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Perception of Body
unable to move one's hands, blink one's eyes, to sit or stand and even to breathe.
It has two divisions: (i) Central Nervous System (CNS) and (ii) Peripheral Nervous System (PNS).
The Central Nervous System is composed of:
(1) The brain, and
(2) the spinal cord.
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They merge smoothly into one another without any obvious demarcation; the portion above the foramen magnum (the opening in the base of the skull) is considered as the brain, while the portion below it is the spinal cord.
The Peripheral Nervous System consists of 12 cranial nerves and 31 spinal nerves which branch and rebranch, after leaving the brain and spinal cord respectively, to form an intricate network throughout the body. The PNS also contains the autonomic nerves which regulate the activities of the internal organs. The action of these nerves is not generally under voluntary control.
More than 10 billion neurons comprise the human nervous system. Through the intricate network run impulses that are the foundations of creative thoughts as well as desires. Innumerable bits of data continually flood the body's sensory organs and pass from the receptors along the peripheral system to the central nervous system. The latter system screens and evaluates the incoming impulses; stores important data for future retrieval; formulates decisions and initiates actions via impulses sent along the peripheral nerves to the muscular system.
Thus the nervous system has two basic functions(i) the detection and processing of information from within and outside the body, and (ii) production and regulation of movement by muscle-action. Some parts of the brain are also responsible for the control of emotions and the storage of information and are also concerned with personality factors and intellect.
The Brain has three major divisions: (i) the fore brain
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