We have known for some time that chronic stress is not good for our physical or mental health. Along with various negative effects on physical health, people who live with chronic stress are at an increased likelihood of developing mental illnesses such as depression or anxiety disorders.
Although we have seen the effect of stress on health outcomes, until recently we have had little understanding about how exactly the stress impacts our brains to make them more susceptible to illness.
New research out of the University of California Berkeley has finally shed some light on this topic. These new findings have shown chronic stress generates long-term changes to the brain.
Doctors already knew of brain abnormalities present among individuals with conditions such as post-traumatic stress disorder (PTSD). These involved differences in the amount of grey and white matter in the brain.
Without going into too much detail here, grey matter is mostly neurons and white is composed of axons (appearing white because of the myelin sheath surrounding them). Myelin speeds the connectivity between cells.
Researchers in these studies examined only the hippocampus of the brain (an area known to be important in the regulation of emotions and involved in several psychiatric conditions).
Findings in rodent studies indicated that chronic stress generates more myelin-producing cells and fewer neurons than normal. This leads to more white matter and changes the way the brain’s cells communicate with one another.
These researchers also found chronic stress to cause changes in stem cells in the hippocampus—stress changing the cells to mature into white matter cells rather than neurons as they would in normal circumstances.
If brain matter is changed and causes different areas of the brain to connect with one another too much and others not enough, it is not too difficult to imagine how this could lead to various symptoms.
This research is still in early days. Preliminary results are interesting though and now studies are underway to test this hypothesis in people with PTSD and other conditions.
The hope is to get more information and try to gain a better understanding of exactly how all of these elements interact with one another.
Along with greater understanding, we may be able to develop new ways to protect people from the harmful effects of chronic stress or to prevent these changes in the brain from occurring and thus prevent later mental illness.
For now, we can try to reduce stress as much as possible and speak to a doctor if symptoms such as anxiety or depression are interfering with life.