Describe the monoamine hypothesis of depression and discuss evidence that supports this hypothesis

What will be an ideal response?

Answer: Depression (without mania) reflects profound changes in mood, appetite, movement, and sleep. The monoamine hypothesis argues that depression reflects a reduced level of activity of the monoamine transmitters, specifically norepinephrine (NE) and serotonin (5-HT). A variety of treatments exist for unipolar depression (MAOI, tricyclics, serotonin reuptake inhibitors, ECT, and sleep deprivation). The tricyclic drugs block the reuptake of NE and 5-HT, while the serotonin reuptake inhibitors block only serotonin reuptake (resulting in more serotonin). The tryptophan deletion procedure lowers brain serotonin levels and can reinstate depression.