How to rejuvenate your brain

What is neuroplasticity

Neuroplasticity is the ability of the brain to form new neural connections and change under the influence of experience. It is best developed during childhood and adolescence, when the brain is just developing. Until recently, it was believed in neuroscience that after a person has passed the stage of personality formation, it is very difficult or even impossible to correct the effects of early experience.

What if we could return the brain to its early plastic state? Scientists are now exploring this possibility in animals and humans. It is believed that during the most important stages of brain development, the neural circuits that are involved in the development of behavioral patterns are still being formed and are especially sensitive to the influence of new experiences. If we understand what starts and stops their formation, we can learn how to restart them on our own.

The plasticity of the brain can be compared to molten glass. Glass in this state is very malleable, but hardens rather quickly. However, if you put it in the oven, it will change shape again.

Researchers were able to do something similar with such a human property as absolute ear for music. Absolute pitch is the ability to accurately identify or reproduce any note without first listening to previously known sounds. This is a very rare occurrence, occurring in about 0.01% of people.

Usually this skill is observed in those who started studying music before the age of six. When learning begins after age nine, perfect pitch develops much less often, and among those who began learning as an adult, only a few such cases were found.

In 2013, scientists at the University of British Columbia conducted a study among participants without musical training, in which they tested whether the ability to develop absolute pitch, Valproate reopens critical-period learning of absolute pitch, could be restored. … During the study, 24 participants were divided into two groups. Some received a placebo, while others received a special mood-stabilizing drug (valproic acid, which is commonly used to treat bipolar disorder). Then, for two weeks, all participants were trained to associate common names such as Sam and Sarah with six different notes from a twelve-tone musical scale. Then the drugs in the groups were changed: participants who first took placebo switched to valproic acid, and vice versa.

At the end of the experiment, the scientists found that those who took the special drug were significantly better at identifying the correct note. The effect was impressive even when considering the possible effects of valproic acid on the mood and cognitive function of the participants.

The results of this experiment interested many scientists. But how can we return the brain to its former plasticity?

How to restore plasticity to the brain

On the one hand, the neuroplasticity of the brain depends on its structure. In animals and, most likely, in humans, a perineuronal network, a special intercellular substance that prevents neurons from changing, forms over time. On the other hand, plasticity is also related to the molecular structure of the brain, and this is where special drugs can help.

It turns out that there are several substances responsible for the beginning and end of the stages of brain development. Among them is histone deacetylase (HDAC). This substance stops the production of proteins that stimulate plasticity, and thus leads to the end of the period when learning is easy. Valproic acid blocks the action of HDAC and partially restores brain plasticity.

You are now, of course, wondering if those taking this mood stabilizer for bipolar disorder may have increased neuroplasticity. Perhaps. Scientists have no idea yet.

Neuroplasticity and mental illness

Psychiatrists were also interested in this study, but for a completely different reason. Now they take a lot of time to eliminate the consequences of psychological trauma received by patients in early childhood.

Three quarters of all chronic psychiatric disorders occur before the age of 25, and half of these begin during adulthood.

At this time, a person is simultaneously at the stage of the greatest cerebral plasticity and at the peak of vulnerability to mental illness. The events of these years can affect not only the further behavior of a person, but also his DNA.

Scientists came to this conclusion after identifying a gene that increases the risk of developing schizophrenia, activating the destruction of connections between neurons Schizophrenia risk from complex variation of complement component 4.. As the body matures, weak or unnecessary connections between neurons are usually removed so that others can develop. Disruption of this process is most likely associated with the onset of many diseases, including Alzheimer's disease and autism.

Further examples were found during the observation of rats. These rodents and humans have surprisingly much in common when it comes to things like stress, anxiety, and attachment. In baby rats, differences in DNA and behavior were found depending on how the mothers looked after them (measured mainly by how often mothers licked their babies).

In the first week of life, the babies of less caring mothers were more fearful and more sensitive to stress, and their DNA contained more methyl groups that inhibit the process of gene expression. Scientists were able to reverse this effect by giving mature rats a substance called trichostatin, which blocks histone deacetylase Epigenetic programming by maternal behavior. … This removed some of the methyl groups from the DNA, and the nervous rats began to behave in the same way as the cubs of caring mothers.

This study gives hope that the negative impact of childhood experiences on gene expression can then be eliminated. This is great news because early childhood stress is a risk factor for many mental health conditions, including anxiety, mood disorders, and some personality disorders. A 2014 study of children who experienced abuse and children growing up under normal conditions found an association between depressive syndromes and methyl groups in the DNA Child Abuse, Depression, and Methylation in Genes Involved with Stress, Neural Plasticity, and Brain Circuitry. …

Summing up

Of course, all traumatic events cannot be completely eliminated from life, but these studies give hope that someday we will be able to reduce or even completely reverse the consequences of psychological trauma.

Nevertheless, there are negative aspects to the theory of the brain returning to a plastic state. It is not for nothing that our brains have a limited period of plasticity. Takao Hensch, a neuroscience professor at Harvard University, believes plasticity takes up a lot of energy. We will get very tired if all the neural circuits are constantly active. They may be contracted to protect the brain.

Moreover, we cannot be sure that the new period of neuroplasticity will not harm us. It may be easier for us to learn Chinese, but at the same time, we will more clearly remember all the disappointments and psychological trauma that we would prefer to forget about.

Finally, our entire identity is hidden in these neural circuits. Do we want to interfere with their work if there is a risk of changing our very essence?

However, it will be difficult to resist when the return of neuroplasticity to the brain promises to get rid of childhood psychological trauma and cure diseases such as Alzheimer's and autism.