How the Nervous System Works

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Did you know that there are more nerve cells in the human brain than there are stars in the Milky Way? The Nervous System is one of the most important systems in the human body. Without the Nervous System, no other systems would be able to function in the body. Our Nervous System helps us to fell pain, move, and it also tells the other systems in the body what to do. The Nervous System is the network of nerve cells and fibers that transmits nerve impulses throughout the body. It consists of two main parts, the central nervous system, or the CNS, and the peripheral nervous system, or PNS. The central nervous system is made up of the spinal cord and the brain. The job of the CNS is to receive information from various parts of the body, analyze and store the information, and then send out instructions based on the information it has received. The peripheral nervous system is composed mainly of nerves and neurons. The PNS connects the central nervous system to limbs and organs of the body. However, unlike the central nervous system, the peripheral nervous system is not protected by bone or the blood-brain barrier, making it easy for it to be exposed to toxins and injuries. The central nervous system contains the brain, which is the control center of the body. In the brain there are three main constituents: the forebrain, the brainstem, and the hindbrain. The forebrain receives and processes sensory information and controls motor function. The thalamus and hypothalamus are responsible for motor control, relaying sensory information, and controlling autonomic functions. The forebrain also contains the cerebrum, the largest part of the brain. Majority of the information processing in the brain occurs in the cerebral cortex. The brains... ... middle of paper ... ...together very simply. Sensory nerve fibers respond to different things and produce chemical responses. These chemical responses determine how the sensations are interoperated. Once these sensations are interpreted, an impulse travels through the nerve into the spinal cord and reaches the brain, all within fractions of a second. Once the brain receives the message, it sends a message back down through the spine and to the nerves. Sometimes, a signal will not have to travel all the way to the brain before a decision is made. These happen in the dorsal horn, which is a section of the spine that acts as an information hub. When the dorsal horn makes a decision before the brain does, these are called “reflexes”. However, once the dorsal horn sends a signal, the original information still travels to the brain so that it can be stored and processed to a greater extent.
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