Dysfunction in dopamine signaling profoundly changes the activity level of about 2,000 genes in the brain's prefrontal cortex and may be an underlying cause of certain complex neuropsychiatric disorders, such as schizophrenia, according to scientists. This epigenetic alteration of gene activity in brain cells that receive this neurotransmitter showed for the first time that dopamine deficiencies can affect a variety of behavioral and physiological functions regulated in the prefrontal cortex.