Without a few unusual people, human behaviour would have remained a mystery - ordinary people whose extraordinary circumstances provided researchers with the exceptions that proved behavioural rules. Claudia Hammond revisits the classic case studies that have advanced psychological research.
Janet and Ron Reimer's twin sons, Bruce and Brian, were born in Winnipeg in Canada in August 1965. All went well until April 1966, when the twins were circumcised. In the process, Bruce suffered a catastrophic injury to his penis. A year later, on the advice of Dr John Money, founder of the Gender Identity Clinic at Johns Hopkins University Medical Centre in Baltimore, Bruce became Brenda and the Reimers began to raise their son as a daughter.
John Money published the case as one of successful gender re-assignment in 1975, when the twins were 9. Yet by the time Brenda was a teenager she was suicidal. When her parents finally told her the truth, Brenda decided to change back to her original gender; she became David Reimer.
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