Until recently, the cerebellum—a dense, roughly fist-sized structure at the base of the brain—was mainly thought to co-ordinate the body’s movements. But new research published in Science shows that it helps to control social behaviours and the perception of rewards, too. In experiments on mice, Kamran Khodakhah of the Albert Einstein College of Medicine in New York City found that the cerebellum was directly linked to the ventral tegmental area (VTA), where brain cells synthesise dopamine, a feel-good hormone. By stimulating the mice’s cerebella at specific times—such as when the rodents wandered into a particular corner of their enclosure—Dr Khodakhah’s team could induce the release of dopamine and, over time, cause the mice to become “addicted” to the places that they associated with pleasure. Examining the function of the cerebellum opens up better understanding of (and improved potential treatments for) a range of brain conditions, from addiction to autism-spectrum disorder and schizophrenia.