Abstract
In a cross disciplinary and wide ranging paper such as this, it seems useful to give most references to books or reviews that summarise current evidence or opinion. However, the factual statements are based on the primary literature, which I accessed in the usual way: from personal collections of reprints, from databases (such as BIDS and Medline, using keywords such as “stress” or “depression” coupled with other keywords such as “adrenal steroids,” “corticoids,” “serotonin,” etc), from reviews (some cited in this paper), from scanning key journals, and from contact with colleagues.