Traumatic Memories, Part 1

Most of the time, most of us wish we could remember things better. But some of the time all of us have things we wish we could forget. Traumas, emotional upset, grief — all can be more than we can wish to bear.
     When anxiety becomes too intense and persistent, the level of stress becomes de-bilitating. There are many negative effects on the adrenal gland and its production of hormones that are designed to cope with stress. Beyond that, the brain is also affected. These effects are the hallmark of what is commonly called “Post-traumatic Stress Syndrome” (PTSD), which seems to be a common and growing problem with American soldiers returning from Iraq and Afghanistan. While older people are in the wrong age bracket to have this problem, they are very likely to know about PTSD in soldiers and may even have children or grandchildren who have PTSD.
     You don't have to be a combat soldier to develop anxiety disorders such as PTSD. Everyone has probably had some kind of traumatic experience that caused a serious emotional trauma. Such experiences are always associated with a host of cues, many subconscious, that are part of the original learned traumatic experience. The learned association may be remembered at some unconscious level long after the conscious memory is lost.
      Sensory cues, even if not recognized consciously, can trigger recall of disturbing memories or even just the negative emotions that went with the original bad event. Sometimes this is the basis for so-called “anxiety attacks,” which seem to come out of nowhere.
      Anxiety disorders are among the most common mental health problems and are often treated with so-called extinction therapies. That is, therapy is geared toward unlearning (extinguishing) our fears by deliberately re-living the disturbing event under safe conditions and thereby learning we can cope.      
Modern psychotherapy for phobias, anxiety, and PTSD often involves recalling the original bad event under reassuring conditions. But this has to be done with conscious re-assessment and realization that the original negative emotions and fear are no longer applicable because the re-living is a simulation in a safe environment. One creates a new learning substitute for the original emotional trauma.
      The re-living must include dealing with the negative emotions in the light of reason and new emotional experience. Therapy requires critical thinking about thoughts and feelings, especially those that are unhelpful and unrealistic. The patient is gently led to face memories anew and to learn new ways of thinking and behaving. This re-creation of the bad event allows us to extinguish memory of the original bad situation and its negative emotions.
      I recently got an up-date in this area of research at a seminar by Gregory Quick from the Department of Psychiatry at the University of Puerto Rico. As Pavlov showed, memory extinction is a basic phenomenon even in simple animals. If you repeatedly ring a bell and then stress a rat, it soon learns to become distressed the next time it hears that bell, even after you stop the stress. In the lab, this is manifested by the rat showing freeze behavior. But, if you repeat the bell enough times without the stress, the conditioned response (CR) (freeze behavior) eventually becomes extinguished.
     At first, scientists thought that extinction erases the memory of the CR. But extinction really creates a new memory that competes with memory of the original CR. Both memories co-exist. Over time the extinction memory may be lost, and the CR can return. The implication is that, just as ordinary learning needs rehearsal, so does extinction learning.
     Therapy for emotional trauma and PTSD might be more effective if therapy were approached like a conventional learning experience whose memory is affected in all the usual ways. Recall what was said about extinction being a case of new learning. Re-learning of an extinguished response occurs much more readily than it does for an initial extinction learning. This is an example of priming. It’s like re-learning a foreign language. It goes easier the second time and the memory might be even more dependable.
      Since memory of an emotional CR learning experience and its extinction can co-exist, these two memories compete for which one is strong enough to survive long-term. Sadly, the CR memory is often stronger. Cues are extremely important to both forming and retrieving all kinds of memory. It seems likely there are many more explicit cues for CR memories than for extinction memories. Therapy should be aimed at enriching the number and variety of cues associated with extinction learning. Rehearsal is likewise important. So far, nobody seems to have given that much thought.
     There is another aspect to emotional learning: learning to learn. If you have multiple anxieties, they may generalize and "spread" to facilitate learning new anxieties. The corollary would be that learning how to promote extinction could also generalize and thus increasing the general ability to cope with emotional trauma. Obviously, for one's brain to learn how to do that, one would need to begin with a single relatively easy extinction learning task.
    
     Dr. Bill Klemm is a Professor of Neuroscience at Texas A&M University. Visit his book site and blog at ThankYouBrain.com for more help on improving learning and memory. Copyright 2010, W. R. Klemm