Your brain could grow bigger with increasing age – not smaller. Here is what we know

I recently wondered if I still have a healthy brain when I get older. I have a professorship in a neurology department. Nevertheless, it is difficult for me to assess whether a certain brain, including my own, suffers from the early neurodegeneration.

However, my new study shows that part of her brain is more likely to be age than with age and not degenerated.

The reason why it is so difficult to measure neurodegeneration is how complicated it is to measure small structures in our brain.

Modern neuroimaging technology enables us to recognize a brain tumor or identify an epileptic lesion. These anomalies are several millimeters of size and can be represented by a magnetic resonance scanner (MRI), which works stronger than the natural magnetic field of the earth at around 30,000 to 60,000 times. The problem is that human thinking and perception work on an even smaller scale.

Our thinking and perception happens in the Neocortex. This outer part of our brain consists of six layers. When she touches her body, the four of your sensory cortex is activated. This layer is the width of a grains of sand – much smaller than what MRI scanner in hospitals can normally represent. If you modulate your body feeling, for example by trying to read this text instead of feeling the pain from your bad back, the layers of five and six of your sensory cortex are activated – which are even smaller than Layer four.

For my study, which was published in the Journal Nature Neurosciences, I had access to a 7 -esla -mrt scanner, which offers a five -time image resolution as a standard -MRI scanner. It makes snapshots of the fine brain networks during perception and is visible.

With a 7 -Tesla scanner, my team and I examined the sensory cortex in healthy younger adults (approximately 25 years old) and healthy older adults (approximately 65 years) to better understand the aging of the brain. We found that only five and six layers that modulate body awareness showed signs of age -related degeneration.

The fourth layer, which was enlarged in my study in healthy older adults in healthy older adults, was enlarged. We also carried out a comparative study with mice. We found similar results in the older mice because they also had a more pronounced layer of four than the younger mice.

Evidence from our study of mice, which included a third group of very old mice, showed that this part of the brain can degenerate in the more advanced age.

Current theories assume that our brain gets smaller when we get older. But the results of my team partially contradict these theories. It is the first proof that some parts of the brain grow up with the age of normal older adults.

Older adults with thicker layer four are expected to react more sensitive to touch and pain and (due to the reduced deep layers), they have difficulty modulating such sensations.

In order to better understand this effect, we examined a middle -aged patient who was born without an arm. This patient had a smaller layer four. This indicates that their brain has received less impulses compared to a person with two arms and therefore developed four less mass in layer. Parts of the brain that are used more develop more synapses, therefore more mass.

Instead of degenerating systematically, the brains of older adults seem to at least partially get what they use. The aging of the brain can be compared with a complex machine, in which some frequently used parts are well oiled, while others that are used less often are roasted. From this perspective, the aging of the brain is individually, shaped by our lifestyle, including our sensory experiences, reading habits and cognitive challenges that we take on in everyday life.

In addition, it shows that the brains of healthy older adults preserve their ability to reconcile with their surroundings.

A lifetime experiences

There is another interesting aspect of the results. The pattern of brain changes that we have found in older adults -a stronger sensory processing region and a reduced modulation region -shows similarities to neurodiving diseases such as autism spectrum disorder or the attention deficit hyperactivity disorder.

Neurodivending diseases are characterized by increased sensory sensitivity and reduced filter capabilities, which leads to problems with regard to concentration and cognitive flexibility.

Show our results that aging drives the brain towards neurodiverse disorders? Older brains of adults have been formed through a lifetime, while neurodiver -related people are born with these brain patterns. So it would be difficult to know what other effects could build the brain mass with age.

However, our results give us some indications of why older adults sometimes have difficulty adapting to new sensory environments. In such situations, for example confronted with a new technical device or a new city, the reduced modulation skills of layers five and six can become particularly obvious and increase the likelihood of disorientation or confusion. It can also explain reduced skills for multitasking with age, e.g. B. the use of a mobile phone when walking. Sensory information must be modulated to avoid disorders if you do more than one thing.

Both the middle and the deep layers had more myelin in older mice and humans, a high -fat protective layer that is of crucial importance for nerve function and communication. This indicates that people over the age of 65 have a compensation mechanism for the loss of the modulation function. However, this effect seemed to collapse in the very old mice.

Our results provide evidence of the power of a person’s lifestyle for the design of the aging brain.

Esther Kuehn is a professor of neurosciences at the University of Tübingen.

This article will be released from the conversation under a Creative Commons license. Read that Original article.