Scientists have put their fingers on a new brain circuit involved in the munchies attacks that occur after smoking. It appears that the munchies are also triggered by brain cells that are supposed to turn down appetite, according to thenew study published in this week’s Nature magazine.

Scientists have found that under the influence of pot, these circuits switch their purpose. So instead of  advising you not to eat, they urge you to do so, even if your body doesn’t need any food, study author Tamas Horvath, a neurobiologist at Yale University School of Medicine explained.

“At first glance, the finding was completely “nonsensical.” It’s as if “you’re driving down a hill and you brake, brake, brake, and all of a sudden the brake becomes an accelerator,”

Horvath said.

Horvath and his team experimented on mice, by taking a look at nerve cells called pro-opiomelanocortin (POMC). They gave the mice a chemical that mimics the marijuana effects by fastening to cannabinoid receptors (the molecules in the brain involved in controlling your appetite, in feeling pain and other processes). Taking a look at the rodents’ brains to search for the active neural circuitry, they found that nerve cells that normally suppress appetite lit up.

Afterwards the team experimented turning nerve cells, or neurones on and off, while activating the cannabinoid receptors. By dampening the activity of the neurones, the mice became less likely to munch; on the other hand, while stimulating the neurones the mice were encouraged to eat more.

“We didn’t mean to find what we found. It was a simple controlled study where we wanted look at these neurons where we suspected they should be off, to see if they were off, and under these conditions if cannabinoids induce feeding. We found they sped up, which was a shocking surprise for us, “

Horvath said.

Horvath also said that his team and him are interested in finding the link between the munchies and other behavioural responses to smoking pot. For instance great things may result, as people with appetite suppression, if exposed to these cannabinoid signals, they are likely to have their hunger increased.