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The mouth and face are the location for 30-40 per cent of the body's sensory and motor nerves.This is sensation from the various viscera (internal organs) or organs of the body, as well as from the mucous membrane from the tonsils on down through the digestive and respiratory tract.The brain coordinates and sends out messages that cause muscles to contract, stimulates glands to secrete, regulates numerous functions, and performs many of these tasks without true consciousness on our part.The somatic nervous system consists of peripheral nerve fibers that pick up sensory information or sensations from the peripheral or distant organs (those away from the brain like limbs) and carry them to the central nervous system.When you feel stressed, the sympathetic nervous system, or 'fight or flight' response kicks in. At this point, the sympathetic nervous system becomes dominant and diverts blood from the digestive system to your leg muscles, enabling you to run from danger.The second category of the nervous system is the voluntary or peripheral nervous system, which comprises all nerves that extend outward from the brain, spinal cord.The system has motor and sensory fibers; the motor fibers supply smooth and cardiac muscle and glands, and the sensory fibers carry what is called visceral sensation.A motor message then left the brain and travelled down the spinal cord, and a second motor neuron carried the message out of the spinal cord and along a peripheral nerve to muscles that pulled the finger out of the drawer.The peripheral nervous system is made up of sensory neurons, ganglia which are groups of neurons, and nerves connecting to other nerves and the central nervous system.These also consist of motor nerve fibers that come out of the brain and take the messages for movement and necessary action to the skeletal muscles.These axons cause chemicals or neurotransmitters to be released at a synapse or junction.For example, on touching a hot object, the sensory nerves carry information about the heat to the brain, which in turn, via the motor nerves, tells the muscles of the hand to withdraw it immediately.The neuron's cell body that carries the information often lies within the brain or spinal cord and projects directly to a skeletal muscle.The autonomic nervous system is further divided into parasympathetic and sympathetic functions.When you feel relaxed, the parasympathetic nervous system is dominant and allows your body to function optimally.Neurons are bundles of fibers.The fibres are called axons.It has both.

The mouth and face are the location for 30-40 per cent of the body’s sensory and motor nerves. It’s the most sensitive part of the body. The nervous system is a key mediator of health and wellbeing. The nervous system is made up of special cells called neurons and a network of nerves. They transmit messages all over the body. Neurons are bundles of fibers. They branch out to every part of the body from the brain and the spinal cord. The fibres are called axons. These axons cause chemicals or neurotransmitters to be released at a synapse or junction. The nervous system has many routine functions. It relays messages from distant parts of the body that let the brain know exactly what is happening in each part. The brain may file the information in its memory for future reference, or it may react immediately to that message. The brain coordinates and sends out messages that cause muscles to contract, stimulates glands to secrete, regulates numerous functions, and performs many of these tasks without true consciousness on our part. To accomplish all this, the nervous system has to have tremendous organization and potential. It has both. Some authorities have theorized that we normally use only 10% of our mental capacity. There are clearly more cells in the brain than we could ever use, and sometimes when there is brain damage, these unused cells can be called upon to re- establish damaged pathways.
The nervous system is divided into two major categories. The first category is the involuntary or central nervous system. The central nervous system consists of the brain, spinal cord and nerves. The brain and spinal cord are made up of neurons that are either motor or sensory, but they are only part of the chain. Imagine that you have caught your finger in a desk drawer. You feel pain and quickly pull your finger out of the drawer. Neurologically, a pain receptor or free nerve ending in
the finger has picked up the message and carried it to the spinal cord. A second neuron has carried the message up the spinal cord to the lower
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parts of the brain, and a third neuron has taken it to the surface of the brain, where it was recognized as pain. The pain was interpreted by the brain, and previous experience told the brain to remove the finger from the drawer so that it would no longer be crushed. A motor message then left the brain and travelled down the spinal cord, and a second motor neuron carried the message out of the spinal cord and along a peripheral nerve to muscles that pulled the finger out of the drawer.
The second category of the nervous system is the voluntary or peripheral nervous system, which comprises all nerves that extend outward from the brain, spinal cord. The peripheral nervous system is made up of sensory neurons, ganglia which are groups of neurons, and nerves connecting to other nerves and the central nervous system. The Peripheral nervous system is made up of two parts: Somatic nervous system &Autonomic nervous system. The somatic nervous system consists of peripheral nerve fibers that pick up sensory information or sensations from the peripheral or distant organs (those away from the brain like limbs) and carry them to the central nervous system. These also consist of motor nerve fibers that come out of the brain and take the messages for movement and necessary action to the skeletal muscles. For example, on touching a hot object, the sensory nerves carry information about the heat to the brain, which in turn, via the motor nerves, tells the muscles of the hand to withdraw it immediately. The whole process takes less than a second to happen. The neuron's cell body that carries the information often lies within the brain or spinal cord and projects directly to a skeletal muscle.
The autonomic nervous system is also called the automatic nervous system because it is not willfully controlled. The system has motor and sensory fibers; the motor fibers supply smooth and cardiac muscle and glands, and the sensory fibers carry what is called visceral sensation. This is sensation from the various viscera (internal organs) or organs of the body, as well as from the mucous membrane from the tonsils on down through the digestive and respiratory tract. The autonomic nervous system is further divided into parasympathetic and sympathetic functions. When you feel relaxed, the parasympathetic nervous system is dominant and allows your body to function optimally.
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It helps to digest food, a regular heart beat and allows your
immune system to work optimally – ‘rest and digest’.
When you feel stressed, the sympathetic nervous system, or ‘fight or flight’ response kicks in. At this point, the sympathetic nervous system becomes dominant and diverts blood from the digestive system to your leg muscles, enabling you to run from danger. But these days, danger isn’t from a saber-toothed tiger coming after you but the experience of being cut off in traffic or from other emotional stresses.