What speed do nerve impulses travel and more....
Fascinating facts about the nervous system
The nervous system is made up of the CNS and the PNS
The CNS or central nervous system is made up of the brain and spinal cord. The PNS or peripheral nervous system is made up of the cranial nerves arising in the brain, and spinal nerves arising from the spinal cord.
The CNS is connected to sensory receptors (sight, smell, touch, pain) / muscle and glands in the peripheral part of the body by the PNS.
The two systems communicate by sending messages along the neurones - think of a cell with lots of tentacles coming off it like the legs of an octopus (dendrites) and one very long tentacle (axon). These axons connect to other neurones at junctions called synapses. Some neurons have axons which are surrounded by a myelin sheath which increases the speed at which the impulse travels.
Nerve impulses are speedy.....
Nerve impulses travel at speeds ranging from 1-370 miles an hour!
There are 100 billion neurons in the human brain with up to 10, 000 connections......that's about 500, 000 times as many connections as the most advanced computer chip!
How does the brain decide which impulses to act on...........
Obviously with all these neurones transmitting information at once, your body needs to filter and process them. Imagine the confusion of information we'd feel if it wasn't......'bottom cheek feeling squished', 'right foot needs to move', 'need to alter the pressure on the pen', 'need to blink', 'bladder half full' etc etc all at the same time!!
In simple terms what happens is that information comes from the peripheral nervous system into the spinal cord, where it is sent up to the brain for processing, interpretation and integration to see if a response is needed in either a voluntary or involuntary way. For instance, the 'full bladder' signal has to be processed appropriately in the context of the environment - when we get that signal, we don't act like a dog and pee against a lamppost immediately, we hold on until a socially acceptable time to go to the toilet!
So how do we feel pain and is it useful?
Recent evidence has changed the way we think about pain. Previously it was seen as an input from the peripheral nervous system, but more recently it has been thought of as an output of the brain. The information comes in to the brain from the PNS via the spinal cord, as described above, and then the brain processes it in relation to your environment, previous experiences, thoughts and feelings, and acts accordingly. In the case of a twisted ankle, the brain is made aware of danger to the tissues, and makes it hurt accordingly. You therefore take the weight off it and rest the tissues temporarily allowing them to heal.
What is harder to explain is why some people get pain, after the tissue damage has healed. I have attached some links below which explain in greater depth why this can occur and what can be done about it.
At Cathedral Physiotherapy we pride ourselves on being able to alter our approach to treatment to incorporate all areas which may be impacting on your pain.