If you notice you can’t quite focus on what you’re doing when you drink, recently published research has a possible answer.

A new paper published Dec. 2 in the journal Nature Communications focused on research from the University of Texas Health Science Center at San Antonio. Researchers found brain chemistry that may contribute to why people who drink have a hard time concentrating while they’re under the influence.

“When we want to focus on something, or when we stand up from a chair and become active, a brain stem nucleus releases a chemical called norepinephrine. Acute exposure to alcohol inhibits this signal in the brain,” said senior author Dr. Martin Paukert, assistant professor of cellular and integrative physiology at UT Health San Antonio, in a statement.

Norepinephrine, a naturally occurring hormone that also behaves as a neurotransmitter, is secreted by a brain structure called the locus coeruleus when you need to pay attention to something.

Before, scientists didn’t have a good understanding of what happens next, but in the new study, researchers demonstrated that norepinephrine attaches to receptors on Bergmann glia, which are supporting cells called astrocytes.

As a result, calcium rises in the cells.

“To our knowledge, this paper is the first description that norepinephrine in mammals directly binds to receptors on the Bergmann glia and activates them through calcium elevation,” Paukert said.

Researchers found that the inhibition of calcium rise in Bergmann glia did not explain why people are off-balance while drinking. Still, Paukert said “our findings are in line with current suggestions that the cerebellum also plays critical roles in non-motor functions, and that astrocytes are not only supporting basic brain maintenance, but they may actively participate in cognitive function.”

According to co-author Manzoor Bhat, Ph.D., professor and chairman of cellular and integrative physiology at UT Health San Antonio, these discoveries “will open up new avenues of defining the brain circuits that ultimately determine the state of alertness, and how chemicals that interfere with those circuits essentially dampen this inherent vigilance system of the brain.”