PNS
THE PERIPHERAL NERVOUS SYSTEM (PNS)
This system consists of nerves, some of which gather information while others transmit orders. The facial nerves enter and leave the brain directly through the skull. The rest reach the brain via the spinal cord and the atlas.
The PNS is divided into 3 sub-systems:
The SOMATIC NERVOUS SYSTEM (SNS). These nerves participate in the organism’s relationship with its external environment. They send information to the brain from the body’s various sensory detectors. They also enable us to respond to these stimuli by consciously controlling the movements of our body from our head-brain systems.
The ENTERIC NERVOUS SYSTEM (ENS). The ENS is involved with food digestion and waste elimination. However, 90% of its nerve fibers run up, from the stomach area, through the vagus nerve into the brain.
Over 90% of our thoughts occur in our subconscious mind, the home of our ENS, who produces 90% of our serotonin.
While the cerebrospinal system or CNS is the organ of the conscious mind, and has the head-brain as its control center, the ENS has a ganglionic mass in the belly known as the Solar Plexus, the gut-brain, as its central processing unit.
This coprocessor executes most of our everyday tasks. When things in our life become ‘second nature’, they are effectively processed through our ENS rather than our CNS.
The AUTONOMIC NERVOUS SYSTEM (ANS). This system (old name: vegetative nervous sytem) is controlled mainly by the hypothalamus and can only be controlled by the human will after special training. It is divided into 2 nervous systems:
The Sympathetic and Para-sympathetic Nervous Systems.
Each has its own anatomy and communicates with its target organs through its own neurons located in ganglia of our gut-brain, called Solar Plexus. These nerves regulate vital internal functions, over which we have no conscious control.
This subconscious mindset helps maintain internal equilibrium by coordinating such activities as digestion, respiration, blood circulation, excretion, and hormones secretion.
The interaction of conscious and subconscious mind requires a similar interaction between the corresponding systems of nerves. One conspicuous connection by which this is provided is the vagus nerve.
This nerve comes out of the cerebral region as a portion of the voluntary somatic nervous system, and through it we control the vocal organs. Then it passes the thorax and sends out branches to the heart and lungs.
While passing through the diaphragm, it loses its outer coating which contain the nerves of the voluntary system. The inner lining now connects itself with the sympathetic system, and forms a unifying link between the SNS & ANS.