Dr. C. George Boeree, professor of psychology at Shippensburg University, has several papers available at his website that are of great interest to anyone learning about personality and/or psychology.
Dr. Boeree has condensed the neurotransmitters and linked them to the part of the human experience that they influence and/or control.
(1) Acetylcholine is responsible for the muscles. It is found in sensory neurons. There is a link to the loss of acetylcholine in Alzheimer’s disease. With this disease, there is a 90% loss.
(2) Norepinephrine help keep our bodies on high alert. Stress depletes our norepinepnrine resources and exercise increases our supply. Amphetamines (speed) causes the release of it.
(3) Dopamine creates the reward or good feelings in the brain. Cocaine, opium, heroin, nicotine and alcohol increases the level of dopamine. I read somewhere several years ago that the first use of cocaine releases all the dopamine in the brain. That level of “high” only happens that first time and is not repeated in repeat use of the drug. Schizophrenias have excessive amounts of dopamine so drugs that block dopamine help them. Parkinson’s disease is the result of too little dopamine.
(4) GABA (gamma aminobutyric acid) is another inhibitory neurotransmitter which acts as a brake for too much anxiety. People with anxiety disorders generally have low supplies of GABA. Epilepsy is caused by lack of GABA.
(5) Glutamate is the most common neurotransmitter and may be as much as 50% of all neurons. ALS, or Lou Gehrig’s disease, produces an excess of glutamate and may be linked to other nervous system problems.
(6) Serotonin is linked to emotion and mood. Depression, anger control, obsessive-compulsive disorder and suicide my be due to low levels of serotonin. Appetite and food problems may also be linked to too little serotonin. It also is evident in perception. Hallucinogens like LSD blocks transmissions in perception.
(7) Endorphin is similar to the opioids (heroin, opium, morphine) and acts to reduce pain and increase pleasure.