Insight into feelings of hunger

New research from Northwestern University’s Feinberg School of Medicine reveals how hunger works in the brain. The study involved testing people, first after feasting on up to eight donuts until they were unable to eat anymore, then on another day, after fasting for eight hours. The researchers looked at brain function when subjects were shown pictures of donuts and screwdrivers. After eating as many donuts as possible, subjects showed little brain activity when shown pictures of donuts. However, when shown pictures of donuts after fasting, two areas of the brain showed significant activity. These two areas were the limbic brain and the brain’s spatial awareness network. Marsel Mesulam, who directed the study, said: “If we didn’t have this part of the brain, every time you passed by a bakery you would have no control over your eating. If your nerve cells fired every time you smelled something edible, then you’d eat all the time, not just when you’re hungry.” The study helped Mesulam understand his own behaviour. “Now I know why I can’t resist walking into the bakery some days when I smell fresh scones,” he said.