Psychiatry General 3d5ce6e9 In depressions, there is deficiency of ? A 5-HT B Acetylcholine C Dopamine D GABA High-Yield Explanation Ans. A. 5-HTDepression = Decrease in serotonin and norepinephrine.Serotonin is the most imPoant neurotransmitter in depression.Mania= Increased of norepipherine.