Thus they are more prone to depression. Our bodies contain approximately five billion nerve cells. Three billion of these are located in our brain. The other two billion are scattered throughout our body. Between two adjacent nerve cells is a small space called a synapse.
Nerve impulses travel through the nerve cell as electrical impulses.
At the synapse these electrical impulses are converted into chemicals called neurotransmitters. Neurotransmitters carry the impulse to the next cell, where it is converted back into an electrical impulse. This process happens at the juncture of each nerve cell. Some people, because of their genetic constitution, tend at certain times in their lives to produce an inadequate amount of one or more of the neurotransmitters. Then the nerve impulse does not get through with the strength it should.