Original Research ARTICLE
Cognitive Flexibility Predicts PTSD Symptoms: Observational and Interventional Studies
- 1Sagol Brain Institute Tel-Aviv, Wohl Institute for Advanced Imaging, Tel Aviv Sourasky Medical Center, Israel
- 2Department of Emergency Medicine, Tel Aviv Sourasky Medical Center, Israel
- 3Sagol School of Neuroscience, Tel Aviv University, Israel
- 4Trauma Unit and Department of Cardiothoracic Surgery, Shaare Zedek Medical Center, Israel
- 5Psychological Trauma Care Center, Shaare Zedek Medical Center, Israel
- 6School of Psychological Sciences, The Gershon Gordon Faculty of Social Sciences, Tel Aviv University, Israel
- 7Department of Psychology, University of Haifa, Israel
- 8Department of Psychiatry and Behavioral Sciences, School of Medicine, Stanford University, United States
- 9Faculty of Medicine, Hebrew University of Jerusalem, Israel
- 10Institute of Pain Medicine, Department of Anesthesiology and Critical Care Medicine, Tel Aviv Sourasky Medical Center, Israel
- 11Sackler Faculty of Medicine, Tel Aviv University, Israel
- 12Pain Management & Neuromodulation Centre, Guy's and St Thomas' NHS Foundation Trust, United Kingdom
- 13Department of Psychiatry, University of Michigan, United States
- 14Department of Psychiatry, Langone Medical Center, New York University, United States
Introduction: Post-Traumatic Stress Disorder (PTSD) is a common and severe psychiatric disorder with profound public health impact due to its high prevalence and debilitating nature. The first period after trauma exposure is a critical period to evaluate individuals at risk of prolonged PTSD. Neurobehavioral dimensions of the response to trauma exposure may help identify survivors at high risk, as well as developing novel, mechanism-based early interventions. We hypothesized that better neurocognitive functions one month after trauma would predict less severe PTSD symptoms a year post trauma exposure, and that early neurobehavioral intervention would improve neurocognitive domains, later to be evident in clinical amelioration.
Methods: To longitudinally evaluate neurocognitive and clinical dimensions of responses to traumatic events and to uncover underlying cognitive mechanisms of clinical symptoms, we used two large independent samples. In the first observational sample, we prospectively tracked clinical symptoms and cognitive functioning in 181 trauma-exposed individuals admitted to an hospital Emergency Room (ER), at one-, six-, and fourteen months following trauma exposure (‘Study 1’). In the second interventional sample, we longitudinally followed 87 recent trauma survivors, randomly allocated to either web-based neurocognitive training (n=50), which included classic paradigms used in cognitive neuroscience and executive function batteries, or control tasks (n=37). Similarly, we evaluated participants’ clinical condition and neurocognitive functions at one- and three months after trauma exposure (pre-and post-intervention), and at six-month after trauma admission, using an identical recruitment and evaluation methodology (‘Study 2’).
Results: Consistent with our main hypothesis, individuals with higher cognitive flexibility scores one-month after trauma showed significantly less severe PTSD symptoms at 14 months post-trauma (p=0.002). Consistent with our auxiliary hypothesis, improvement in cognitive flexibility following the intervention was significantly higher than improvement in control groups (p=0.019), and was associated with reduced PTSD symptoms at six-months post-trauma (p=0.017). Furthermore, the magnitude of improvement in cognitive flexibility post-intervention was significantly positively correlated with the subsequent clinical improvement (p=0.002).
Discussion: Our findings suggest that cognitive flexibility assessed post-trauma predicts PTSD symptoms in the first critical year, and demonstrates the effectiveness of early cognitive intervention. These findings may guide personalized mechanism-driven early interventions for acute PTSD individuals.
Keywords: Post-Traumatic Stress Disorder (PTSD), neurocognitive functioning, cognitive flexibility, Resilience factors, Risk factors, Cognitive training intervention
Received: 22 May 2018;
Accepted: 11 Sep 2018.
Edited by:Jutta Lindert, University of Applied Sciences Emden Leer, Germany
Reviewed by:Andres R. Schneeberger, Albert Einstein College of Medicine, United States
Lawrence T Lam, University of Technology Sydney, Australia
Copyright: © 2018 Ben-Zion, Fine, Keynan, Admon, Green, Halevi, Fonzo, Achituv, Merin, Sharon, Halpern, Liberzon, Etkin, Hendler and Shalev. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Mr. Ziv Ben-Zion, Tel Aviv Sourasky Medical Center, Sagol Brain Institute Tel-Aviv, Wohl Institute for Advanced Imaging, Tel Aviv, Israel, email@example.com