Different chemicals have different effects on behaviour.

Endorphins
Endorphins are neurotransmitters that are similar to the chemical morphine. They have the effect of reducing pain. Endorphins become more active in the body during extreme exercise (e.g. long distance running). Narcotic drugs have an effect similar to endorphins but they are not natural and may have side effects that endorphin’s do not have. It is thought by some that acupuncture works through helping to stimulate the release of endorphins throughout the body by triggering a pain response. Research has shown that acupuncture may work to reduce pain for a significant proportion of people tested, but not all.

Mental Health Disorders
Some neurotransmitter disorders can have a physiological affect which directly impacts upon a person’s psychology.
If we know what the neurotransmitters responsible are, then it is possible to manipulate our responses to certain chemicals and thereby alter our experiences. The psychopharmacology industry is built on our understanding of drugs which target synapses and influence mental states.

Parkinson’s Disease
Parkinson’s disease is caused by a degeneration of dopamine-releasing neurons in one part of the brain. It causes rigid movements, slow movements and tremors. Dopamine cannot be administered to people as a treatment because it will not pass from the blood into the brain.
However, a chemical called L-dopa may be used, because it will move into the brain and it converts readily into dopamine in the brain. It can help the sufferer to regain relatively normal movements. However, after years of use its beneficial effects become less noticeable and harmful side effects become more apparent e.g. nausea, hallucinations and appetite loss.

Depression
Decreased levels of serotonin are often found in people who suffer severe depression. There are studies that show low serotonin levels to be a risk factor in suicide. Serotonin has an inhibitory affect: it inhibits aggression, it inhibits depression, it can inhibit insomnia or excessive sleeping, and it can inhibit overeating or under-eating.

Tourette’s Disorder
This disease causes urges to perform repetitive movements such as tics, coughs and sniffs. There may also be involuntary sounds or utterances, such as expletives. Whilst genetics, psychological stress and other environmental factors play a role, once again, at the synaptic level there appears to be some involvement. Drugs which block dopamine or norepinephrine have been reported to alleviate symptoms. Also, dietary supplements which aid synthesis of serotonin or acetylcholine seem to help so it is likely that there is a mixture of transmitter imbalances involved. There are many other examples of neurotransmitter involvement in disorders.

Are you interested in finding more about the chemicals within the brain and how they affect behaviour? Read our Brain and Behaviour ebook now.