It is well known that many violent adults have a history of psychological trauma in childhood. Nevertheless, a direct link between early trauma and neurological changes has been difficult to find, until now. Researchers have now shown that mental trauma in childhood creates lasting brain changes. 

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This writes Science Daily  

 

Childhood trauma changes the brain 

In the January 15 issue of the journal Translationtal Psychiatry, Professor Carmen Sandi and colleagues demonstrate for the first time a connection between psychological trauma in young rats and neurological changes similar to those found in violent people.

This research shows that people are exposed to trauma in childhood not only suffer psychologically, but their brains also change, Sandi explains.





He is the head of EPFL's Laboratory for Behavioral Genetics, Director of the Brain Mind Institute, and a member of the National Centers of Excellence in Research SYNAPSY.

This adds an extra dimension to the consequences of abuse, and obviously has scientific, therapeutic and social implications. 





 

Trauma leads to impaired control over aggressive impulses

The researchers therefore believed that the traumatic experiences at a young age had left traces in the brains of the rats they examined.

In a challenging social situation, the orbitofrontal cortex of a healthy person is activated to inhibit aggressive impulses and to maintain normal interaction, Sandi explains.  

However, in the rats we studied, we noticed that there was very little activation of the orbitofrontal cortex. This in turn reduces their ability to regulate their own aggressive impulses. This decreased activation is accompanied by overactivation of the amygdala, a region of the brain involved in emotional reactions.  

Other researchers who have studied the brains of violent human individuals have observed similarly reduced orbitofrontal activation and reduced inhibition of aggressive impulses. But such observed brain changes have not previously been studied against trauma.

 

Traumatic stress alters genes that are specifically linked to aggression

The researchers also saw changes in how certain genes in the brain were expressed. They focused on genes that are known to be involved in aggressive behavior, and where it is known that certain variants of the gene predispose the person to have an aggressive behavior. They looked at whether psychological stress experienced by rats caused a change in the expression of these genes.

We found that level off The MAOA gene increased in prefrontal cortex, says Sandi.

This change was related to an epigenetic change, in other words, the traumatic experience ended up causing a long-term change in the expression of this gene. The experiment therefore emphasizes that Stress can help create lasting genetic changes.

  

Antidepressants curbed aggression

Since aggressive behavior is associated with increased MAOA genetic expression in the specific genes linked to aggression, the researchers also wanted to investigate the extent to which it was possible to reverse / attenuate this form of genetic expression of the specific genes.

In other words, the researchers were looking for an MAOA gene inhibitor.

In their study, they used antidepressants drugs to see if this could reverse the increase in aggression in rats that had experienced mental stress while they were young. And in fact, this had the desired effect.

Going forward, researchers will explore treatments for reversing physical changes in the brain, and try to shed light on whether some people are more vulnerable to being affected by trauma based on their genetic makeup.

This research can also provide increased knowledge about the possible effects of antidepressants - an ability that is increasingly believed to be able to renew the brain's plasticity, says Sandi.

 

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