The Human Brain Grace Steiner and Collin Covington 5/6/12

What is the Brain? The brain is a 3 pound, jellylike mass of fat and protein. It is the biggest organ consisting of 100 billion nerve cells. Two- fifths of the brain supports glial cells.

What Does the Brain Do? It controls how you see things, smell things, feel things, and it controls your reactions. It controls all your body’s functions. The right half of your brain controls the left side of your body, and the left side of your brain controls the left side of your body.

How Does the Brain Work? It does this by sending messages through the nerves to the rest of the body. Neurons gather and transmit these messages by electrochemical signals.

Different Neurons Sensory Neurons- carry signals from the outer parts of your body into the CNS (Central Nervous System). Motor Neurons- carry signals from the CNS to the outer parts of your body. (Muscles, skin). Interneurons- connect various neurons within the brain and spinal cord.

How Do Neurons Work? All neurons work together to transmit thoughts and actions throughout your body. Neurons use nerve fibers called dendrites and axons to communicate the signals.

The Brain’s Parts The brains is broken into many parts, including an inner and outer layer.

The Four Lobes. Occipital Lobe- Controls visual process system and reading. It receives and interprets information from the eyes. Frontal Lobe- Controls problem solving, judgment, motor function, reasoning, and expressive language.

The Four Lobes (Cont.) Parietal Lobe- Controls sensation, handwriting, feeling (pressure, touch, and pain), and body position. Temporal Lobe- Interprets sound and language and processes memories.

Cerebellum Coordinates muscle movement. Controls balance. Transmits information to the spinal cord.

Medulla Oblongata and Brain Stem Medulla Oblongata- Controls automatic actions of the heart and lungs. Serves as a relay and grand pathway for millions of sensory and motor nerves. Brain Stem- Carries sensory and motor nerve tracts and houses neurons.

Pons and Midbrain Serve as further relay stations Medulla, Pons, and Midbrain all have three neurons called the reticular formation. They controls sense receptors and consciousness.

Inner Parts of the Forebrain Distinctive groups of clustered cells form special structures deep inside the brain, above the brain stem and around the ventricles.

Two Main Parts Thalamus- large double structure, major sensory coordinator, processes information from eyes, ears, mouth, and skin. Hypothalamus- controls thirst, hunger, sweating, shivering, and other essential processes.

Three Other Parts Basal Ganglia and Crown Thalamus- relay information from cerebral hemispheres to brain stem and cerebellum. Regulate body’s movements. Limbic System- controls emotions, encircles the brain stem.

Outer Areas of the Forebrain Cerebral hemispheres at the front of the forebrain that house 7/10 of the cells of the entire nervous system.

Five Cortexes Cerebral Cortex- Thin outer layer, seat of human intelligence. Primary Cortex- receives signals from the eyes. Motor Cortex- dispatches motor signals.

Five Cortexes (Cont.) Sensory Cortex- receives sensory input from all over the body. Association Cortex- receive sensations associated with conceptual thought.

Prefrontal Areas Control personality and intellect. Left side- speaking and understanding speech. Right side- visual recognition.

Relationship between Brain and Spinal Cord The brain and spinal cord connect to create the CNS. The CNS controls how the functions get through your body and where they go.

Problems with your Brain Your brain is extremely sensitive and delicate. It is surrounded only by skull and three tough membranes called meninges. Hits to the head can cause the brain to shift or tau accumulation. Chronic hits to the brain from sports can lead to permanent brain damage. Deficiencies in kids can persist for years after the brain injury. Chronic hits also can lead to Alzheimer’s disease, CTE, and brain traumas.

Video Check out the video…. Neurons and How They Work

Conclusion The brain makes us human. It gives us the capacity of art, language, moral judgment, and rational thought, It also gives us our personality, memories, and how we sense the world.

Sources Freudenrich, Craig, and Robynne Boyd. “How Your Brain Works.” HowStuffWorks. How Stuff Works, Inc. Web. 02 May “Brain.” National Geographic. National Geographic Society, Web. 29 Apr Walton, Alice G. “Should Helmets Be Required? The Danger of Repetitive Brain Injury” The Atlantic. The Atlantic Monthly Group. Web. 02 May the-danger-of-repetitive-brain-injury/253479/>. Kramer, Ann, ed. The Human Body. 7 th ed. Chicago: World Book, print. The World Book Encyclopedia of Science. "Webma.com: The Best Search Links on the Net." Webma.com: The Best Search Links on the Net. NA MEDIA Service. Web. 06 May Time Life Books. Human Body. Alexandria, VA: Time-Life, Print.