Why does the brain age?

American scientists from the Amen Clinic, Johns Hopkins University, the University of California at San Francisco and Google have found out what accelerated brain aging depends on. The results of the study were published in the Journal of Alzheimer.

The researchers studied more than 62,000 brain scans from more than 30,000 people aged 9 months to 105 years. Using computer tomography, the researchers assessed blood flow in various areas of the brain - its weakening is associated with aging.

“Based on the results of the largest brain imaging study ever done, we can track common disorders and other factors that lead to premature brain aging. Treating diseases that cause brain aging can slow or even stop this process.

Data on the effects of cannabis abuse is especially important, as marijuana is beginning to be seen as harmless in our culture.” says lead author Daniel Amen, a psychiatrist.

Using computed tomography, scientists analyzed the relationship of brain aging with exposure to various factors, including mental illness - bipolar disorder, schizophrenia, attention deficit hyperactivity disorder.

The researchers examined 128 areas of the brain to determine its age and compared it with the patient's actual age. The difference in the data indicated a good state or accelerated aging of the brain.

As it turned out, schizophrenia "aged" the brain by an average of 4 years, marijuana abuse - by 2.8 years, bipolar disorder - by 1.6 years, ADHD - by 1.4 years.

But depression and the ageing of the body itself, contrary to the assumptions of scientists, did not provoke accelerated ageing of the brain.

“This is one of the first studies based on data on the state of the brain of a large sample. Such large-scale studies are needed to answer the question of what happens to the structure of the brain and its functions during aging. The influence of modifiable and non-modifiable factors of brain aging can be used to make further recommendations for the preservation of cognitive functions”, MD George Perry explains.

“This article represents an important step forward in understanding what happens to our brains throughout life. The results show that we can predict a person's age from blood flow in the brain. In addition, we have laid the foundation for further study of how common psychiatric disorders can affect the circulation of the brain.” says the study co-author Sahit Egan.

And a team of American scientists from the University of Minnesota and the University of Cincinnati found that the executive functions of the brain are not related to gender, as previously thought. They presented the results of the study in an article in the journal Neuropsychopharmacology.

Executive functions are a set of high-level processes that allow you to plan current actions in accordance with the common goal, change the reaction depending on the context, and selectively pay attention to the right incentives. For example, seeing a delicious cake, a person suppresses the automatic desire to cut off a piece for himself, remembering that he is on a diet; about to cross a highway in England, a tourist from the United States changes the learned reaction, and looks first to the right and then to the left. Also, these functions are activated when new previously unseen stimuli appear, providing cognitive flexibility.

After conducting a meta-analysis of more than 150 works on executive functions, the researchers found that the effect of the gender of the subjects is either very small or absent. At the same time, it was found that the executive functions are influenced by the genotype, the development of the subjects during growing up and maturity, as well as the neural networks formed in the brain - all these factors were considered worthy of further study.

“Overall, we found little or no effect of sex differences on executive function,” the authors conclude. “It would be wrong to think that gender is the main factor that determines differences in executive function and cognitive performance.”

However, the researchers suggest that stress, drug abuse, head trauma and other external factors may affect brain function differently in men and women. They insist on further study of the influence of such factors, hoping that this will help reduce the risk of developing mental illness in the future.