Anatomy, Physiology and Neuroscience

I have a few questions on EMGs- we did two tests in class, one one biceps flexion, and the other on tricep extension. 1) I still don't understand what an EMG is measuring - is it Action potential frequency?, size of action potential (action potentials aren't the same size, so it probably isn't this). 2) Why does an EMG have both a positive and negative y-axis if it supposed to be measuring depolarization? 3) What do the spikes on an EMG represent http://www.unmc.edu/physiology/Mann/pix_14/emg.gif 4) What does a cluster of spikes represent? Thanks, help is greatly appreciated

Some medical schools ask in exams like this, given a bone(femur/humerus/etc), identify if it is on the right bone or left bone. I'm wondering what are techniques or perhaps ways to determine the bone and kindly let's discuss in here. Whose anatomy books should i read? please state author. I'm currently taking Physical Therapy and anatomy 1.

Hello everyone, First of all I have not seen a paranasal sinus for real, so I'm bit confused how it looks like. For example the maxillary sinus. So to see it you have to cut half of maxilla from front right. Then it is covered by mucous membrane, is this mucos membrane on top of bone. What I'm asking is do you have cut the maxilla from behind as well to see the sinus, or only from the front. Thank you I also don't understand the function of these sinuses. How do they reduce the weight of the front of the skull (the air filled cavities reduce weight is that it,rather than having bone). Also more importantly how do they resonate voice. When you speak how …

Hi. The thermal emission from our bodies at about 37°C warms up the air next to the skin. What happens when the ambient temperature is like 40°C and beyond as in some regions ? Does the body 'mechanism' go into cooling or into stop heating ? Where is the excess heat 'dumped to' ? Would the air layer next to the skin be cooler than the ambient ?

Hi everyone, I wanted to share with you an exciting new education portal for Neurology I found to be really helpful - CCO Neurology - that recently launched with independent conference coverage of the 2010 Meeting of the AAN. The portal has expert highlights of data presented in epilepsy, Parkinson's disease, and restless legs syndrome. You can register and review available coverage here: http://www.clinicaloptions.com/Neurology/Conference%20Coverage/Toronto%202010.aspx. They have updates when new activities become available on the CCO Neurology Facebook page- http://www.facebook.com/pages/CCO-Neurology/109048042459232#!/pages/CCO-Neurology/109048042459232 as …

I would be interested on anyones opinion or guidance on the following: I have created a device that is connected to the ear. As a side effect of its design, the device creates nitrogen dioxide (NO2, and probably NO/NO3 so NOx). The NOx is not emitted into the atmosphere to be breathed it is trapped in a capsule sealed by the ear and exposes the outer ear to what would be considered fairly high concentrations (>200ppm) of the gas. The device may be used for several hours at a time. I have attempted as much research as I can to find any scientific tests or papers on the affect of NOx on the skin or ear. Of course there are many on the affects on the lungs and…

If I could make an immortal mouse, would that be proof in concept that I could do it with a human? Let us assume that I'm opening up mice, putting in robot limbs, inserting stem cells, and playing doctor with them. Yes, I know, quite serious stuff. If I could make that mouse live as long as I desired (which means I had to actively open it up and alter its anatomy/physiology) would that be proof of concept that I could do the same with a human?

My definition/understanding- Do you agree? Acyclic- Mind/mental leadership of movement. Locomotion concerned with doing the right technique unnaturally ( with practice, objects, vision, empowerment, concentration) Cyclic-Mind/Mental management of movement. Locomotion concerned with doing techniques right naturally ( with nurturing, objects, vision, empowerment, concentration) Combined Acyclic- Listening and learning from undulated locomotion.

Hi, I am a competetor and instructor of motorsport. I try to live up to the name motor-sport and teach my drivers not to underestimate the physical skill nessecary in terms of correct body positioning, utilization of vision, etcetra. As an instructor, I have two issues in need of solving: 1. Regarding our seating position: Some instructors teach their students to seat with the shoulders on the seat and the palms on the wheel in parallel heights. Others, such as me, teach a position where the palms are slightly lower than the shoulders, approximatly 5cm. I have heared it has to do with blood circulation, but without detail or proof. What to do and how? 2. Regarding…

I already know that preventing inactivation of some neurotransmitter can kill the post synaptic neuron ...but i m wondering did when Prozac is preventing inactivation of that neurotransmitter can lead to dead of some neuron ?

It seems very unusual to see people in their seventies and beyond being obese. Is it because at a certain age something reverses and shrinkage and weight loss takes over ? Or because all the obese already died never making it to that age ? Do you know elders who were obese at certain point in their lives and 'naturally' greatly lost the overweight ?

hello guys, can someone plz explain to me what happens in a single muscle twitch and to be specific i wanna know how is it possible according to this diagramm that the myocyte keep contracting and reaches its Maximum contraction power after the calcium concentration drops???? and one more thing : superposition of 2 single twitches means more calcium concentration and thus more contraction power?? i would really appreciate it ur help guys :doh: thx

When I use my brush my mortars using my electric toothbrush and watch the clock of my microwave oven, it vividly vibrates due to the vibrations of my skull, yet when I turn off the light and look at the light of my printer, it's perfectly still, even though the surroundings appear totally dark. Why does my brain react differently to the numbers of the clock than to the light of my printer? Why do only the numbers vibrate, and everything else in the environment, even if isolated in darkness, appear still? Is this an optic effect, caused by a possible lower frequency in the light of the clock, or some kind of neurological or other effect, perhaps caused because my brain int…

My question stems from a previous question that i had about how the light signal is interpreted by the brain through the optic nerve. How does the Brain process sound? is it in a similar fashion that the optic nerve is? that is does a nerve bundle or thread correspond to a frequency/color?

Sup everybody, just registered here, I'm just interested in this topic and would like to research it a little bit. I wasn't sure if I should put this in Neuroscience or Psychology, perhaps it can be both depending on the specific situation. I've caught people self talking before (at work haha) and also I do self talk every now and then, a lot of other people admitted they do it, including my doctor. A lot of articles put self talking into a positive perspective, and I'm always cautious when things get put into the positive for the sake of being positive. The main idea is that self talking organizes the mind and the thoughts, and that the majority of self tal…

Is there anyone out there with at least some experience in this topic? I'm hoping to develop a microscopic method (darkfield or brightfield) for disease identification using light sources from UV to IR to laser and everything in between - as opposed to using e.g., Wright's & other stains, etc. My initial research indicated that there may be some value in LBA form of diagnostics, which (to my mind) may still be in a rather underveloped stage, and sometimes used unjudiciously. Appologies for stepping on some sensitive toes! Thx

Hey everyone, I had a question about the a part of the endocrine system, particularly the hormones called the chatecholamines. If the chatecholamines (epinephrine, norepinehprine and dopamine) are synthesized by modifying tyrosine, would a person with a metabolic disorder like albinoism (a tyrosinase deficiency)have a reduced fight-or-flight response when put in a stressful situation? I know that tyrosinase is an enzyme (otherwise, it wouldn't have the suffix -ase), but would that have any effect on the sympathetic nervous system? Thanks

how is the pituitary gland (which is part of the endocrine system) linked to the kidneys (which are part of the renal system)?

As a keen drinker of a certain diet drink - lets call it 'Diet Cole', I was slightly concerned about the effects of the sweetener Aspartame in the drink. Britain seems to welcome the presence of aspartame in drinks here. However, a chance look at a health website came up with some frightening side effects. Are these dosage-dependent? And would they affect someone who drinks two cans of this drink a day? Effects: And even more bizarrely -

Hello guys, I don't know much about brain and stuff I only know a bit about action potential. My question is I can understand how sensory nerves by a stimulus, but let's say I want to pick a pen. How does brain initiate the action potential for that? This might have been dicussed before but I'm not sure what to type in google to find the answer. Thanks

is it possible to go through out the whole day slowly drinking in your caloric intake and getting all of the nutrients you need? I was thinking about making a powder of some sort that is low in everything, added to water, and you mix a amount that is proportional to what you would be eating in that particular time of the day. eventually by the end of the day you could consume the right amount of nutrition to maintain your caloric needs, and by constantly consuming the low everything powder (mixed in water) it could maintain a high metabolism. would such a thing be healthy?

Hello everyone:) I am not sure if anyone can help me, but I have a few questions that I thought I would throw out there since I have pretty much reached a dead end in my own research. My little sister has recently been diagnosed with Stage 4 Lupus. Don't ask me how it got as far as it did without being diagnosed. She simply slipped through the cracks of the medical system and was misdiagnosed for many years until I was browsing the internet one day and found the connection between Reynaud’s Syndrome (which she has had since she was a young child) and Lupus. After consulting her doctor on this he ran some tests and found that she indeed has Lupus and it was in a…

I'm supposed to know what happens in the body when you inhale oxygen, and then exhale, in both Aerobic and Anaerobic states. To be more specific, i need to know: -Intaking oxygen through the mouth, and where it travels. -Pathways to the cell body -What happens when oxygen in the cell body -it's affect on energy production -Waste products -How the body rids itself of the waste products. And just generally where exactly the oxygen goes through the body, what muscles contract ect... while you inhale, and then when you exhale. If anyone can take me through what happens in this process, it would be GREATLY appreciated, and i would even be willing to pay…

I'm reading an article, I don't know if some of you can get access to it, but I'd like to know what some of the scientists here think about it. Personally, I think the results are bogus and insignificant. I think over the 8 weeks that people just got better at doing certain tasks, because people get better over time at doing certain tasks. The brain starts forming to do those things better. If I'm understanding the statistics right, there isn't a large difference between the placebo group and the treatment group. There was an enhanced self-confidence effect from the insulin, though. I'm not sure what psychological consequences that would lead to, though. I haven't the…

I just need some confirmations from you guys. Let's say some one take Na+ of 1 mol per day for a week. Will the tonicity of the urine compared to the plasma matter? Or is it still possible that while maintaining the osmotic balance of the body, the urine can be either hypotonic, isotonic or hypertonic? I think that the tonicity of the urine will highly dependant on the water needs of the body, not the concentration of stuffs needed to be excreted. However, I'm unsure since Na+ is also osmotically active, the ions might hold water from being reabsorbed, making the urine more isotonic or hypotonic. This I believe, means that hypertonic (in comparison to plas…