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The observable examined

PTSD – a speculation

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“Are you abandoning me? Have you given up on me?”. These were the questions my wife was asking me in my dreams, a week or two, prior to my planned recent travel abroad. No, my wife and I were not engaged in a bitter marital discord or about to break up. Rather, as I have catalogued elsewhere on this blog, my wife endured and fought a very painful battle with cancer before finally succumbing to it. That was almost three years ago. This dream highlights something important about our minds. It draws attention to the fact that although I have never felt it overtly, there is a lingering feeling of guilt that I could and should have done a lot more for her.  Then, of course, there are always undercurrents of hopelessness, and thoughts contemplating the fleeting nature of our existence not to mention inexplicable feelings of sadness, the onset of which could be triggered by a piece of music or a story in the news.  In short, existential angst amplified by looking at life through the lens of a departed individual who is of deep emotional significance to you. Left unchecked, these thoughts and feelings could create a positive feedback loop leading to a full blown depression, and complete withdrawal from society. The checking comes from a grieving process involving intense rationalization or cognitive effort and a constant readjustment of our worldview (could be rational or irrational) to accommodate these life shocks. In fact, most people are able to regain their bearings, given adequate time (note: the recovery period is not the same for everybody).  [ Fortunately for me, this experience has translated into a passion :  to help transform the practice of medicine and delivery of healthcare through innovative use of technology. That is now my singular focus.]

The Wall Street Journal published an article – Last Marine Standing : A Life Tormented by Survival.  It chronicles the life of Marine Lance Cpl. Williams post-Iraq. It is a very poignant article. It has been seven years since 11 members of his team were blown up in a roadside bomb. Cpl.Williams remains tormented by guilt, hopelessness, and other debilitating symptoms that  make it difficult for him to lead a “normal” life. The article offers some clues on how the Army psychiatrists are approaching the treatment of these individuals, as in the following excerpt:

“….The VA’s Dr. Maguen hasn’t met Lance Cpl. Williams. But she says his symptoms are typical of these more-complicated cases “where there are many different elements of moral injury and loss acting together, making it challenging for [the patient] to recover.”

Researchers are just beginning to study the prevalence of these  types of psychological injury among combat veterans and seek treatments to supplement PTSD therapies. In small-scale studies, researchers have found that about 30% of Marines and soldiers seeking treatment reported that moral-injury experiences were the incidents that most haunted them on their return from war.

In a pilot program with the Marines, clinicians used “adaptive disclosure” therapy to treat traumatic loss and moral injury. Patients held mock conversations with dead friends and imagined aloud how their buddies would respond.

The Pentagon has agreed to fund a larger-scale trial among Marines, according to psychologist Brett Litz of the Boston VA, who along with Dr. Maguen is a pioneer in the field. Dr. Maguen, meanwhile, is recruiting candidates for a VA study of treatment for troops troubled by having taken the lives of others…..”

Pioneers they may be, but I don’t think techniques like “adaptive closure” go far enough. Neither do the standard assortment of available drugs in the psychiatrist’s toolkit. As an alternative, I want to propose a cognitive neuroscience framework that may help illuminate the underlying mechanism and motivate approaches to treatments that may prove more effective.

Ever heard of Theory of Mind (ToM). If you have not, don’t worry. From Wikipedia,

Theory of mind is the ability to attribute mental states—beliefs, intents, desires, pretending, knowledge, etc.—to oneself and others and to understand that others have beliefs, desires, and intentions that are different from one’s own…”

We tap into this ability for everything, from buying a gift for our beloved to anticipating the reactions of our bosses when asking for a raise. In short, we have the ability to running simulations of imagined events and predict behaviors of the other actors in the scene. Wearing my scientific hat, I have always wondered whether grief intensely engages the ToM system (because emotional centers are also included)  in our brains. More specifically, I view a large portion of grieving as involving simulations in the brain taking the departed person’s point of view or reliving moments of joint interactions and anticipating how they may have  reacted emotionally (happy, angry, etc.,). “Moving on” is then an disengagement from the simulation behavior (or, at a minimum, significant blunting of the emotional components) specific to the departed individual(s). Disengagement is a function of intense rationalization, which I alluded to earlier.

I believe this can be extended to, at least, certain flavors of PTSD experienced by the veterans returning from war. In these individuals, it is the exaggerated response of the ToM system. In some sense, the systems engaged in “theory of mind” have gone awry. In the link below, is a very interesting conversation with the commander of a bomb diffusion unit.

http://www.npr.org/2012/07/09/156454241/the-life-that-follows-disarming-ieds-in-iraq

He mentions that in crowded places like airports, he is constantly looking at “who he needs to kill” to get to an exit, an example of “theory of mind” misfiring.

My prediction is Transcranial Magnetic Simulation knockout of  selective parts of the ToM system (particularly regions involved in emotions) would help provide relief (at least temporarily) for such individuals or those trapped in the local minima of “overuse of simulations”. The neural correlates of the ToM system are being actively studied by experts in the field and I am pretty sure what I noted above can be mapped onto actual brain sites for targeted therapies.

One of the hallmarks of PTSD is “stress”. Robert Sapolsky wrote a book called “Why Zebras Don’t Have Ulcers?”. The simple answer is, their stress levels are highest only when the predator is in sight. When this happens, they literally run for their life. If they survive, they go back to grazing. No more thinking about who is going to attack me next or what other danger should I worry about now. Out of sight, out of mind. But we on the other hand, have the brilliant twin abilities : running simulations and making predictions. One massive side-effect : grief and its really ugly cousin PTSD, witness Marine Lance Cpl. Williams.

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Written by asterix98

February 18, 2013 at 1:49 am

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