If you find yourself hoovering snacks in the middle of the night — yet still feel ravenous post-binge — blame your brain. A new study from BYU 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.

The study, published in the journal Brain Imaging and Behavior, used functional MRI examine how people’s brains react to pictures of both high- and low-calorie foods at different times of the day. Participants looked at 360 snapshots during two separate sessions that were held one week apart (the first during morning hours, the second at night).

The images included low-calorie foods like veggies, fruits, fish and grains, and high-calorie foods like candy, baked goods, fast food and ice cream. 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: 7 Calorie-Cutting “Skinny Hacks” for Healthier Mac ‘n Cheese

“We thought the responses would be greater at night because we tend to over-consume later in the day,” professor of exercise sciences and study co-author Lance Davidson said in a statement. “But just to know that the brain responds differently at different times of day could have implications for eating.”

The study also found participants were more food-obsessed at night even though their hunger and “fullness” levels were similar to other times of the day. “You might over-consume at night because food isn’t as rewarding, at least visually at that time of day,” added lead study author Travis Masterson. “It may not be as satisfying to eat at night so you eat more to try to get satisfied.”

It’s a vicious cycle: Even after pulling a Cookie Monster, it feels as if your stomach’s this cavernous hole that can never be filled—and even though we think otherwise in the moment, the perfect snack won’t appear if you open the fridge “just one more time.” While this study is preliminary and further research is needed to better understand the findings, it’s a solid step toward learning how our brain effs with our eating habits and how to handle it.

In the meantime, keep in mind (as you’re drowning your ice cream with chocolate sauce) that your midnight snack probably won’t be as satisfying as it should be—you know, to help curb the whole going-back-for-seconds thing. Swap out your go-to midnight snacks with healthier options, up your sleep quota, and whatever you do, don’t watch action flicks while you’re noshing. That’s just asking for trouble.

READ MORE: 7 Calorie Cutting “Skinny Hacks” for Healthier Cocktails