Anatomy/Nervous System

The nervous system is a topic of the event Anatomy. The nervous system consists of your brain and all the nerves throughout your body. It is responsible for regulating the body's response to external and internal stimuli. It can be divided into the central and peripheral nervous systems. The sympathetic nervous system consists of the brain, retina, and spinal cord; the parasympathetic, sensory neurons and the enteric nervous system (which controls the digestive system).

The Brain
Your brain is arguably the most important organ in your body. It controls all actions, stores memory, and processes the 5 senses. It has many important parts, each with a unique and vital role.



The brain is divided into different lobes: the frontal lobe, the parietal lobe, the occipital lobe, and the temporal lobe. Each has a specific function. The frontal lobe is responsible for conscious thought; damage can result in severe personality changes. The parietal lobe is associated with visual and spatial processing. The occipital lobe controls sight; the temporal lobe processes smells and sounds.

Link: http://webspace.ship.edu/cgboer/genpsycerebrum.html
 * The Cerebrum- The Cerebrum controls perception, imagination, thought, judgement, and decision. The Cerebrum basically consists of the outer surface of the brain. It is further divided into lobes, such as the occipital lobe (processes vision) and the frontal lobe (processes voluntary movement and planning).

Link: http://www.neuroskills.com/tbi/bcerebel.shtml
 * The Cerebellum- The Cerebellum is located under the Cerebrum, at the back of the brain. It controls balance, movement, and coordination. It is also involved in attention and language.

Link: http://www.waiting.com/brainstem.html
 * The Brain Stem- The Brain Stem is located under the Cerebrum, and in front of the Cerebellum. It mainly controls involuntary functions such as respiration, digestion, circulation, and moving involuntary muscles such as the heart. Basal ganglia connected to the brain stem function as switching centers.

Link: http://www.umm.edu/endocrin/pitgland.htm
 * The Pituitary Gland- The Pituitary gland is responsible for controlling the release of hormones throughout the body. It is important in growth especially puberty. It can also be considered part of the Endocrine System.

Link: http://biology.about.com/od/anatomy/p/Hypothalamus.htm
 * The Hypothalamus- The Hypothalamus's most important function is to regulates your body's temperature using thermoreceptors and osmoreceptors. This is called homeostasis. If your body is too hot, the hypothalamus makes you sweat to lower your temperature. If your body is too cold, the hypothalamus makes you shiver to increase your body temperature.

Link: http://spinwarp.ucsd.edu/neuroweb/Text/br-800epi.htm
 * The Limbic System- The Limbic System is located in the middle of the brain. It consists of structures such as the hippocampus (processes short term memory into long term memory). It is important for memory, learning, and emotion.


 * Cerebrospinal Fluid - cerebrospinal fluid is a colorless fluid that flows through the brain and spinal cord. It acts as a barrier to prevent wastes from damaging the brain and to maintain homeostatic conditions. When there is too much cerebrospinal fluid, hydrocephalus (or hydrocephaly) results, causing swelling in the head. This can be reversed to an extent by tubes draining the excess fluid.

The Nerves
The nerves are the body's messengers. The send the brain's messages and commands to the corresponding parts of the body. The spinal cord is the long bundle of nerves running through the back of your body. It connects with the brain, and all the other nerves. The spinal cord is supported by your backbone. The nerves are made of cells called neurons bound together in bundles called fascicles and surrounded by the endoneurium, perineurium, and epineurium membranes. Neurons connect with each other to communicate. Electrochemical waves travel along the axon of one neuron, then move across a gap called a synapse. Sodium and potassium ions are pumped across the synapse to the dendrite of another neuron in a nerve impulse.



Types of Neural Cells
One type of neuron is the astrocyte, so named because it resembles a star.

Spinal Cord
Along with the brain, the spinal cord makes up the central nervous system. It is divided into 31 sections with pairs of nerves, making 62 nerves composed of sensory and motor neurons. The spinal cord contains grey and white matter.

Links

 * http://yucky.discovery.com/flash/body/pg000136.html


 * http://kidshealth.org/kid/htbw/brain.html