" In contrast to dopamine-fueled feelings of pleasure, feelings of happiness are caused by another neurotransmitter—serotonin. Serotonin also helps create feelings of contentedness, significance, and importance. Among other functions, serotonin is a mood stabilizer. Sure, dopamine will give you the quick pleasure rush, but serotonin will keep you happy in the long term—a positive upbeat mood that chases the blues away. "

― , The Brave Athlete: Calm the F*ck Down and Rise to the Occasion