Brain commits suicide
The brain reaches its full size around the age of six, and for a long time researchers thought it was fully developed. But no – for about 15 years, the brain goes through an extensive demolition and rebuilding phase.
After the sixth year of life, the brain hardly produces any nerve cells anymore, because they already need far more than they need. As a result, some nerve cells commit suicide, and in some parts of the brain, more than half of all nerve cells die during childhood and adolescence. Many connections between nerve cells – called synapses – also begin to deteriorate.
In particular, the brain removes nerve cells and connections that are little or not used. The process can be compared to a sculptor who removes the excess from a stone, until the final shape remains.
This thinning is quite drastic, but studies show that it is essential to strengthen the remaining nerves.
Remodeling affects IQ
In an American research scientists followed the brain development and mental skills of a group of children over a number of years. For example, it turned out that the more the nerve cells in the upper part of the frontal lobes were thinned out, the better the children became at remembering words.
A similar one study also showed that thinning out nerve cells in the posterior frontal lobes improved fine motor skills in children.
As the brain breaks down old connections, it also forms new ones between existing nerve cells. And this interplay between tearing down and building up throws a teenager’s intellectual faculties upside down.
Neurologist Cathy Price of University College London mat The IQ of a group of teenagers between the ages of 14 and 18 over four years. Some of them dropped IQ by 20 points, others rose by 23 points. And in the same person, linguistic intelligence could increase considerably, while the abilities related to problem solving and spatial awareness weakened considerably.
These changes were related to the way certain brain centers were strengthened or broken down.
The teen is vulnerable
The major changes in the teen brain follow a specific pattern, with the posterior brain centers maturing first, while the frontal lobes in the front of the brain are not fully functional until after age 20. This may explain the lack of impulse control in teens.
In an American test from 2018, teens could choose to receive a small amount of money immediately or wait six months for a larger amount. The younger the teens were, the less patient they had. And brain scans showed that the least patient had yet to form strong nerve connections between the frontal lobes and the brain’s reward center.
The frontal lobes, which house our mind, are therefore not yet able to dampen the impulses of the reward center sufficiently. A similar lack of impulse control is seen in people with brain damage who have parts of the frontal lobes destroyed.
Teenagers’ frontal lobes also haven’t finished building connections with brain regions like the amygdala and sgACC, both of which play a role in emotions like joy and fear. As a result, teens also struggle to control their emotions – and it doesn’t take much to get angry or burst into tears.
You can see this on social media, for example. And to study this, psychologist Jennifer Silk of the University of Pittsburgh in the US created her own version of a social media site where teens can choose or reject each other while their brains are scanned.
In a study from 2022, Silk showed that rejection triggered high activity in the brain region sgACC. This is less common in adults, suggesting that the activity is due to the immature brains of teens.
In a follow-up study a year later, Silk found that the teens who had high activity in the sgACC in the experiment were more likely to have symptoms of depression. So the immature brain is very vulnerable, which may be why teens are at such a high risk for mental disorders.
As it turned out from a Brazilian study from 2020 that a quarter of the world’s teenagers have a psychiatric disorder, and from other analyzes that the problem is growing every year. The cause of the increase is unknown, but researchers are looking for it in everything from social media to sleep deprivation.
Chaos feeds creativity
Teenagers are also vulnerable in other ways. Their unfinished brain makes them more risk-taking, defiant and careless. For example, 15-19 year olds are six times more likely to die in an accident than 10-14 year olds. Young people are also more likely to end up in crime or start using drugs.
However, the risky and impulsive behavior of teenagers is not always a disadvantage. A Dutch research indicates that the chaotic teenage brain is more creative and better at thinking outside the box than the mature adult brain.
When the teens in the experiment learned something new, they were better than adults at using this new knowledge and combining it with existing knowledge to find new and original solutions to a problem. The Dutch researchers think that the major renovation will make the teenage brain more flexible, so that young people can adapt better to new situations and challenges.
Anyway, the teenage brain will also be complete one day. The process of thinning out excess brain cells will slow down and new connections will be made between brain regions such as the frontal lobes and the reward center.
This will quickly put a stop to teens’ creative thinking, but on the other hand, the youngsters will now be able to make more thoughtful, sensible choices—with less chance of emotional and sometimes violent attacks on their uncomprehending parents.
2023-08-26 07:46:22
#Teenagers #people #brain #injuries
