For a long time now, scientists have been aware of a link between chronic stress and developing mental illness in later life. Now, a new study has tracked the physical changes in parts of the brain that occur due to chronic stress, giving insight into just why stress might create mental health issues and pointing to how we might prevent this from happening.
The research, carried out by a team at the University of California, Berkeley, and published in the journal Molecular Psychiatry, has shown that chronic stress actually causes physiological changes in the brain.
It’s long been known that people with stress-related illnesses, like post-traumatic stress disorder (PTSD), exhibit very particular changes in different brain regions. In particular, in the amount of gray matter versus white matter they have. However, until now the reasons behind this have remained a mystery.
In a series of experiments, the UC Berkeley team were able to track how chronic stress causes the production of more myelin-producing cells, which would increase the white matter in some areas of the brain. Due to the fact that white matter functions to create connections in the brain, this research suggests that the overproduction of myelin-creating cells might disrupt the fine balance the brain needs for timing the communications between different regions.
“We studied only one part of the brain, the hippocampus, but our findings could provide insight into how white matter is changing in conditions such as schizophrenia, autism, depression, suicide, ADHD and PTSD,” Daniela Kaufer, UC Berkeley associate professor of integrative biology and lead researcher in this study, is quoted as saying.
To explain how this increased connectivity might affect people and cause mental health problems, Kaufer uses the example of people with PTSD, which is an anxiety disorder that can be crippling in its severity. It is perhaps most commonly associated with former military personnel.
Kaufer hypothesizes that the traumatic events the sufferer has endured increase the number of connections between regions of the brain like the hippocampus, which regulates memory and emotion, with regions like the amygdala, which is at least partially responsible for the so-called “fight or flight” response. In turn, this would lead to difficulties regulating things like anxiety, especially when other regions of the brain that might moderate our responses have fewer of those same connections. This, Kaufer says, leads to an emotional response that is out of proportion with the reality of the situation, producing uncontrollable panic responses.
To be clear, this research is ongoing and the hypothesis needs to be subjected to widespread human tests, but the basic science behind it appears sound. As well as testing this particular line of thought, the researchers also want to look at chronic stress and what physiological impact early life trauma has on later developing mental health problems. That’s because various research has already found a connection between trauma in childhood and later developing mental health issues.
The research also emphasizes the possible advantages of early intervention so that chronic stress-induced changes in the brain are minimized and the fallout, particularly in young children, can be managed. In turn, it is hoped that early intervention strategies might prevent people developing mood disorders in later life, though this remains a subject of study.
All in all, the research has been welcomed as an important small step into gaining insight into what might be happening at the smallest physiological levels in our brains and how the body reacts to chronic stress, and its potential for helping us understand the complexity of mood and anxiety disorders is encouraging for anyone who, like myself, must deal with a mental health problem.
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