There is something like Serotonin Irritation Syndrome which can cause aggressive feelings and thoughts. Personally I tried to increase my serotonin twice, once with Tryptophan a few years ago and recently with Inositol. Both times I felt very aggressive. Maybe I should use it right before a chess game, who knows it helps ;)

It is sometimes mentioned that for people who are sensitive to psychosis (like me) this can be a tipping point towards aggressive behaviour.