All in the mind?

After the death of Sigmund Freud (1856–1939), the father of psychoanalysis, psychiatry underwent a schism and has remained divided ever since. Broadly, one camp has promoted the use of drugs as crucial to the treatment of behavioural problems such as addiction and depression, whereas the other has regarded drugs as a last resort, only to be used after cognitive therapies have been tried and have failed. This dichotomy has also influenced our understanding of behaviour and behavioural disorders: some argue that psychological problems are rooted in molecular neurobiology—and are thus amenable to drug intervention—whereas others contend that events at the molecular level alone cannot explain the complex psychotic conditions from which humans can suffer.