The Divided Mind by Edward Bullmore review – do we now know what causes schizophrenia?

A brilliant history of psychiatric ideas suggests we are on the cusp of a transformation in our understanding of severe mental illness

In 1973, an American psychologist called David Rosenhan published the results of a bold experiment. He’d arranged for eight “pseudo-patients” to attend appointments at psychiatric institutions, where they complained to doctors about hearing voices that said “empty”, “hollow” and “thud”. All were admitted, diagnosed with either schizophrenia or manic-depressive psychosis. They immediately stopped displaying any “symptoms” and started saying they felt fine. The first got out after seven days; the last after 52.

Told of these findings, psychiatrists at a major teaching hospital found it hard to believe that they’d make the same mistake, so Rosenhan devised another experiment: over the next three months, he informed them, one or more pseudopatients would go undercover and, at the end, staff would be asked to decide who had been faking it. Of 193 patients admitted, 20% were deemed suspicious. It was then that Rosenhan revealed this had been a ruse as well: no pseudopatients had been sent to the hospital at all. Not only had doctors failed to spot sane people in their midst; they couldn’t reliably recognise the actually insane.