False-colour positron emission tomography (PET) scan highlighting limbic areas in a human brain. A receptor for the inhibitory neurotransmitter GABA is visualised here in regions of the brain ...

It was 1985 and John Lawn had seen enough. In Boston nightclubs and Dallas bars, MDMA—better known by its street name, ecstasy—had become an enormously popular recreational drug. It had also terrified ...