quite off topic from the notion of language..but I thought it was an interesting question that has always floated around. Do blind people see? Can quadriplegics walk in their dreams? Can we smell in our dreams? We think of dreams as primarily visual, but what happens if we include other sensory elements?

This also reminds me of the feeling (or lack thereof) described by people after the death of a loved one. An ability to "hold it together" and "do what needs to be done" before grieving is probably also a survival adaptation. I'd like to know more about the processes behind this phenomena.

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