Distinguishing between rumination and intrusive memories in PTSD using a wearable self-tracking instrument: A proof-of-concept case study

Rumination has been shown to play a part in post-traumatic stress disorder (PTSD), but its relation to the intrusions characteristic of PTSD has mainly been investigated experimentally. This proof-of-concept case study explored the occurrence, personal experiences, and possible relation between rumination and intrusions in two PTSD patients in their daily living using a mixed method approach.

A novel wearable self-tracking instrument was employed which provided fine-grained temporal resolution of observation data and could eliminate recall bias. Furthermore, quantitative and qualitative data were collected on participants' symptoms, rumination and experiences of using the self-tracking instrument.

First, without distinguishing between the two phenomena, the participants tracked both for a week. After receiving psychoeducational training for distinguishing between rumination and intrusions, the differentiated phenomena were tracked for a week. Both participants reported being subjectively able to distinguish between rumination and intrusions and made observations with high adherence during the project.

Data hinted at a possible temporal relation between the phenomena in line with theories posing rumination as a maladaptive coping strategy as well as an exacerbator of PTSD symptoms. However, relations to mood were inconclusive. Furthermore, by using the self-tracking instrument, participants gained a heightened awareness of the characteristics of rumination and intrusions and contextual cues for occurrence, as well as a greater sense of momentary agency.

Results reveal promising prospects in using the wearable self-tracking instrument for further investigation of the relation between rumination and intrusions in the lived lives of PTSD patients, as well as potential for incorporating this method in clinical treatment. Key learning aims (1) Self-tracking with the One Button Tracker is a novel symptom registration method, particularly suited for use in psychotherapeutic treatment and research. (2) Rumination and intrusions appear to the participants as distinct cognitive phenomena and treatment targets in PTSD. (3) Registering rumination and intrusions in real-time could reveal important temporal relations between them and the contexts in which they occur. (4) The data obtained with this self-tracking method can potentially be used as a tool in, and for the further development of psychotherapy for PTSD.