A new study helps explain how alcohol affects self control. The study shows alcohol dulls the brain signal that warns people they are making a mistake. While drinkers are aware of their error, the alcohol causes them to care less about it.

According to Science Daily, the researchers from the University of Missouri measured brain activity in 67 participants as they completed a challenging computer task. One-third of participants were given alcoholic drinks; one third had a placebo drink, and one-third did not have any drink. The researchers studied the participants’ mood, as well as their accuracy in completing the task and how accurate they thought they were.

The study found the brain’s “alarm signal” in response to making a mistake was significantly reduced in the alcohol group compared with the other two groups. However, those who drank alcohol were no less likely to realize they had made a mistake. They were, however, less likely than those in the non-alcohol groups to slow down and be more careful after making a mistake.

“In tasks like the one we used, although we encourage people to try to respond as quickly as possible, it is very common for people to respond more slowly following an error, as a way of trying to regain self-control. That’s what we saw in our placebo group. The alcohol group participants didn’t do this,” lead researcher Bruce Bartholow said.

The study is published in the Journal of Abnormal Psychology.