International

You know you want it. Just one more piece. That extra bit of pudding will be calling your name come Christmas Day, and you know it'll be hard to say no. Well, in potentially good news for the sweet-toothed, the burger enthusiasts and indulgers of all things naughty over nice, Stanford scientists have identified an electrical signature in the brain that precedes dangerous impulses, and delivering a timely pulse might be able to keep them in check.

"Impulses are normal and absolutely necessary for survival," says Casey Halpern, assistant professor of neurosurgery at Stanford University School of Medicine and senior author of the new study. "They convert our feelings about what's rewarding into concrete action to obtain food, sex, sleep and defenses against rivals or predators."

While impulses can be good, they can also be bad and bring consequences far worse than a ruined beach body. Impulses can drive gambling addiction, violence, drug-taking and especially heinous acts like putting on an episode of The Bachelor. Halpern and his team have uncovered what they describe as the smoking gun behind these irresistible urges, first in mice and then in humans.

The team switched the diets of laboratory mice from low-calorie pellets to a high-fat version, and allowed them to eat as much as they wanted during an hour-long period every day, for 10 days. The mice developed quite an appetite for the fatty pellets by the end of the 10 days and were pretty much eating them non-stop.

And their brains showed it. Throughout the experiment, electrodes were hooked up to the nucleus accumbens, a region of the brain that is critical for processing rewards. The team saw heightened activity in this reward center around one second before the mice chowed down on fatty pellets, while no uptick was observed before other rewarding activities like eating standard food and interactions with younger mice.