why do we feel pain?

Question

explain in context of pain fibres

Answer 1

1. Your peripheral nerves extend from your spinal cord to your skin, muscles and internal organs. These nerve fibers vary in their size and the rate at which they conduct messages to the brain. The receptors at the ends of these nerves vary as well. Some types of nerve fibers end with receptors that respond to touch, pressure, vibration, cold and warmth. Other types of nerve fibers end with nociceptors which are receptors that detect actual or potential tissue damage.

2. The nerve fibers that transmit pain messages — such as the throbbing pain from that stubbed toe — enter the spinal cord in an area called the dorsal horn. There, they release chemicals (neurotransmitters) that activate other nerve cells in the spinal cord, which process the information and then transmit it up to the brain.

3. When news of your stubbed toe travels up the spinal cord, it arrives at the thalamus — a sorting and switching station located deep inside your brain. The thalamus quickly forwards the message simultaneously to three specialized regions of the brain: the physical sensation region (somatosensory cortex), the emotional feeling region (limbic system) and the thinking region (frontal cortex). Your brain responds to pain by sending messages that moderate the pain in the spinal cord.

Answer 2

Our Body is capable of handling many a illness/disease etc. The pain is a signal given by the brain to make us aware something is wrong. This signal indicates that we have to be careful in that area of pain. The other purpose is that we physically also have to help our body.

e.g if a small piece of wood goes in our fingers and we are not aware, then in a day or 2 a pin comes, indicating a goreigh object is inside, the heat will be higher than the other part of the body, and a pus formation takes place to throw the wood piece out of the finger, if we assist the wood to come out the pain will subside and the relief will be there.

Answer 3

Felix and ecurb mahard got it right, there r people who born with out the feeling of pain,very few but there r,one sat down in a radiator and got his *** burn so bad, other used to jump from high places and end dying, pain let u know when u r damaging ur body.

Answer 4

Never heard: "No pain, no gain"? All those stinking rich guys have very strong pain fibres that pain a lot.

Answer 5

Pain is an unpleasant sensation, ranging in intensity from slight through severe to indescribable. Pain is experienced as having qualities such as sharp, throbbing, dull, nauseating, burning and shooting.

Pain can be experienced in response to both external perceived events, i.e. seeing something, or internal cognitive events, i.e. felt tightness in an amputated limb, and can sometimes follow from nociception (synonyms; nociperception, "physiological pain").

Afferent pain-receptive nerves, those that bring signals to the brain, comprise at least two kinds of fibers - a fast, relatively thick, myelinated "Aδ" fiber that carries messages quickly with intense pain, and a small, unmyelinated, slow "C" fiber that carries the longer-term throbbing and chronic pain. Large-diameter Aβ fibers are nonnociceptive (do not transmit pain stimuli) and inhibit the effects of firing by Aδ and C fibers.

The central nervous system has centers at which pain stimuli can be regulated. Some areas in the dorsal horn of the spinal cord that are involved in receiving pain stimuli from Aδ and C fibers, called laminae, also receive input from Aβ fibers (Kandel et al., 2000). The nonnociceptive fibers indirectly inhibit the effects of the pain fibers, 'closing a gate' to the transmission of their stimuli (Kandel et al., 2000). In other parts of the laminae, pain fibers also inhibit the effects of nonnociceptive fibers, 'opening the gate'.

An inhibitory connection may exist with Aβ and C fibers, which may form a synapse on the same projection neuron. The same neurons may also form synapses with an inhibitory interneuron that also synapses on the projection neuron, reducing the chance that the latter will fire and transmit pain stimuli to the brain. The C fiber's synapse would inhibit the inhibitory interneuron, indirectly increasing the projection neuron's chance of firing. The Aβ fiber, on the otherhand, forms an excitatory connection with the inhibitory interneuron, thus decreasing the projection neuron's chance of firing (like the C fiber, the Aβ fiber also has an excitatory connection on the projection neuron itself). Thus, depending on the relative rates of firing of C and Aβ fibers, the firing of the nonnociceptive fiber may inhibit the firing of the projection neuron and the transmission of pain stimuli (Kandel et al., 2000).

Gate control theory thus explains how stimulus that activates only nonnociceptive nerves (such as rubbing a bumped knee) can inhibit pain. The pain seems to be lessened when the area is rubbed because activation of nonnociceptive fibers inhibits the firing of nociceptive ones in the laminae (Kandel et al., 2000). In transcutaneous electrical stimulation (TENS), nonnociceptive fibers are selectively stimulated with electrodes in order to produce this effect and thereby lessen pain.

One area of the brain involved in reduction of pain sensation is the periaqueductal gray matter that surrounds the third ventricle and the cerebral aqueduct of the ventricular system. Stimulation of this area produces analgesia (but not total numbing) by activating descending pathways that directly and indirectly inhibit nociceptors in the laminae of the spinal cord (Kandel et al., 2000). It also activates opioid receptor-containing parts of the spinal cord.

Afferent pathways interfere with each other constructively, so that the brain can control the degree of pain that is perceived, based on which pain stimuli are to be ignored to pursue potential gains. The brain determines which stimuli are profitable to ignore over time. Thus, the brain controls the perception of pain quite directly, and can be "trained" to turn off forms of pain that are not "useful". This understanding led Melzack to point out that pain is in the brain.

Answer 6

it is because of stimuli.
if we prick our hand using a pin,
the pain fibres located there will send signals to the brain and that is why we are feeling pain.

Answer 7

so that we are kept from hurting ourselves.

I recently heard a news report on BBC which said that some people of Pakistani origin have been found to have no sensation of pain. So, that resulted in them hurting themselves.

hope this helps.

Answer 8

tiny pain recepters are located all over our body, sending signals to the brain at all times. When a pain recepter feels pain, it feeds that information to your brain so you know that you are feeling pain, heat, textures, ect.

Answer 9

We feel paining when we are hurt.Our brain will say ''let there be paining'', because if there is no pain if we are hurt we will not bother about that hurting,but if we have pain we will realise that there is some problem.

Answer 10

You obviously haven't thought this through, if you didn't feel pain you could seriously damage yourself and not know it - you wouldn't live for very long