The neurobiology of treatment response to antidepressants and mood stabilizing medications.

As the neurobiology of mood disorders and the mechanisms of action of antidepressant drugs continue to be elucidated, there has been a shift in emphasis from changes in neurotransmitter release and metabolism to regulation of gene expression and neuroprotection. Evidence from animal studies suggests that drug therapy may act on specific transcription factors and target genes that regulate processes such as neuroprotection and neuronal survival. Clinical studies consistently identify changes in prefrontal cortex, hippocampus and amygdala that may be related to the course of illness and may be prevented with successful treatment. Together, these findings suggest that clinically relevant neurobiological correlations may ultimately be identified in patients who respond and remit to treatment. With these and future advances in the neuroscience of psychiatry, it may be possible to identify biological markers that will help in decisions about specific treatments for an individual patient.