Hunger hormone negatively affects decision-making

Scientists from Sweden in an experiment with rats found that the so-called hunger hormone ghrelin leads to a decrease in the ability to make rational decisions and increases impulsivity.

According to Science Daily, a new study by scientists from the Salgrenska Academy at the University of Gothenburg in Sweden has shown that the hormone ghrelin, which is produced when a person is hungry, negatively affects decision-making and impulsivity control. “For the first time, we were able to show that an increase in the level of the hormone ghrelin makes the brain act impulsively, and also affects the ability to make rational decisions, ” - Associate Professor at the Salgrenska Academy Karolina Skibika.

Impulsivity is a complex process and consists of impulsive actions and impulsive choices. Many of us find it difficult to deny ourselves a snack, even if we know that lunch will be served soon. The authors of the study conducted an experiment on rats, which also had difficulty in giving up the immediate reward. The researchers trained rats to push a lever when a special signal was given, and they received a reward. When the rodents resisted the urge to press the button, they also received a reward, only more, but delayed in time.

Failure to resist the urge to press a button during a beep is a sign of impulsivity. It found that rats that were injected directly into their brains with ghrelin to simulate hunger were more likely to push the button rather than expect more rewards.

“A person who chooses immediate gratification, despite the fact that he may receive a large reward if he waits, is characterized as more impulsive, and therefore has a weaker ability to make rational decisions, ” the researchers say.

Scientists have found that higher levels of ghrelin lead to a refusal to expect more rewards. In turn, blocking the hormone significantly reduced impulsive behavior. “Even a short period of fasting increases ghrelin levels, which leads to impulsive behavior, ” says Carolina Skibika. Impulsivity is a hallmark of many neuropsychiatric and behavioral disorders such as ADHD, OCD, autism spectrum disorders, drug abuse and eating disorders, scientists say. High levels of the hormone cause long-term genetic changes in brain networks that are associated with impulsivity and the ability to make rational decisions.