Memory Research News in Problems

Transcendental Meditation has dramatic benefits for those with PTSD

  • A month of practicing Transcendental Meditation daily resulted in 80% of military veterans with PTSD having their symptoms reduced to below the clinical level.

A pilot study involving 41 military veterans and 5 active-duty soldiers diagnosed with clinical levels of PTSD has found that one month of transcendental meditation produced dramatic benefits, with 37 (80%) having their symptoms reduced to below the clinical level, and 40 having a clinically significant decrease of more than 10 points.

A test 90 days later also showed that PTSD symptoms continued to improve, and a further three individuals had dropped to below the clinical level.

The participants learned the standard Transcendental Meditation technique, which is practiced 20 minutes twice a day. Those who practiced twice a day had greater benefits than those who practiced once a day.

The study follows on from two earlier studies involving Congolese refugees, who found a significant benefit after just 10 days of Transcendental Meditation.

Note that this is only a preliminary study, with no controls, and the participants were self-selected, responding to media advertising (89 responded — only those with clinical levels of PTSD were included in the study). However, the results certainly appear dramatic, and previous research has shown that Transcendental Meditation has a positive benefit for many of the conditions associated with PTSD, such as high anxiety, insomnia, depression, and high blood pressure.

https://www.eurekalert.org/pub_releases/2018-01/muom-vwl011018.php

Full text of the paper is available at https://academic.oup.com/milmed/article/183/1-2/e144/4781643

Reference: 

[4315] Herron RE, Rees B. The Transcendental Meditation Program’s Impact on the Symptoms of Post-traumatic Stress Disorder of Veterans: An Uncontrolled Pilot Study. Military Medicine [Internet]. 2018 ;183(1-2):e144 - e150. Available from: https://academic.oup.com/milmed/article/183/1-2/e144/4781643

Sleep helps process traumatic experiences

  • A finding that sleeping after watching a trauma event reduced emotional distress and traumatic memories is intriguing in light of the theory that PTSD occurs through a failure of contextual processing.

A laboratory study has found that sleeping after watching a trauma event reduced emotional distress and memories related to traumatic events. The laboratory study involved 65 women being shown a neutral and a traumatic video. Typically, recurring memories of certain images haunted the test subjects for a few days (these were recorded in detail in a diary). Some participants slept in the lab for a night after the video, while the other group remained awake.

Those who slept after the film had fewer and less distressing recurring emotional memories than those who were awake. This effect was particularly evident after several days.

 One of the reasons for this benefit is thought to be that the memory consolidation processes that happen during sleep help contextualize the memories. This is interesting in view of the recent theory that PTSD is associated with a deficit in contextual processing.

However, I'd note that there is conflicting evidence about the effects of sleep on negative memories (for example, see http://www.memory-key.com/research/news/sleep-preserves-your-feelings-about-traumatic-events).

https://www.eurekalert.org/pub_releases/2016-12/uoz-shp121316.php

Reference: 

[4314] Kleim B, Wysokowsky J, Schmid N, Seifritz E, Rasch B. Effects of Sleep after Experimental Trauma on Intrusive Emotional Memories. Sleep [Internet]. 2016 ;39(12):2125 - 2132. Available from: https://academic.oup.com/sleep/article/39/12/2125/2706348

Individual cognitive processing therapy had better PTSD improvement

  • A large randomized study has found that cognitive processing therapy works better when administered on an individual basis, but that regardless, it is only successful about half the time.

A randomized clinical trial of 268 active-duty personnel seeking treatment for PTSD has found that individual sessions of cognitive processing therapy were twice as effective as group sessions.

Participants were assigned to CPT in either 90-minute group sessions or 60-minute individual sessions twice weekly for six weeks. PTSD severity was reduced significantly more in those receiving individual treatment, however improvements were maintained during the six-month follow-up in both groups. Depression and suicidal ideation also improved equally with both forms of CPT.

However, even among those receiving individual CPT, some 50% still had PTSD and clinically significant symptoms.

https://www.eurekalert.org/pub_releases/2016-11/tjnj-icp112116.php

Full paper available at https://jamanetwork.com/journals/jamapsychiatry/fullarticle/2587076

Reference: 

[4313] Resick PA, Wachen JSchuster, Dondanville KA, Pruiksma KE, Yarvis JS, Peterson AL, Mintz J, Consortium andthe STRONG, Borah EV, Brundige A, et al. Effect of Group vs Individual Cognitive Processing Therapy in Active-Duty Military Seeking Treatment for Posttraumatic Stress Disorder: A Randomized Clinical Trial. JAMA Psychiatry [Internet]. 2017 ;74(1):28. Available from: http://archpsyc.jamanetwork.com/article.aspx?doi=10.1001/jamapsychiatry.2016.2729

Brain changes seen in veterans with PTSD after mindfulness training

  • A small study found mindfulness training had an observable effect on the brains of PTSD sufferers.

A pilot study involving 23 military veterans with PTSD found that those who received mindfulness training showed reduced PTSD symptoms, and brain changes that suggest a greater ability to shift and control attention. Mindfulness training was given to 14 veterans, while the other 9 received ‘control’ group support. Both groups were given brain scans before and after the treatment program.

The initial scan showed that, even during rest, veterans’ brains showed unusual activity in regions involved in responding to threats and other external dangers. After practising mindfulness, the default mode network was not only more active, but also showed stronger connections with the executive network, which is involved in controlling attention. PTSD is associated with reduced executive functioning.

Moreover, veterans responded well to the training, with more of that group sticking with the therapy, compared with the comparison psychotherapy group.

The researchers emphasize, however, that people with PTSD interested in this should seek out providers trained specifically in PTSD care, as mindfulness sessions can sometimes trigger symptoms such as intrusive thoughts to flare up.

http://www.eurekalert.org/pub_releases/2016-04/uomh-bcs033016.php

Reference: 

[4310] King AP, Block SR, Sripada RK, Rauch S, Giardino N, Favorite T, Angstadt M, Kessler D, Welsh R, Liberzon I. Altered Default Mode Network (dmn) Resting State Functional Connectivity Following a Mindfulness-Based Exposure Therapy for Posttraumatic Stress Disorder (ptsd) in Combat Veterans of Afghanistan and Iraq. Depression and Anxiety [Internet]. 2016 ;33(4):289 - 299. Available from: http://onlinelibrary.wiley.com/doi/10.1002/da.22481/abstract

Is PTSD a failure of context processing?

  • A new theory suggests a single dysfunction, in the processing of context, could underlie the multiple symptoms and characteristics of PTSD.

An interesting new theory for PTSD suggests that the root of the problem lies in context processing problems.

Context processing allows people and animals to recognize that a particular stimulus may require different responses depending on the context in which it is encountered. So, for example, a lion in the zoo evokes a different response than one encountered in your backyard.

Context processing involves the hippocampus, and its connections to the prefrontal cortex and the amygdala. Research has shown that activity in these brain areas is disrupted in those with PTSD.

The idea that a disruption in this circuit can interfere with context processing can explain most of the symptoms and much of the biology of PTSD. Previous models have focused on one aspect of the disorder:

  • on abnormal fear learning, which is rooted in the amygdala
  • on exaggerated threat detection, which is rooted in a network involving the amygdala, the anterior cingulate cortex and insula
  • on executive function and emotion regulation, which is mainly rooted in the prefrontal cortex.

The researchers suggest that a deficit in context processing would lead PTSD patients to feel "unmoored" from the world around them, unable to shape their responses to fit their current contexts. Instead, their brains impose an "internalized context", one that always expects danger.

This type of deficit, arising from a combination of genes and life experiences, may create vulnerability to PTSD in the first place.

The researchers are now testing their model.

https://www.eurekalert.org/pub_releases/2016-10/uomh-wrg100716.php

Reference: 

[4311] Liberzon I, Abelson JL. Context Processing and the Neurobiology of Post-Traumatic Stress Disorder. Neuron [Internet]. 2016 ;92(1):14 - 30. Available from: http://www.cell.com/neuron/abstract/S0896-6273(16)30640-7

Size of hippocampus associated with PTSD therapy benefits

  • Size of that key memory region, the hippocampus, appears to be not simply a risk factor for PTSD, but also key to whether sufferers will respond positively to exposure therapy.

Following previous research showing that having a smaller hippocampus is associated with increased risk of PTSD, a study involving 40 participants with PTSD and 36 trauma-exposed healthy controls has found that those PTSD patients who responded to the treatment had larger hippocampi compared to those who didn’t benefit from the therapy.

The participants were evaluated at baseline and after 10 weeks, during which time the PTSD group had prolonged exposure therapy.

The study found that both the resilient controls and the 23 patients with PTSD who responded to treatment had greater hippocampal volume at the beginning of the study than the 17 non-responders.

The findings add to growing evidence that the hippocampus is key to distinguishing between cues that signal safety and those that signal threat.

http://www.eurekalert.org/pub_releases/2016-05/cumc-sob051216.php

Reference: 

[4312] Rubin M, Shvil E, Papini S, Chhetry BT, Helpman L, Markowitz JC, J. Mann J, Neria Y. Greater hippocampal volume is associated with PTSD treatment response. Psychiatry Research: Neuroimaging [Internet]. 2016 ;252:36 - 39. Available from: http://www.sciencedirect.com/science/article/pii/S0925492715301451