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The physical mapping of the brain is still being explored. There is a lot that we do not know but there is a surprising a huge amount that we have discovered over the last 60 years. We know that the brain consists of individual neural cells that are separated by small gaps. This Nobel Prize winning theory was the borne from Santiago Ramon Y Cajal using Camillio's Golgi technique of impregnating individual neurons with silver. We now know that the neural cells consist of Dendrites, which reach out from the cell body to receive information from the previous neuron. The Soma or cell body that receives information and either sends, modify, or ends the message being sent. The Axon which looks like a tail and covered by a fatty substance called a myelin sheath, help reach out to the next neuron and sends whatever message to the dendrites of the next neuron through its terminals. Neurons send messages by electrical impulses. Neurons remain at rest in an internally negative state until it receives an electrical charge from the previous neuron. It is no longer considered to be polarized or resting. The Potassium ions that are found inside the neuron come out and the Sodium ions that are found on the outside go in the neuron to carry the message through the neuron. The neuron is then considered to be depolarized and ready to fire an impulse. When this impulse is fired the neuron experiences what is called the Absolute refractory period . This is a period in which the neuron cannot fire another impulse for a while. No matter how strong the incoming message. Or it may go through a Relative refractory period, a time in which the neuron is becoming polarized after the impulse can fire another impulse if the message is much stronger then usual. The synapse is an area composed of the axon terminal of one neuron, the synaptic space, and the dendrite or cell body of the next body. In this place interactions of the neurons takes place. Messages are released in chemicals by the terminals. These chemicals are called neurotransmitters. They are released and then reuptook by the nearby neuron's receptor cites on the dendrites. Neurotransmitters are still being investigated in their purposes but, there a few that we know well of. We know that neurotransmitters are excitatory (which increases the likelihood of the next neuron firing the incoming impulse or inhibitory