Stress-related illnesses, such as post-traumatic stress disorder, trigger changes in brain structure, including differences in the volume of gray matter versus white matter, as well as the size and connectivity of the amygdala.
These long-term changes might explain why young people who are exposed to chronic stress early in life are prone to mental problems such as anxiety and mood disorders later in life, as well as learning difficulties.
The “stress hormone” cortisol can create a domino effect that hardwires pathways between the hippocampus and amygdala in a way that causes the brain to be predisposed to a constant state of fight-or-flight.
Chronic stress can also trigger stem cells to malfunction. When this happens they inhibit connections to the prefrontal cortex, which would improve learning and memory, but lays down durable scaffolding linked to anxiety, depression, and post-traumatic stress disorder.
Thankfully, mindset, behaviour and chronic stress are never fixed. Neuroplasticity makes it possible to change brain structure and function across its lifespan, meaning the conscious changes can improve the structure and connectivity of the brain.