Traumatic events and stress in childhood can affect the brain into adulthood, scientists have shown, marking for the first time specific changes in major brain structures in the amygdala and hippocampus.
Through magnetic resonance imaging (MRI) scans of 35 adults diagnosed with major depressive disorder (MDD) and 35 healthy controls, cross-referenced with questionnaires, the new research found a link between the magnitude of cloud tension and traumatic stress of childhood.
Negative experiences and early life abuse are known to be risk factors for developing mental health disorders such as MDD, and the team behind this new study believes that changes in brain function may be one of the reasons.
“Now that we can really identify which specific subdivisions of the amygdala or hippocampus are permanently altered by events of childhood abuse, trauma or mistreatment, we can begin to focus on how you can mitigate those changes or even reverse them, “says Peter Silverstone, a professor of psychiatry at the University of Alberta in Canada.
Recent advances in MRI scanning technology have meant that these specific areas of the brain could be studied in detail in living human volunteers, building on previous research looking at the link between weight and brain size in animals.
The amygdala and hippocampus are of particular interest to scientists studying the development of childhood as they continue to grow and develop for a long time after birth – they are associated with learning, memory , and the management of emotions, fears and stress.
The researchers suggest that damage done in the early years of life of the brain – and the amygdala and hippocampus in particular – could make it more vulnerable to stresses that occur later in adult life. .
“Although we did not find any significant effects of MDD or long-term antidepressant treatment on the amygdala subnuclei, we found that childhood hypertension had adverse effects on both hippocampal and amygdala nerves,” the researchers report. in their published paper.
The more we know about how stress and trauma affect the brain, and the specific structures and regions it contains, the better we can design treatments to try to prevent or control it. disorders – it is possible to focus on essential therapies.
The focus of the study on childhood trauma within those with depression leaves ample room for further study. Research is needed to separate the effects of depression itself, including inherited factors, from the effects of anxiety.
The hippocampus has long been thought to be the part of the brain most at risk from the destructive effects of physical and emotional stress, although much more remains to be done to fully understand these relationships. total.
With depression one of the leading causes of disability worldwide, affecting as many as 1 in 10 people at some point, better ways to manage and treat depression could rely on studies like this one.
“This could help to shed some light on how promising new therapies such as psychedelics work, as there is augmenting evidence that they could lead to an increase in zero regeneration in these areas. , “said Silverstone.
“Understanding the specific structural and neurochemical brain changes that underlie mental health disorders is a critical step toward developing potential new treatments for the conditions. that has not increased since the onset of COVID-19 epidemic. “
The research was published in the Journal of Psychiatry & Neuroscience.