Your eyes aren’t the only thing playing tricks on you at night. A new study revealed that some areas of the brain don’t get the same “food high” at night—so that bag of Oreos you’re about to devour may feel about as satisfying as a rice cake. Participants in the study were shown a cornucopia of images ranging from low to high calorie foods. Natch, researchers found a greater spike in brain activity in response to the high-calorie images, but were surprised to discover lower reward-related brain activity when the images were shown at night — in other words, your brain was less satisfied than it normally would be by the high-calorie images, hence why you may be encouraged to want more.

READ MORE: Snack Study: Your Brain Doesn’t Get the Same “Food High” at Night