The singer Tulisa has been banned from driving for 15 months, joining the likes of Paris Hilton and Justin Bieber, who were also caught over the limit while behind the wheel. But why is drink driving so dangerous?
Everyone knows it’s stupid to drive when you’re drunk. But a small amount of alcohol won’t necessarily make you drive in a wobbly way. Instead, it’s the effect on our decision making that poses a real risk.
Alcohol is a depressant which slows down the reactions of cells in the brain. It affects a whole slew of neurochemical pathways, but some of the first neurons to be affected control judgment. In an old study, bus drivers were given different amounts of whisky to consume, and then drove their buses – off road – between a pair of white posts, which were brought narrower and narrower.
Initially at least, there was little difference in how well the bus drivers could drive between the posts. But when the gap became narrower than the bus, those who were sober stopped, while those who had had a drink tried to drive through anyway.
So, the loss of judgment caused by a small amount of drink can lead to risk-taking and, as in Tulisa’s case, big trouble.
Dr Daniel Glaser is director of Science Gallery at King’s College London