Since serotonin is one of those feel-good neurotransmitters, having more of it likely improves some of the other symptoms like withdrawal and flat affect.
This lack of interest in money meant that all the brothers would probably be poor for ever, but Angel still admired his father's belief that money was not important.
All passiveness and unconcern had dropped from them. They were alert and active, anxious that the work should go well, and fiercely irritable with whatever, by delay or confusion, retarded that work.
" So why's Dumbledore been so keen to keep me in the dark? " Harry asked, still trying hard to keep his voice casual. " Did you—er—bother to ask him at all? "
He bent suddenly to retrieve his hat and she had one glimpse of his face. It was the unhappiest face she was ever to see, a face from which all aloofness had fled.