Theory of Chemical Imbalance

Because the brain and nerves rely upon chemical reactions, it is a common hypothesis that "misfires" like clinical depression, anxiety attacks, attention deficit disorder and psychosis may have chemical causes as well.

History

• The theory of chemical imbalances was first described in the 1950s, but, as long back as ancient Greece, physicians described imbalances of the "humors," of earth, phlegm, ether and fire.

Neurotransmitters

• Neurotransmitters are the chemicals that send reactions along nerve paths (like pain from a burned finger, and then a reaction "order" to snatch the finger away). Specific neurotransmitters are involved in emotional reactions and moods.

Norepinephrine

• Early chemical imbalance theory on depression focused upon the neurotransmitter norepinephrine, and presumed a deficit of norepinephrine activity.

Seratonin

• Modern depression theory focuses upon the neurotransmitter serotonin, and poor transmission of serotonin in nerve paths. Thus Selective Seratonin Reuptake Inhibitors (SSRIs) like Prozac "spark" transmission of serotonin.

Arguments

• The chemical imbalance theory is broadly accepted by the media. It may explain psychosis, but there are situational causes for depression and anxiety like post-traumatic stress disorder, and behavioral and environmental causes of attention deficit disorder. The symptoms may respond to medications, but do not resolve the situational causes.