INDULGING in a fatty meal after studying for an exam could boost your results. A study in rats shows that eating a certain type of fat produces a hormone that helps the brain cement short-term memories into long-term ones.

Daniele Piomelli and colleagues at the University of California at Irvine trained rats to complete two tasks: avoid an area that gave them a shock, and find a platform in a pool of water. Immediately after the training periods, they injected some of the rats with oleoylethanolamide (OEA) – a chemical produced in the small intestine of vertebrates which creates …