In healthy individuals, determining what and how much to eat is controlled by a variety of factors, including what is available, how hungry the person is and what they like. Not so in anorexia. Kaye’s use of functional magnetic resonance imaging (fMRI) of the brain has teased out other important details. Unlike most people, whose brains respond strongly to rewarding things such as sweets, people with anorexia are generally far more sensitive to punishment (the removal of something pleasant) than reward.