Wearable monitoring devices are an innovative way to measure heart rate (HR) and heart rate variability (HRV), however, there is still debate about the validity of these wearables. This study aimed to validate the accuracy and predictive value of the Empatica E4 wristband against the VU University Ambulatory Monitoring System (VU-AMS) in a clinical population of traumatized adolescents in residential care. A sample of 345 recordings of both the Empatica E4 wristband and the VU-AMS was derived from a feasibility study that included fifteen participants. They wore both devices during two experimental testing and twelve intervention sessions. We used correlations, cross-correlations, Mann-Whitney tests, difference factors, Bland-Altman plots, and Limits of Agreement to evaluate differences in outcomes between devices. Significant correlations were found between Empatica E4 and VU-AMS recordings for HR, SDNN, RMSSD, and HF recordings. There was a significant difference between the devices for all parameters but HR, although effect sizes were small for SDNN, LF, and HF. For all parameters but RMSSD, testing outcomes of the two devices led to the same conclusions regarding significance. The Empatica E4 wristband provides a new opportunity to measure HRV in an unobtrusive way. Results of this study indicate the potential of the Empatica E4 as a practical and valid tool for research on HR and HRV under non-movement conditions. While more research needs to be conducted, this study could be considered as a first step to support the use of HRV recordings provided by wearables.

Background: Many adolescents in residential care have been exposed to prolonged traumatic experiences such as violence, neglect, or abuse. Consequently, they suffer from posttraumatic stress. This not only negatively affects psychological and behavioral outcomes (eg, increased anxiety, depression, and aggression) but also has adverse effects on physiological outcomes, in particular on their neurobiological stress systems. Although current evidence-based treatment options are effective, they have their limitations. An alternative to traditional trauma treatment is meditation-based treatment that focuses on stress regulation and relaxation. Muse is a game-based meditation intervention that makes use of adolescents’ intrinsic motivation. The neurofeedback element reinforces relaxation abilities.
Objective: This paper describes the protocol for a randomized controlled trial in which the goal is to examine the effectiveness of Muse (InteraXon Inc) in reducing posttraumatic stress and normalizing neurobiological stress systems in a sample of traumatized adolescents in residential care.
Methods: This will be a multicenter, multi-informant, and multimethod randomized controlled trial. Participants will be adolescents (N=80), aged 10 to 18 years, with clinical levels of posttraumatic symptoms, who are randomized to receive either the Muse therapy sessions and treatment as usual (intervention) or treatment as usual alone (control). Data will be collected at 3 measurement instances: pretest (T1), posttest (T2), and at 2-month follow-up. Primary outcomes will be posttraumatic symptoms (self-report and mentor report) and stress (self-report) at posttest. Secondary outcomes will be neurobiological stress parameters under both resting and acute stress conditions, and anxiety, depression, and aggression at posttest. Secondary outcomes also include all measures at 2-month follow-up: posttraumatic symptoms, stress, anxiety, depression aggression, and neurobiological resting parameters.
Results: The medical-ethical committee Arnhem-Nijmegen (NL58674.091.16) approved the trial on November 15, 2017. The study was registered on December 2, 2017. Participant enrollment started in January 2018, and the results of the study are expected to be published in spring or summer 2021.
Conclusions: Study results will demonstrate whether game-based meditation therapy improves posttraumatic stress and neurobiological stress systems, and whether it is more effective than treatment as usual alone for traumatized adolescents.
Trial Registration: Netherlands Trial Register NL6689 (NTR6859); https://www.trialregister.nl/trial/6689

Aim Many youth in residential care suffer from post-traumatic symptoms that have adverse effects on a range of psychological, behavioural and physiological outcomes. Although current evidence-based treatment options are effective, they have their limitations. Meditation interventions are an alternative to traditional trauma-focused treatment. This pilot study aimed to evaluate three game-based meditation interventions in a sample of traumatized youth in residential care. Methods Fifteen participants were randomly divided over three conditions (Muse, DayDream and Wild Divine) that all consisted of twelve 15-minute game-play sessions. Physiological measurements (heart rate variability) were conducted at baseline, post-treatment and during each intervention session. Post-traumatic symptoms, stress, depression, anxiety and aggression were assessed at baseline, post-treatment and 1-month follow-up. Results Physiological stress regulation was improved during the meditation sessions of all three interventions. User evaluations were in particular high for Muse with a rating of 8.42 out of 10 for game evaluation. Overall, outcomes on psychopathology demonstrated the most robust effect on stress. Muse performed best, with all participants showing reliable improvements (reliable change indexes [RCIs]) in post-traumatic symptoms, stress and anxiety. Participants who played Daydream or Wild Divine showed inconsistent progression: some participants improved, whereas others remained stable or even deteriorated based on their RCIs. Conclusions Preliminary findings show promising outcomes on physiology, psychopathology and user evaluations. All indicate the potential of this innovative form of stress regulation intervention, and the potential of Muse in particular, although findings should be considered preliminary due to our small sample size. Further studies are warranted to assess intervention effectiveness effects of Muse or other game-based meditation interventions for traumatized youth.

Many adolescents in residential care have experienced traumatic events and suffer from posttraumatic stress. Prolonged activation of neurobiological stress systems as the autonomic nervous system (ANS) and the hypothalamic-pituitary-adrenal (HPA) axis can result in long-lasting maladaptive alternations. This study investigated the effectiveness of Muse, a game-based meditation intervention, on the sympathetic nervous system (SNS), parasympathetic nervous system (PNS), and cortisol basal activity and reactivity to acute stress among adolescents with posttraumatic symptoms in residential care. The intervention consisted of two gameplay sessions a week, for 6 consecutive weeks. Seventy-seven adolescents with clinical levels of posttraumatic symptoms (10–18 years old) received either Muse as an addition to treatment as usual (n = 40) or treatment as usual alone (n = 37). We expected reduced basal activity for the SNS and cortisol and increased basal activity for the PNS. As for the response to acute stress, we expected decreased PNS and increased HPA axis reactivity. The Muse group exhibited lower basal activity for the SNS and increased HPA reactivity to acute stress. There were no differences between conditions on SNS and HPA axis activity during rest and on SNS and PNS reactivity to acute stress. Game-based meditation therapy is a promising intervention for the treatment of adolescents with posttraumatic symptoms in residential care. Implications for clinical relevance and trauma-focused treatment purposes are discussed.

Alterations in neurobiological stress systems such as the autonomic nervous system (ANS) and hypothalamic-pituitary-adrenal (HPA) axis contribute to the development and maintenance of psychological and behavioral problems after traumatic experiences. Investigating neurobiological parameters and how these relate to each other may provide insight into the complex mechanisms at play. Whereas the preponderance of studies focuses on either the ANS or the HPA axis separately, the current study is the first to evaluate relations between posttraumatic stress and both basal activity during rest and stress reactivity of the ANS as well as the HPA axis in a sample of traumatized adolescents and healthy controls. The traumatized sample (n = 77), based on clinical levels of posttraumatic stress, was a convenience sample that was recruited within residential institutions, was compared to a healthy control sample (n = 48) recruited within the general community. For the ANS, we expected increased SNS and decreased PNS activity during rest and increased SNS and decreased PNS reactivity to social stress among traumatized adolescents compared to healthy controls. Regarding the HPA axis, we expected increased basal cortisol levels and decreased cortisol reactivity to stress in the traumatized sample. Compared to healthy controls, traumatized adolescents exhibited significantly higher sympathetic and lower parasympathetic activation during rest and increased sympathetic reactivity to acute stress (ANS parameters). Outcomes on the HPA axis (i.e. cortisol) indicated that traumatized adolescents showed increased cortisol levels during rest and blunted cortisol reactivity to acute stress. Implications for clinical relevance and trauma-focused treatment purposes are discussed.