A basic essay discussing how the brain sends messages throughout the body, how chemicals affect the brain, and explains the left and right brain.

Essay by eryka_sHigh School, 10th gradeA-, June 2004

download word file, 7 pages 3.7

How it works-

The human brain has 1,000,000,000,000 nerve cells (neurons) that process information. Neurons receive information from other cells through networks called dendrites. Then the neurons send the information in electrical impulses to other nerves. Then the message is passed on to other cells at points of contact called synapses. This causes the release of chemical neurotransmitter. Neurotransmitters are molecules that are used to communicate messages from a transmitting nerve cell to a receiving nerve cell. They spreads out across to another neutron which the neurotransmitter attached itself to and starts a receptor on the neuron and makes another action potential; repeating the cycle. Each neuron has about 1000 synapses so it can receive information from many other cells. If the receptor is clogged or any part of it is missing then one will have trouble communicating.

There are different kinds of neurotransmitters. The main ones are called Noradrenalin, Dopamine, Serotonin, and GABA.

There are transmitting and receiving nerve cells that are specially trained to receive and transmit them. For example with the noradrenalin neurotransmitter, two of its receptors are called alpha-1 and alpha- 2. Alfa-1 stimulates liver to sugar molecule conversions, making more glucose blood; it also stimulates consumption of oxygen, this causes energy.


Certain chemicals override brain activity and preside over logical thinking. Dopamine produces feeling of bliss when it rushes to the frontal lobes; it lessens pain and increases pleasure. Dopamine is also active in the addictive process.

Norepinephrine, which is actually produced from dopamine, flows through the brain stimulating adrenalin and the pounding of the heart. It is also responsible for alertness and orienting functions. High levels of Norepinephrine help mental focus and muscle performance. Low levels cause anxiety, lack of focus, and sleepiness.

Phenylethylamine, which is also found in chocolate, gives a...