Serotonin is one of the most important chemicals used by neurons and nerve cells to communicate with each other, but its effects on behavior are still not entirely clear to neuroscientists, who have spent decades trying to establish a comprehensive theory that explains its effects. functions. However, it is not easy to isolate serotonin to understand what role it plays in learning .
Now, an international team of scientists from the Champalinaud Foundation, in Portugal, and the University College (United Kingdom), has managed to take a step forward in this knowledge thanks to a new mathematical model. The results are published in Nature Communications .
Among other things, they have discovered that serotonin (5-HT) is capable of accelerating learning in mice , according to the study. The experts responsible for the research observed that by artificially activating serotonin neurons through the application of light , the mice used in the laboratory adapted their behavior to a new situation more quickly and were more agile to assume changes that required flexibility .
For Zach Mainen, one of the authors of the study, “these rodents knew how to give more relevance to the new information and, consequently, they were able to change their minds more quickly when those neurons were activated”. Until now it was already known that serotonin contributes to increasing brain plasticity and this study contributes to reinforcing that idea. At the same time, research shows that this neurotransmitter is more than just a mood enhancer.
Thanks to these new findings, neuroscientists will be able to better understand why antidepressants known as SSRI (selective serotonin reuptake inhibitor) are more effective when combined with behavioral therapies , designed to reinforce learning from behavioral strategies. whose objective is to reduce or eliminate depressive symptoms.
To carry out their experiment, the study authors introduced the mice into a chamber in which they had to activate a water dispenser located to their right and left that discharged water or not depending on certain probabilities. Madalena Fonseca, from the Champalimaud Foundation, observed that the amount of time the rodents waited between the various attempts to find water was variable, as sometimes they tried immediately, hitting the dispenser instantly, and other times they took a little longer to activate it.
This variability made the researchers think about the possible existence of a new effect of serotonin on the decision-making of the animals. Regarding the role of SSRIs in the treatments of psychiatric disorders, the authors suggest that serotonin increases the plasticity of the brain by influencing the rate of learning.
CAPTION
Photomicrograph of serotonin-producing neurons (in pink) in the mouse brain.
CREDIT
Matias, Lottem et al./CCU
