Nervous System

The central nervous system controls the functions within the body and mind. It is made up of the brain and the spinal cord. The brain receives information directly from your ears, eyes, nose and mouth, and communicates with the body through the spinal cord and the nerves. It uses the information received to help you respond, remember, think and plan, and then sends out the appropriate instructions to your body. The brain also interprets the body’s environmental surroundings. Body movement originates from within the brain, even subconscious body movement such as breathing, digesting food, and the beating of your heart. Your spinal cord receives information through the skin, joints and muscles of your body. It also carries the nerves that control all your movements.

The peripheral nervous system has two main components: the somatic nervous system and the autonomic nervous system. The somatic nervous system is responsible for the transmission of sensory information to the central nervous system, and the connection of motor nerve fibers that connect to the skeletal muscles. The autonomic nervous system is further divided in to three parts: the sympathetic nervous system, the parasympathetic nervous system, and the enteric nervous system. The job of the autonomic nervous system is to control the work of our internal organs such as the heart, stomach, and intestines. Most functions of the autonomic nervous system carry out their functions without any conscious awareness. This part of the peripheral nervous system is most important in two situations: the recognition of an immediate threat or danger to our body, commonly referred to as the fight or flight reaction, and in routine bodily functions such as sleeping and digestive activity. The autonomic nervous system regulates muscles in the skin, muscles around the blood vessels, controls the Iris, controls the operation of the stomach, intestines, and bladder, and is responsible for regulating the beating of the heart. The autonomic nervous system also regulates glands such as the adrenal glands.

The heat from running barefoot over hot coals would cause damage to the skin which is registered by microscopic pain receptors known as nociceptors. These pain receptors eventually connect to the spinal cord through an axon which is a long nerve fiber. An electrical signal is then sent over by way of the axon which eventually reaches the spinal column. Once it reaches the spinal column this electrical signal is transmitted from one neuron to another by means of neurotransmitters. Neurotransmitters are chemical signals that travel up the spinal cord to the brain. The brain then determines in the thalamus, also known as the sorting station of the brain what other section of the brain this signal should be sent to. Pain signals are sent to the somatosensory cortex, the frontal cortex, and the limbic system. The somatosensory sensory cortex is the part of the brain that makes you aware of a physical sensation. The frontal cortex is the part of the brain that is used for thinking and reasoning. The limbic system is responsible for emotions. As a result of this situation you would have an emotional response such as feeling annoyed or irritated, and you would have an involuntary muscle reaction causing you to move away from the object that was creating the pain. This involuntary muscle reaction would occur before you were even aware that you are in pain, which is part of the peripheral nervous system which protects the body by the operation of the autonomic nervous system.

Information travels from the brain to the fingers by travelling from the brain to the spinal cord through neurons. The type of neuron that would transmit the signal to your finger is called a motor neuron. Depending on what you wanted to do with the finger and which hand the finger is located on would determine where exactly in the brain the signal would originate.

A traumatic brain injury (TBI) can cause many difficulties! My nephew had a car wreck on his 13th birthday in 2004 which resulted in a traumatic brain injury. This injury caused him to have a massive stroke, which caused fluid build up and swelling on his brain. He was in a coma for two weeks. The brain injury occurred on the right side of his brain. His TBI was an open traumatic brain injury where he actually lost 20 percent of his frontal lobe area of his brain. This caused permanent loss of his peripheral vision in both eyes. He was paralyzed on the left side of his body and could not walk for months. Although he regained the ability to walk, he is still paralyzed in his left arm and hand, and walks with a limp.

 

References:

Chudler, E. (n.d.). Neuroscience for kids – explore the nervous system. Retrieved from http://faculty.washington.edu/chudler/nsdivide.html

Brain and nervous system. (n.d.). Retrieved from http://kidshealth.org/PageManager.jsp?lic=1&ps=207&cat_id=20121&article_set=46284

What is the central nervous system?. (n.d.). Retrieved from http://www.christopherreeve.org/site/c.ddJFKRNoFiG/b.4452157/k.3E9D/What_is_the_Central_Nervous_System.htm

Pain and how you sense it. (n.d.). Retrieved from www.mydr.com/au/pain/pain-and-how-you-sense-it

 

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