There are many different types of neurotransmitters. Some of the main types of neurotransmitters are acetylcholine, responsible for stimulating muscles; Norepinephrine, which is responsible for putting our nervous system on alert; Dopamine, which is associated with reward mechanisms; Serotonin, which affects mood and emotions, and endorphin, which is like your natural pain reliever. The people responsible for the discovery of these chemicals are Otto Loewi, who discovered acetylcholine in 1921. Acetylcholine was also the first to be discovered. Loewi also won the Nobel Prize for his discovery. Then in 1946 Ulf Von Euler discovered norepinephrine. And in the 1950s dopamine was discovered by Arvid Carlsson; in 1950 Eugene Roberts and J. Awapara discovered GABA or gamma aminobutyric acid. in the 1930s Vittorio Erspamer discovered serotonin. Those responsible for the discovery of endorphin were Solomon Snyder and Candace Pert in 1973. There are two types of neurotransmitters, inhibitory and excitatory. Inhibitory neurotransmitters balance mood and are easily depleted. Excitatory neurotransmitters stimulate the brain. Too much or too little of these chemicals can cause disorders such as ADHD and ADD. Neurotransmitters are chemicals that transmit signals across a synapse. A synapse is what allows a nerve cell to transmit an electrical or chemical signal to another cell. Subsequently the signal is transmitted to another nerve cell. Neurotransmitters in the brain are stored in small sacs from the synapse at the axon terminal end of the neurons. Axon terminals are projections of neuronal cells that conduct electrical impulses. Drugs can significantly alter neurotransmitters They can block or increase......middle of paper......you would be cured of depression. Neurotransmitters are not the same as neurons. And that's because, first of all, there are 100 billion neurons and only 100 known neurotransmitters. Neurons are cells while neurotransmitters are chemicals. Furthermore, once neurons are lost, they cannot be regained. Works cited "Neurotransmitters". Neurotransmitters. Np, nd Web. March 04, 2014."Introduction to the Brain." Anatomy of the brain: cerebral lobes. Np, nd Web. March 05, 2014"Neurotransmitter." Wikipedia. Wikimedia Foundation, 28 February 2014. Web. 04 March 2014."What are neurotransmitters?" What are neurotransmitters? Np, nd Web. 05 March 2014. “Mental Disorders.” Neurotransmitters. Np, ndWeb. March 10, 2014. “Neuroscience for Kids.” - Neurotransmitters. Np, nd Web. March 10, 2014. Ellis-Christensen, Tricia, and O. Wallace. WiseGeek. Conjecture, February 2, 2014. Web. March 10. 2014.