New hope for PTSD, anxiety and depression
The effects of stress on the brain have been known for awhile, but the "why" behind it has been stumping neuroscientists.
While they've known that hormones can change the way nerves fire, which leaves us open to PTSD, depression and anxiety, the cellular level has been more difficult to study.
But neuroscientists at UC Berkeley have (somewhat accidentally) figured out that the stress hormone corticosterone (the rat's version of human cortisol) "trips a switch" in the brain's stem cells, triggering them to produce too many oligodendrocytes. Oligodendrocytes are the cells that coat the axons with a protective sheath.
Under normal conditions, this is a good thing because the coating protects and insulates the axons. It helps babies as they mature and helps prevent developmental disorders and addiction.
But overproduction can be bad. One example they give is soldiers. Better sheathing can strengthen the connection between the hippocampus and the amydgdala, which enhances a soldier's fight or flight response. Good in a war zone, bad at home.
While moderate stress is fine, prolonged stress can work against the brain to cause or worsen PTSD, anxiety and depression.
So where's the good news? This is a great discovery. It may lead to drugs that can decrease the overproduction of those oligodendrocytes. Until recently, no one even knew this overproduction was happening.
Here's what I read: