PS268 Chapter Notes - Chapter 4: Monoamine Neurotransmitter, Major Depressive Disorder, Positron Emission Tomography
Chemical Theories of Behaviour
-differences between two people might be explained by a difference in the chemical makeup
of their brains, or changes in individual's reactions from one day to the next explained in
terms of shifting tides of chemicals
Monoamine theory of mood:
-the major theory guiding treatment of clinical depression proposes that too little activity of
the monoamine neurotransmitters can cause depression, and too much causes manic state
-monoamine enhancing drugs (amphetamines and cocaine) elevate mood, and chronic doses
can produce manic episodes
-medications that augment actions of monoamines by interfering w their uptake have been
used to successfully treat depression for 40+ years
-because the drugs elevate mood right away, but the side effects are not apparent for
sometimes weeks, the underlying cause of depression is more complex than a simple
proposed neurochemical imbalance
-to date, no single neurochemical theory of depression has yet obtained sufficient
experimental support to be considered an explanation
Document Summary
Differences between two people might be explained by a difference in the chemical makeup of their brains, or changes in individual"s reactions from one day to the next explained in terms of shifting tides of chemicals. The major theory guiding treatment of clinical depression proposes that too little activity of the monoamine neurotransmitters can cause depression, and too much causes manic state. Monoamine enhancing drugs (amphetamines and cocaine) elevate mood, and chronic doses can produce manic episodes. Medications that augment actions of monoamines by interfering w their uptake have been used to successfully treat depression for 40+ years. Because the drugs elevate mood right away, but the side effects are not apparent for sometimes weeks, the underlying cause of depression is more complex than a simple proposed neurochemical imbalance. To date, no single neurochemical theory of depression has yet obtained sufficient experimental support to be considered an explanation.
