Nerves

The average human skin contains approximately 5 million touch receptors, including various types such as Meissner's corpuscles, Pacinian corpuscles, and Merkel cells. These receptors are distributed unevenly across the body, with areas like the fingertips and lips having a higher density. This intricate network enables us to perceive a wide range of tactile sensations.

The nervous system uses mainly neuron cells to communicate. The neuron communicated "electrically" through what is called an action potential (basically an electric "signal" that travels along a neuron), this is generated when an appropriate stimulus (on a cellular level) brings the axon hillock region of the neuron to an electrical potential difference (between inside and outside of cell) of -55mV. This triggers the electrically triggered Na+ (sodium ion) gates to open, this causes a massive flow of a + charged ion into a region of the cell, making it more positive there, which triggers another electrically gated Na+ channel right next to it (closer to the "end" of neuron), then the flow of Na+ ions in to that region open the gates next to it....ect. This repeats until the "signal" has traveled all the way down to the "end" of the neuron. The "signal" is really information.

Neurons can use chemicals to communicate too, these chemicals are called neurocrines. They can work like hormones (long distance commun. and travel through the blood stream), or they can work on a very short distance (neurotransmitters). I will give an example using AcH (acetyl choline, a neurotransmitter used in many cases, including muscle contraction). When you think about moving your arm, action potentials are generated in your brain and travel along other neurons (through spinal cord, and through/into arm) and end up right above certain parts of muscle cells. they stop just above but don't touch your muscles. then as the action potential reaches the end of the neuron, the "electrical signal" is converted into a chemical signal (by devices in the neuron looking for specific voltages before "production" begins). Then this chemical (AcH or ACh) is released from the end of the neuron right over the muscle cell (this region is called the synaptic cleft). The AcH travels a very very short distance and then binds to receptors on the muscle cell, stimulating the muscle cell to begin the contraction process, the action potentials are coming one after another as fast as they can (there is a limit). so when you hold you arm out, your muscles not getting a continual signal telling it to stay contracted, but a series of signals, and so in the space between the neuron and muscle cell a chemical is released (by the muscle cell) that's breaks down the AcH in such a way that the muscle cell thinks its getting a continuous signal. I got a little off topic but i wanted to explain why the space was there.

Certain neurons can repair themselves while others can't. Neurons that can repair themselves are refreed to as white matter. The reason white matter can repair itself is because the axons of white matter are myelinated. The axons of neurons in grey matter on the other hand, cannot repair themselves because they are unmyelinated.

Neurons are classified by the direction they move.

Dendrites are the part of the neuron specialized to receive information from other neurons and the axon transmits signals to other neurons or to muscles or glands.

they turn in to light and go through three bones...

Although neurons are very diverse and there are exceptions to nearly every rule, it is convenient to begin with a schematic description of the structure and function of a "typical" neuron. A typical neuron is divided into three parts: the soma or cell body, dendrites, and axon. The soma is usually compact; the axon and dendrites are filaments that extrude from it. Dendrites typically branch profusely, getting thinner with each branching, and extending their farthest branches a few hundred micrometres from the soma. The axon leaves the soma at a swelling called the axon hillock, and can extend for great distances, giving rise to hundreds of branches. Unlike dendrites, an axon usually maintains the same diameter as it extends. The soma may give rise to numerous dendrites, but never to more than one axon. Synaptic signals from other neurons are received by the soma and dendrites; signals to other neurons are transmitted by the axon. A typical synapse, then, is a contact between the axon of one neuron and a dendrite or soma of another. Synaptic signals may be excitatory or inhibitory. If the net excitation received by a neuron over a short period of time is large enough, the neuron generates a brief pulse called an action potential, which originates at the soma and propagates rapidly along the axon, activating synapses onto other neurons as it goes.

source : a fragment of the whole article about neurons from Wikipedia.

The X craneal nerve (vagus), it goes all the way to your diafragm

Atropine and 2pam chloride. This is in a kit that the us military gives out. Not sure of the doses, but I do know that the needles for the injection are HUGE. I know this, because I am currently in the military and this has been something that we are taught from basic training and continuously throughout our careers.

the function of neurons is to receive information, process it, and pass it on to other neurons, or muscles or endocrine/exocrine glands. I realize 'receive information, process it, and pass it on' is a giant and amorphous description, but the description of the behavior of organisms with neurons is also giant and amorphous.

You should always see your doctor with these symptoms. Most of the time it's stress through the neck and shoulder area and when under stress the muscles freeze up (like a knot.) A good soak in the tub with Epsom Salts will certainly help, and rub your neck and shoulders well with A535. If you are still having this problem then please see your doctor immediately.

If the pins and needles go along with a heavy chest or jaw pain call 911! It may be due to anxiety due to stress (many patients think they are having a heart attack and it turns out to be anxiety.) It's better to be safe than sorry.

NumbnessNumbness and tingling and parasthesia on the left side of the body means that there may be an abnormality in the right side of the brain.It can be a neurological pathology like motor neuron disease,TIA or stroke or autoimmune condition like multiple sclerosis in which the immune system attacks the central nervous system (CNS), leading to demyelination.It can be diagnosed by MRI brain and MRS of the brain.

Other possibilities are vit B12 deficiency,diabetes, hypothyroidism, hypoparathyroidism or peripheral nerve trauma or compression.

If tingling is there only on the left half of the body,it means a right side pathology of the brain.So I feel that clinical evaluation from a neurologist is necessary to rule it out.

No. People cannot live without the brain, because the brain controls your body.

You won't be able to breath, move, eat or do ANYTHING, not even swallow, you would be useless without a brain.

Neurons send messages electrochemically and all chemicals in the body are electrically-charged. When neurons inside the body are electrically-charged, they are called ions. When a neuron is at rest, or not electrically-charged, the inside is negative and the outside is positive.

The nerves innervate the quadriceps. The afferent nerves are the muscle spindles and the efferent are the motor neurons.

d test for pinched nerve not pinched finger numb

Skeletal muscle:

(occurs at neuro muscular junction)

At the end of the skeletal muscle fibre, there is a single motor neuron that forms many finer branches. At the end of these branches is a synaptic terminal which contain mitochondria and vesicles which in turn contain ACh.

So, when an action potential is propagated down towards the synaptic terminal, ACh is triggered to be released by exocytosis into the synaptic cleft and then onto the motor end plate (which is the other surface upon which the action potential will propagate; this is highly folded for increased surface area).

ACh then binds to receptors on the motor end plate, changing its permeability to Na+ ions. Na+ ions (due to an increased electrochemical gradient) rush into the sarcolemma. This influx increases until AChE breaks down the ACh. This influx results in the generation of an action potential!

The nerves that controls your facial movements exits the skull from behind, below, and deep to your ears and come toward the middle from both sides to converge upon the nose. BEFORE the nerve leaves the skull, a branch of the nerve crosses below the brain across the skull base to enter the nasal cavity. This branch, however, has nothing to do with facial motion rather it helps control the mucous glands in the nasal cavity and palate. Most problems with facial paralysis result from 1) stroke 2) ear pathology (infections, tumors, etc) and 3) parotid gland (in front of the ears) pathology which damage the origin of the nerve in the brain or the nerve itself.

Scientists.

It could be poor circulation, or even early signs of carpal tunnel syndrome.

The Synapse is the area between an axon and a dendrite

The most immediate effect would be an increase in heart rate. In addition, regulation of heart rate, contractile state, and conduction of electrical impulses through the heart would be impaired.

The reason for the observed effects are that the vagus nerve carries important information to the heart from a part of the central nervous system called the parasympathetic nervous system. The parasympathetic nervous system is often considered the "rest and digest" system. It decreases heart rate, decreases how strongly the heart contracts with each beat, and decreases the rate at which electrical impulses are conducted through the heart. This is in contrast to the effects of the sympathetic nervous system on the heart; the sympathetic nervous system raises heart rate, force of contraction, and rate of electrical conduction in the heart.

A normal heart does not require information from the parasympathetic and sympathetic nervous systems in order to beat. The heart has an intrinsic pacemaker that allows it to generate heart beats on its own. The heart's pacemaker generates a pace at a rate of about 100 cycles per second, which means that if the heart was to take matters into its own hands (ie, have no innervation), then it would beat at about 100 beats per minute (bpm).

If that's the case, then why do normal adult hearts beat around 70 beats per minute and not 100?

As was hinted at above, normal hearts are innervated by the parasympathetic and sympathetic nervous systems. And both act on the heart at the same time. While you might think that the systems would cancel each other out, it turns out that the heart receives more sympathetic stimulation than parasympathetic stimulation at rest. The result is that the heart is effectively told to reduce the heart rate from the normal 100 bpm to something closer to 70 bpm.

Thus if you take a normal heart at rest that's innervated by both sympathetic and parasympathetic systems, and then sever the vagus nerve, you lose the parasympathetic input to the heart, while leaving the sympathetic input intact. The result is that the resting heart rate increases, to something closer to 100 bpm. ________________________________________________________________________ Cutting the vagus nerve would increase the heart rate. At REST there is more Parasympathetic input to the heart because it slows the heart rate. However during activity there is more sympathetic imput than parasympathetic imput. If all nerves were cut from the heart it would continue to beat in a Ryhmic way because of the electrical system, as demonstrated in heart transplants.

optic nerve