Until she was 30, Ellen Forney, an award-winning Seattle-based artist, took her slightly unusual personality for granted. Her obsession with exercise, her impulsive sexuality, her bouts of ecstasy: she considered these things, however uncomfortable, a major part of who she was. After all, aren't all creative types given to strange moods, to pulling all-nighters, to forgetting to eat?

MARBLES: Mania, Depression, Michelangelo & Me, by Ellen Forney. Constable & Robinson, 2013, 256 pp., £12.99 (paperback)

But then, everything changed. Having spent one summer feeling low, she started seeing a therapist — a woman who, alarmed by her client's now increasingly "jazzed" mood, duly referred her to a psychiatrist. Forney was breezy about this. Her depression was long gone; she had barely slept in months, she had lost a lot of weight and she felt ... great.