Anatomy, Physiology and Neuroscience

I somewhere read the argument that the cells of the human body are continuously being replaced by new ones, so that after some period of maybe 7 years you have a completely new body. Because of this, the argument goes on, the world can't be completely material and there has to be something like a soul, because your body has been exchanged but you are still the same person. What do think of think of this argument? I also read somewhere that brain cells are indeed the only cells that are not being replaced (and that explains why brain damage is permanent). Can someone clarify this? Do you have the same cells in your brain from birth to death? Another thought I…

There is this story of a boy who had half of his brain removed because of serious damage, but developed quite normal afterwards. Information can be found here: http://news.bbc.co.uk/1/hi/health/880478.stm And there is also a book about his story and his rehab: http://www.amazon.com/exec/obidos/tg/detail/-/0521783070/ EDIT: I just re-read the two links and I think those are in fact two different boys - one named Harrison and the other named Nico. Well, whatever, doesn't really change anything regarding my questions. Very interesting story, but I recently had some additional thoughts about it. The brain seems to be most important regarding consciousness - but w…

This is quite a specific question, and I'm not entirely sure how to word it, but I'll try to keep it simple and see if it makes sense! When you touch your finger, the nerves in it tell your brain that it is your finger that you are touching. When you touch your leg, your brain is told that it is your leg. My question is: How are the signals from the nerves transmitted to the brain in such a way so that the signals from your finger are different from the ones from your leg? Does anyone know if they are modulated in some way, with headers and data packets, like computers use? What is the bit-rate and propagation speed of these signals? Any information would be …

Why do you Yawn? No one can ever give me a definite answer.

Can anyone tell me the composition of the Schwann Cells that makes them unique the way they are?

Hey guys, This has been bothering me for a while now. What are we made up of? Everything can be broken down into elements right? Well, what is my skin made out of? What are the muscles in my arms made up of? I tend to think of them as being just skin and muscles, but its gotta be more then that.

I read this interesting article (albeit no conclusion) on why yawning is contagious on the 'world-science.net' web site. Does anyone have any theories on this strange behaviour. I'm wondering if it is a reaction that has mutated from primitive man or primates. A group reaction that is no longer needed so has mutated into something that seems nonsensical. My other theory is that if someone is sucking a bit too much air from their immediate vacinity, the other person yawns to compensate for the sudden lack of air. ;-)

I had an idea. I want to know what people think of it: Do you think that one of the main reasons computer engineers have been having trouble mimicking the human brain is simply because computers are digital while brains are analogue?

Well, this is my first post, and I hope someone likes it. What I am currently working on is writing a paper on the possabilities of disabling negative behavior through reconstruction of the human brain by administering a concentrated plant extract to disable negative neural transmissions. Of course, so far my theory is quite vauge, but cut me some slack, I'm 16. Anyway, when a neurotransmitter binds to a receptor on the postsynaptic side of the synapse, it changes the postsynaptic cell's excitability, meaning it makes the postsynaptic cell either more or less likely to fire an action potential. If the number of excitatory postsynaptic events is large enough, th…

Has there ever been any testing done with pheromones and homosexuals. By nature, a man/woman should not be effected by pheromones emitted by another man/woman. Given that a homosexual is attracted to members of the same sex, will a homosexual actually experience a physiological effect from the pheromone emissions of a member of the same sex? This would lend credence to one view, which is that homosexuals are born as such.

How come when you are super starved u cannot eat food rapidly? apparently it is bad for you and those problems popped up during wwII with all those starved prisoners.

Can someone please be so kind to answer these three questions? I’d be truly grateful!! 1) Why is the value of the hydrostatic pressure 0 kPa at the heart level instead of being 0 kPa at the top of the head? What are the physiological reasons for that? 2) Why is the venous system so important when talking about the impact of the hydrostatic pressure on the circulation? 3) How does the blood go through the foot capillary system (of a standing person!) if the pressure at the venous end is 12 kPa, and at the arterial end only 4 kPa? Thank you all very very much And, btw, I sincerely apologize for any grammar mistakes made – I’m still studying English. Thanks …

Who thinks that as you get closer to the brain stem, the complexity of function reduces? Feel free to throw in technical words like amygdala and synaptic.

Last night my father and I were coming home from the mall and we turned on NPR (National Public Radio.) There was a really interesting peice on how Dr. Helen Mayberg of Emory University had implanted small wires the size of a human hair into Area 25 of the brain. Apparently the higher the electrical impulse, the happier and more peacful the patient became. One even said that when the procedure was applyed to him, it seemed as if someone had pulled up the shades and everything seemed brighter. One female patient said to have an immense sense of calm and rest and as soon as they lowered the power going into her brain she knew that they had changed something. Now I have…

A long time ago something came up in a conversation with a friend about how long you can see or how long you "live" essentially after you die. My friend said 10 seconds and told me a story or something he heard. It goes like this: Somebody's wondering the same question and says to somebody else, when the guilotine goes down and my head comes off, I will blink for every second I can see/live/whatever, So the guilotine comes down, and his head comes off, and it blinks ten times, one for each second. So I didn't believe him and said it was probably just a muscle spasm or something like a snake's jaws do when it's killed while snapping. Any thoughts? Sorry about how …

am doing an project on the neural map in the brain. i am not sure wot to include in my topic. do i start off writing something about nervous system then move to the brains and the nerves. and by the neural map wot does it relaly mean. does it mean the way all the nerves work . i did a bit of research but wasnt able to find much on the topics. ayone with any knowledge about the topic please help meee....

i have an 30 % assignmet due on "neural map in the human brain." i did a lot of research but am still confused about the topic. there wasnt much about neural maps in the books nor on the net. if ya know anything about the topic pleaseeee help me .. wot do i write about. do i include the part of the brain and thier function and the nerves in the brain that help perform its funtion.. please anyonee helpp me outtt...... pleaseee

Howdy, I am working on a cure for bipolar, schizophrenia, autism, stupidity, stroke, and Alzheimers. I am primarily trying to due research on neurotrophic agents, synaptogenic agents, agents that reverse maturation, and neurogensis in purkinje cells or the adult cerebral cortex. I have 2 out of 6 of those conditions. Anyway, so I spend ALOT of my time doing research and all I want is for the cures to be made. Anyway, You can double check everything I say at pubmed, go to google, pubmedat national institute of health What I have come up with so far is, - That Glial cells inhibit synaptogensis, due to mylenination, the synapses can't easily con…

Does anyone know of a chart that matches mood to the levels of certain neuro-chemicals in the brain. For example, I'm pretty cure (but I could be wrong) that happiness correlates with high levels of seritonin. Does anyone know what neuro-chemicals correlate with moods like depression, anger, love, guilt, fear, etc.? Even a reference to an on-line source would help. Thanks

I was reading a Scientific American magazine yesterday on the brain differences between men and women. One of the differences was in the size of the amlygada, men's are larger than women's. Yet, they said schizophrenics had sizes of the amylgada that were contradictory to most of their findings. So, this made me question if schizophrenia can be acquired or if you are born with it? If it is acquired, does this mean that the sizes of certain areas in the brain can change, whether voluntarily or involuntarily?

correct me if im wrong, but the nervous system uses electrisity to transmit data. your body aslo contains iron - would it not be possible with a strong enough EM feild to simulate the entire nervous system - similar to a taser.

I was wondering why Brain tumors were so deadly. Compared to other tissues, like bowel or skin, neurons are not rapid dividers. Which shoudl allow very tight targetting(and hence highr doses of) the drugs which whack rapidly dividing cells with minimal colateral damage. Yet the figures suggest otherwise? Any ideas why? Cheers.

My question is: It has been said that a teaspoon of either sugar or malt vinegar is supposed to clear the hiccups. From experience I have found that it does seem to work, but what I wanna know is if here is any scientific reason as to why this method might work?

Hey, What happens when adequate ATP is present within the muscle fiber, but action potentials occur at a frequency so great that calcium ions are not transported back into the sarcoplasmic reticulum between individual action potentials? Please help, anything would be helpful. This is for my anatomy class. Peace, Justin

As everyone probably knows, in the human body, the right hemisphere controls the left side, and vice versa. A little while ago I was struck by a question: Why is this the case? Is there some sort of efficiency gain, in spite of what I'd think? Or is it a retained primitive trait? If so, what other groups of animals have this, and why did it occur when it did? Is it the product of some sort of developmental/evolutionary constraint (if so, which), or is it genuinely adaptive? In short, why does this crossover exist? Mokele