The personality could be regulated by the immune system
The study of personality types is one of the main areas of research in psychology.
Several test proposals and personality systems have emerged from it, very useful both in applied psychology and in research. But nevertheless, still very little is known about what causes the appearance of the personality itself . We realize that there are differences in the patterns of behavior (and thinking) of people, but we do not know what is the origin of these. Genetics? Differences in learning? The answer to this issue, besides being a mystery, seems to be very complex.
However, a recent investigation has shed some light on the matter, and has done so from a possible answer that is surprising. A slope of our personality could be controlled by our immune system .
The origins of the sociable personality
The conclusions of the study, which have been published in the journal Nature and are signed by several researchers at the University of Virginia, point to the possibility that part of our social behavior has appeared under the influence that the immune system has in our brain.
The investigation was made from the study of several laboratory mice in whose body there was a shortage of a molecule called interferon gamma (IFN-y). This element has a very important role in the immune response to pathogens, so it could be said that it fights against diseases.
But its relevance not only remains in that, judging by what was observed in the mice. These rodents s and they were significantly less sociable than the rest , and his behavior resembled what happens in cases of autism.
In addition, by placing these animals under observation using the functional MRI technique, it was found that some areas of the prefrontal lobe were much more activated than is normal in individuals of their species. This was enlightening, because it is known that the prefrontal lobe plays an important role in the regulation of social behavior, and also appeases the orders that reach the cortex coming from the limbic system, which is the part of the brain responsible for the appearance of emotions. .
The immune system and the molecules to be more social
Once this had been observed, the researchers injected IFN-y in this group of animals and, just after, they saw how their behavior changed to that of a more sociable, completely normal mouse.
In addition, they verified that after introducing this type of molecule in the body of the mice, the amount of a neurotransmitter called GABA had increased, in charge of, among other things, inhibiting the activation of many neurons of the prefrontal lobe. This caused the level of activity in this area to drop to normal.
More studies, more evidence in favor
The same researchers did another type of study, this time from the evolutionary perspective, to see if the role of interferon gamma was as relevant as it appeared. For this they analyzed the genome of several animal species. In this way they discovered that those animals that had been sharing space with other members of their species were more predisposed to make the gene responsible for the manufacture of IFN-y more expressed, while the opposite occurred with those who had been more isolated .
That is, that these different animal species were genetically programmed to produce more IFN-and to be in social situations, even if they were not infected.
The implications of the study
The discovery carried out in this study is very relevant for two reasons.
The first one is that the most intuitive and apparently logical would be to think that it was social behavior that, making the contagion of diseases higher, had effects on the immune system of our ancestors, and not the other way around. This research breaks with this idea by placing the immune system as a possible trigger for the beginning of the sociable personality .
In addition, according to Jonathan Kipnis, one of the co-authors of the study, it was believed that the immune system and the brain each worked on their own, and when it was appreciated immunological activity in the brain was interpreted as a sign of disease. Therefore, knowing that certain immunological components can have such significant effects on the brain opens the door to future lines of research that allow us to know more and better about human and animal behavior.