© Current Biology, DiFeliceantonio et al
An opium-like brain chemical prompts rats to gorge themselves on chocolate treats like M&Ms, new research in Current Biology finds.
A part of the brain usually associated with movement may also control our responses to rewards, according to new research that finds stimulation of the region with an opium-like chemical can make rats gorge on M&M candies.
The brain naturally produces opioids
, or chemicals with similarities to the drug. One of these, enkephalin, induced hungry rats to pounce on chocolate treats
faster the more of the chemical they produced, researchers report online today (Sept. 20) in the journal Current Biology.
When scientists dosed the rats with a big jolt of enkephalin in a brain region called the neostriatum, the rats became eating machines
, downing the equivalent of a 150-pound (68 kilogram) person eating 7 to 8 pounds (3.1 to 3.5 kg) of M&Ms in an hour, said study researcher Alexandra DiFeliceantonio.
"This drug injection causes them to eat just obscene amounts of food," DiFeliceantonio, a graduate student in biopsychology at the University of Michigan, told LiveScience.