Post-traumatic stress disorder is one of the major risk factors for veteran suicide. There has been some progress in treatment of this condition with the use of psychedelic medicines. However, this mental health condition is not completely understood. Recent research into the nature of traumatic memories may help. It turns out that traumatic memories tend to be stored in a different part of the brain than other memories. Thus they are experienced differently than normal memories.
Memories of Traumatic Events
The basic issue in PTSD is that memories cannot be controlled. They intrude themselves into normal everyday life. A veteran who has been out of the service for years or decades will find themselves suddenly back in a terrifying situation that, in reality, happened years before. These are flashbacks and are the way that PTSD never lets a person who experienced psychological trauma ever forget and move on. Military combat experiences are not the only things that create PTSD. Sexual assault and other types of trauma in civilian life cause similar symptoms. Researchers at Mount Sinai in New York and Yale University looked for an explanation for why this happens.
Brain Scans of Traumatic Memories
The researchers trying to understand PTSD memories did brain scans of 28 PTSD patients. The patients were scanned as they listened to narrations of their own memories. The recording included neutral, sad, and traumatic memories. When people listened to neutral or sad memories like the death of a member of their family the hippocampus in the brain became active and “lit up” on the scans. This is normal because the hippocampus is where the human brain contextualizes and organizes memories.
However, when PTSD patients listened to recordings of their traumatic memories such as military combat situations, terrorist attacks, sexual assaults, school shootings, etc. the hippocampus did not become active. The part of the brain that “lit up” was the part that considers current experiences and thoughts. It is the posterior cingulate cortex or P.C.C. for short. This part of the brain is typically used for internally directed thoughts such as daydreaming or introspection. The researchers found that people with more severe PTSD had a greater tendency for this area to be involved than in folks with less severe PTSD.
PTSD Memories Are Always Current
The point of this finding is that individuals who suffer from PTSD and get flashbacks experience them as current events and not memories. They really are back in the traumatic situation so far as their brain is concerned. When the PTSD is sufficiently severe the person’s traumatic memories crowd out current experience and replace it with trauma experienced years before. Sadly, that old trauma is forever new. This finding has implications for treatment of PTSD.
Exposing PTSD Patients to Their Traumatic Past
A basic approach to treating PTSD is to have patients talk about and reexperience their traumatic memories. The idea has been that this helps make the old, traumatic memory less painful. It has been thought to be sort of an exposure or desensitization therapy such as with phobias. Psychedelic medicines help in making psychotherapy more effective largely by reducing the anxiety that comes with reexperiencing those memories. The new evidence of PTSD memories being stored and processed differently than other memories is pertinent to this approach.
Should treatment professionals continue to have PTSD patients re-expose themselves to past trauma as a therapeutic tool? Techniques like EMDR or eye movement and reprocessing and desensitization during re-exposure to past trauma have been shown to be effective. The fact that traumatic memories are experienced as current experience tells us that this approach is on track. The rationale seems to be that one wants the PTSD patient to organize their traumatic memory and store it where it belongs in the hippocampus area of the brain. Once there the patient can experience this as a memory and not as a current threatening experience.
The key to this is enabling the person suffering from PTSD to be able to recognize past trauma for what it is and put it in context instead of always experiencing it new every day like a horror story version of the movie “Groundhog Day” in which the main character is made to relive every day until he learns a basic life lesson. The P.C.C. part of the brain works on determining the relevance of current experiences. Traumatic experiences need to be filed in the part of the brain responsible for memories in order for them to lose their power to constantly intrude into everyday life.