Compare and contrast different neuronal and neurotransmitter abnormalities on behaviour.

The brain is an incredible organ. It contains billions of brain cells, or neurons, with multiple connections to one another. Information is sent between neurons via chemical messengers called neurotransmitters, which cross the small synapse, the miniscule gap between two neurons. All of the bodys functions, from the most simple to the most complex, depend on the transmission of these chemical messengers between the cells of the brain. Therefore, the health of neurons in the brain and the way they transmit their array of neurotransmitters crucially affects behaviour….(short extract)