Andrea N. Bailey
Overview of the brain and how it works
The brain has many different parts that work together. The brain gets the messages from the senses - seeing, hearing, tasting, smelling, touching and moving. The messages travel from nerve cells all over the body. They travel along nerve fibers to groups of nerve cells, called grey matter, in the brain.
There are five parts of the brain which are key players to the function of the brain and the body.
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1.
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Cerebrum
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2.
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Cerebellum
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3.
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Brain Stem
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4.
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Pituitary Gland
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5.
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Hypothalamus
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The Biggest Part: The Cerebrum
The biggest part of the brain is the cerebrum. This part of the brain makes up about 85% of the brain's weight (Kid Health, 2007). The external part of the cerebrum, called the cortex is the site of reasoning and higher order thought processes. It also controls the voluntary muscles permitting coordinated movement. The cerebrum is required for many everyday functions such as solving math problems, figuring out video games and kicking a soccer ball. Both long and short term memory use the cerebrum.
The cerebrum has two halves or hemispheres, one on either side of the head. The right side of the brain controls movement on the left side of the body and the left side of the brain controls movement on the right side of the body.
The Cerebellum
The cerebellum is located at the back of the brain, below the cerebrum. It's smaller than the cerebrum at only 1/8 of its size. The cerebellum controls balance, movement, and coordination.
Brain Stem
The brain stem sits beneath the cerebrum and in front of the cerebellum. It connects the brain to the spinal cord, which supplies the body. The brain stem controls many of the functions the body needs to stay alive (breathing, digesting and blood circulation).
The brain stem plays a role in control of involuntary muscles. These muscles include the heart, the muscles of the digestive tract and blood vessels. The brain stem tells the heart to pump more blood when playing sports. The brainstem also controls many functions of the head and neck, including moving the face and eyes and chewing and swallowing. The brain stem transmits all the messages to and from the body and the brain.
Pituitary Gland
The pituitary gland is very small about the size of a pea. The pituitary gland produces and releases hormones into the body. This little gland plays a large role with hormones; it controls the amount of sugars and water in your body. It also helps regulate metabolism. Metabolism is everything that is happening in your body to keep it alive and growing and energized. The Webster definition of metabolism is "a chemical changes in living cells by which energy is provided for vital processes and activities and new material is assimilated" (http://www.merriam-webster.com/medical/metabolism).
Hypothalamus
The hypothalamus is the brain's thermostat (Kid's Health, 2007). The hypothalamus regulates body temperature at about 98.6 degrees Fahrenheit (37 degrees Celsius). If body temperature is too high the hypothalamus activates sweating. If body temperature is too cold the hypothalamus activates shivering. The hypothalamus also controls hunger and satiety as well as influencing the pituitary gland.
Spinal Cord
The spinal cord, which is a long bundle of axons and column of neurons inside the spinal column, is made up of millions of neurons. The spinal cord is the information highway connecting the brain and body. The spinal cord in humans is protected by the spinal column. The spinal column is made up of bones called vertebrae. Although, the spinal
column is somewhat flexible, some of the vertebrae in the lower parts of the spinal column become fused.
Neuron
Neurons are highly specialized nerve cells that are responsible for communicating information in both chemical and electrical forms. There are many different types of neurons responsible for different tasks in the human body.
Sensory neurons pass on information from the sensory receptor cells throughout the body to the brain. Motor neurons pass on information from the brain to the muscles of the body. Interneurons are responsible for passing on information between different neurons in the body. Each neuron has an axon (usually one). The axon (a fiber) allows for impulses to be sent outward. Each neuron also has many dendrites which are small short, hair-like fibers that receive impulses from neurons. Dendrites bring information to the cell's body.
Each tiny neuron has tiny branches which connect to many other neurons. According to many scientists when babies are born their brains have with all the neurons they will ever have, although, many of them are not connected to each other (Kids Health, 2007). Messages that are learned go through from one neuron to another, over and over again. The brain begins to create stronger and more connections (or pathways) between the neurons. These connections allow memories to form and learning to occur.
