Exploring PTSD Symptom Dynamics: A Network Approach Using Dynamic Time Warping

NATO science for peace and security series. Sub-series E, Human and societal dynamics

Abstract

New perspectives on psychiatric disorders have emerged in recent years, calling for more precise and individualized approaches to mental health disorders. Network theory conceptualizes psychopathological symptoms as components of complex dynamic systems, in which symptoms interact with one another and with external factors in intricate and evolving patterns. The mapping of these systems potentially allows for the identification of monitoring and intervention targets. This chapter illustrates the Dynamic Time Warping (DTW) algorithm for constructing symptom networks, building on two recent studies on Post-Traumatic Stress Disorder (PTSD). The studies described in this chapter were based on a cohort of 55,632 Japan Ground Self-Defense Force personnel who were deployed in response to the 2011 Great East Japan Earthquake and completed the Impact of Event Scale-Revised annually from 2013 to 2018. The first study applied DTW to create symptom networks for individuals with significant PTSD symptoms (IES-R ≥ 25, n = 1,120). The second study analyzed dynamic symptom networks in four groups with distinct PTSD symptom severity trajectories (cumulative IES-R > 5, n = 10,211), allowing for the creation of temporal profiles reflecting the order symptom improvement and worsening. The first study identified four clusters of PTSD symptoms, yielding evidence for a new “Dissociation” cluster. In the second study, lower network density in undirected DTW analyses was associated with chronic PTSD. Directed analyses showed that dissociation symptoms decreased first during recovery, while emotional reactivity persisted. Conversely, in worsening PTSD avoidance symptoms escalated first, while dissociation symptoms intensified last. These findings demonstrate the potential of DTW as a tool for constructing interpretable networks that capture the complex dynamics of psychological processes. This approach could enhance our understanding of a wide range of mental health conditions. Future research should further explore its applications to enable more personalized and effective mental health interventions.

Authors 8

1. Florentine H. S. van der Does Aachen Department of Psychiatry, Leiden University Medical Center

   Leiden University Medical Center

   Affiliation as printed

   Department of Psychiatry, Leiden University Medical Center, Leiden, the Netherlands

2. Masanori Nagamine

   National Defense Medical College

   Affiliation as printed

   Division of Behavioral Science, National Defense Medical College Research Institute, Saitama, Japan

3. Masato Kitano

   National Defense Medical College

   Affiliation as printed

   Division of Behavioral Science, National Defense Medical College Research Institute, Saitama, Japan

4. Taku Saito

   National Defense Medical College

   Affiliation as printed

   Division of Behavioral Science, National Defense Medical College Research Institute, Saitama, Japan

5. Nic J. A. van der Wee Aachen Department of Psychiatry, Leiden University Medical Center

   Leiden University Medical Center

   Affiliation as printed

   Department of Psychiatry, Leiden University Medical Center, Leiden, the Netherlands

6. Eric H. G. J. M. Vermetten Aachen Department of Psychiatry, Leiden University Medical Center

   Leiden University Medical Center

   Affiliation as printed

   Department of Psychiatry, Leiden University Medical Center, Leiden, the Netherlands

7. Jun Shigemura

   Uniformed Services University of the Health Sciences · Mejiro University

   Affiliation as printed

   Department of Psychiatry, Uniformed Services University of the Health Sciences, Bethesda, USA

   Faculty of Health Sciences, Mejiro University, Saitama, Japan

8. Erik J. Giltay Aachen Health Campus The Hague

   Leiden University · University of Antwerp

   Affiliation as printed

   Collaborative Antwerp Psychiatric Research Institute (CAPRI), Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium

   Health Campus The Hague, Leiden University, The Hague, The Netherlands