SAN ANTONIO – A new study published by researchers at UT Health San Antonio found that alcohol impacts more than a human’s motor skills. It also discovered how it impacts a person’s decision-making under the influence.
“Even though one can still perfectly walk and maybe feels confident that one can make the right decisions,” UT Health San Antonio researcher Dr. Martin Paukert said. “There may already be serious effects on brain signaling that one is not aware of.”
The study, which was funded in part by grants from the Robert J. Kleberg, Jr. and Helen C. Kleberg Foundation, the National Institute on Alcohol Abuse and Alcoholism and the National Institute of Mental Health, was published earlier this month in Nature Communications. Researchers examined mice to give them an idea of how things would translate to a human.
Researchers studied a cell type in the brain called astrocytes. It makes up a network throughout the brain that activates when a mouse is active.
Paukert said that when the astrocytes become active, it produces a chemical called norepinephrine that creates an increased amount of calcium that is released into the body. The results of the study found that when under the influence of alcohol, the body does not activate norepinephrine, which in turn does not increase calcium production.
“Norepinephrine is known to be released when we are actively paying attention or actually also when we get rewarded,” Paukert said. “And so that is basically one of the main effects of alcohol, is that it inhibits the release of this chemical norepinephrine.”
Researchers found that while alcohol impacts a person’s ability to walk and talk, they found that the lack of norepinephrine may also impacts a person’s ability to make decisions while under the influence.
“On this calcium activation loss, actually much longer than the animals had problems walking, so there was basically a disconnect between motor coordination and the effect at the cellular basis,” Paukert said. “One of the main results of this study is that lets us speculate that this activation in these cell type has a role that is motor control independent, but maybe rather for the cognitive effects of alcohol exposure.”
Another thing researchers found was that when the release of norepinephrine is blocked by alcohol, the body will try to make it up through withdrawals, which may prolong the problem with decision-making.
“This particular chemical that we are studying, this norepinephrine, it has been known already from different types of studies that it needs a certain precise balance,“ Paukert said. “If the signaling is too weak, that is for the performance not good. But if the signaling is actually too strong, if it overshoots, so to speak, it is also not good for the performance. So it requires a certain, pretty precise balance. And for that reason, it may be that in the acute exposure where it’s then suppressed, it may...cause one type of problem. Whereas the changes in the situation where the signaling is overactive, it may be detrimental for our performance of decision making, for example, in a different way.”
Researchers also believe they can take what they learned in this study and see how the network of cells that are activated by activity are impacted by things other than alcohol.
“This suppression of the release of that chemical that we found with acute exposure to alcohol, it is interesting that the neurons that produce that chemical are degenerating also during neurodegenerative diseases,” Paukert said. “So, for example, Alzheimer’s disease or Parkinson’s disease...one could predict that just in a much longer timescale, over decades, that would be also a reduction of the same form of signaling that gets acutely suppressed when we get exposed to alcohol.”
“It is going to be complicated, but it gives us, at least, already a hint of what implications and what other diseases, similar processes might be involved.”