There are certainly changes in the brain that happen with PTSD, but its not a traumatic brain injury....though it can cause brain damage more or less by making the brain function in a less effective manner. I guess in the end traumatic brain injuries and disorders like PTSD can both cause brain damage but not the exact same sort of damage if that makes sense....at least that is how I understood it in the abnormal psychology class I took before dropping out of college. Perhaps that therapist meant something more like that.

Getting proper treatment ASAP, decreases the risk of it getting to the point of brain damage....but untreated the changes it causes in the brain become more defined and
harder to treat. I would have liked to know that before I
decided to ignore it for a few years and hope it would go
away on its own.