Especially between the ages of 40 and 50 (what doctors call the fifth decade) various organs in our body begin to deteriorate: muscle mass is lost, vision becomes less sharp, joints begin to fail, for example.

But something different happens in the brain.

Rather than a progressive deterioration process, what happens is a kind of reconfiguration of its internal “wiring.”

That is one of the conclusions reached by the team of researchers from Monash University in Australia, after analyzing more than 150 studies on how our body ages and, especially, our brain.

“The brain, although it barely represents 2% of our body, consumes 20% of the glucose that enters our body. But with age it loses that ability to absorb that nutrient,” explains neuroscientist Sharna Jamadar, from Monash University.

“What the brain does is a kind of reengineering of its systems to be able to take better advantage of the nutrients it can now absorb.”

According to scientists, this process is “radical” and results in different neural networks becoming more integrated in the following years, with effects on the cognitive process.

The main conclusion they have reached is that our brain is made up of a complex network of units that are in turn divided into regions, subregions and, in some cases, individual neurons.

“Taking this into account, during our growth and youth, this network and these units are in a process of high connectivity, which is reflected, for example, in the learning of specific subjects,” says the neuroscientist.

That is why during these years it is easier for us to learn specialized sports or a new language and, in general, to develop our skills.

However, according to the analysis carried out by the Monash University team, led by Dr. Hamish Deery, once we reach the age of 40, these circuits change radically.

“This results in less flexible thinking, less response inhibition and reduced verbal and numerical reasoning,” explains Jamadar.

“These changes are seen in people during this so-called fifth decade, which coincides with the findings that changes in the connectivity of these networks peak when you go from 40 to 50 years old,” he adds.

This is because the circuits connect more with the networks that handle general topics and not specific ones, as occurs in the previous years.

“It is as if before 40, the circuits go through the brain units connecting with very sophisticated networks. After 40, what we see is that the circuits connect with all the circuits, almost without discrimination"