We often think that the adverse effects of heavy drinking may not reflect in tasks such as driving, especially if the blood alcohol concentration is zero, but recent research has found that it is not true.

Study subjects took simulated driving tests on the night after they consumed 10 alcoholic drinks and their blood concentrations had returned to zero. The results of the tests were compared to their performance on similar tests when they did not drink.

The study showed that hangovers can markedly elevate errors while driving. They portrayed slower reacting times, and drove at inconsistent speeds.