Wearable Emotion Prosthetics for Post Traumatic Stress Disorder
Condition: Health Behavior
MeSH terms: Stress Disorders, Traumatic; Stress Disorders, Post-Traumatic
Study type: Interventional

Summary: 
      Involuntary stress reactions including hyper-reactivity and dissociation are key diagnostic
      features of many psychiatric disorders, are difficult to treat, and predict poor outcomes in
      conventional and neurobehavioral interventions. Here, we evaluate the extent to which a novel
      intervention, Tuned Vibroacoustic Stimulation (TVS), capitalizing on a preserved
      neurocircuitry for sympathetic and parasympathetic system activity can be used to modify
      arousal responses, overriding otherwise prepotent negative stress reactions.

      PTSD has been characterized by dysregulated responses to stress as a result of severe acute
      or chronic trauma resulting in significantly impaired functioning, quality of life, and
      morbidity/mortality. Physiologically, PTSD severity has been associated with elevated
      sympathetic tone and low heart rate variability suggesting that parasympathetic tone is
      suppressed. Lower heart rate variability specifically, as a measure of parasympathetic tone,
      is closely associated with impaired performance and resilience. In our first study (in
      review), we showed that in some individuals, TVS is associated with increased heart rate
      variability and performance under stress along with reduced subjective stress. These results
      suggest that TVS could provide some therapeutic benefit in PTSD.

      N=100 individuals with mild-moderate PTSD (as assessed by PCL-5/CAP5), at least half of which
      are military Veterans, will be assessed physiologically during active interventions.
      Mechanisms of attentional focus on cognitive and emotional stimuli will be assessed.
      Participants will also have a real-world intervention to determine if TVS helps alleviate
      stress, symptoms, and medication burden in the real world when stress has been identified.
      Success will suggest a new intervention pathway for a traditionally treatment-resistant
      dimension of psychopathology.
    

Detailed description: 
      This protocol will examine and elucidate a mechanistic model for tuned vibroacoustic
      stimulation (TVS), an exteroceptive cue that has been shown to reduce subjective and
      physiological indicators of stress and increase behavioral performance in healthy subjects.
      In this study, we will test whether TVS can reduce subjective and physiological signs of
      stress, improve performance, alleviate symptoms, and reduce medication burden in adults with
      post-traumatic stress disorder (PTSD). This protocol will also examine whether software that
      cues TVS in response to biological stress markers helps users detect, regulate, and develop
      long-term resilience to stress outside of the laboratory.

      Aim 1: Examine how TVS alters calmness and stress markers. Our overall hypothesis is that
      TVS, in combination with some other task, increases performance on that task by decreasing
      stress and increasing emotion regulation.

      Hypothesis 1: TVS during an attention task will lead to decreased GSR, increased HRV, and
      increases in prefrontal gamma and theta band EEG, along with improved behavioral performance
      on a focused attention, working memory and emotional information processing task. TVS will
      also reduce subjective stress levels.

      Aim 2: Examine the extent to which software, which monitors real time biological stress
      markers of users, and in response, automatically signals wearable hardware to deliver TVS
      when user is stressed, will be able to help users detect, regulate, and develop long-term
      resilience to stress outside the laboratory for two weeks.

      Hypothesis 2.1: Evaluate whether subjects with PTSD in the real world will use our software
      to detect and alert them of stress dynamically and if this is associated with stress
      regulation.

      Hypothesis 2.2: Examine whether TVS is associated with stress regulation. Hypothesis 2.3:
      Examine whether TVS is associated with reduction in PTSD symptoms and, possibly, medication
      burden.

      Over 39 million Americans suffer from excessive chronic stress, which can be psychologically
      and physically debilitating (Salleh, 2008). Untreated chronic stress plays a role in the
      development of major illnesses such as cardiovascular disease, obesity, anxiety and
      depression (Dallman et al., 2006; Swaab, Bao, & Lucassen, 2005). Post-traumatic stress
      disorder (PTSD), is a severe mental illness that impacts millions of veterans and civilians
      nationwide. Existing treatments for chronic stress and PTSD are often ineffective, have
      adverse effects, and are prohibited by cost, time-commitment, and accessibility, resulting in
      high rates of substance abuse and suicide (Jonas et al., 2013; Watts et al., 2013). Stress in
      general, and PTSD more specifically, are characterized by hyper-reactivity in the sympathetic
      nervous system which is associated with increased arousal and vigilance, and compromised
      reactivity of the parasympathetic nervous system, which helps to regulate emotion and stress
      responses (Kibler, Tursich, Ma, Malcolm, & Greenbarg, 2014; Lehrer & Gevirtz, 2014).

      PTSD has been characterized by dysregulated responses to stress as a result of severe acute
      or chronic trauma resulting in significantly impaired functioning, quality of life, and
      morbidity/mortality. Physiologically, PTSD severity has been associated with elevated
      sympathetic tone and low heart rate variability suggesting that parasympathetic tone is
      suppressed. HRV is widely used as a biomarker for the coordinated activity of the sympathetic
      and parasympathetic nervous symptom. A calmer, less stressful state is typically marked by
      increased HRV, likely attributed to respiration based parasympathetic stimulation (Grossman &
      Taylor, 2007). GSR is also a reliable index for sweat gland activity and changes in
      activation level of the sympathetic nervous system, and GSR usually increases with higher
      levels of stress (Mohan, Sharma, & Bijlani, 2011). EEG changes, such as elevated prefrontal
      gamma and theta, have also been associated with state of relaxed alertness. Our initial data
      (submitted) suggest that for some individuals, TVS can boost heart rate variability and
      performance under stress while reducing subjective stress. These results suggest that TVS
      could provide some therapeutic benefit in PTSD.

      Large scientific literature supports the role of vibration in regulating stress physiology
      (Takahashi, Ohashi, & Yokoyama, 2011; M. Uchikune, 2002; M. Uchikune, 2004). For example,
      slow whole-body vibration, in the 0.01 to 0.3 Hz range, is associated with increased ratings
      of pleasantness and increased parasympathetic tone (M. Uchikune, 2002; M. Uchikune, 2004).
      Stimulation at about 100 Hz has been shown to activate the posterior insula (Coghill et al.,
      1994) which is associated with increased attention to interoception, as promoted in many
      meditative traditions. Transcutaneous targets for the vibration frequencies have also been
      identified, including stellate ganglion and vagus nerve (Cipriano et al., 2014; Fang et al.,
      2016).

      In this study, we will be testing the potential for TVS to increase well-being (subjective
      calmness, increased performance, and physiological reactivity) in the PTSD population.
      Positive results would suggest that reduction in symptomatology may be possible without
      effort, and in lieu of specific interventions with medications or psychotherapy. A wearable
      form of TVS technology will be examined in a real-world setting. We will use ambulatory
      assessment to detect physiological indications of stress unique to each user and to provide
      user-optimized TVS, examining whether it increases parasympathetic nervous system reactivity
      in response to stress, thus decreasing subjective stress just as a user's stress begins to
      increase.
    

Intervention name(s): Tuned Vibroacoustic Stimulation (TVS); no active intervention
Intervention type(s): Other; Other
Intervention description(s): TVS is an exteroceptive cue that may reduce subjective and physiological indicators of stress and increase behavioral performance; No intervention will be administered
Allocation: Randomized
Intervention model: Factorial Assignment
Intervention model description: randomized, controlled factorial within subject design
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Basic Science
Keywords: PTSD