Promising effects of treatment with flotation-REST (restricted environmental stimulation technique) as an intervention for generalized anxiety disorder (GAD): a randomized controlled pilot trial

A randomized controlled safety and feasibility trial of floatation-REST in anxious and depressed individuals

BACKGROUND

Reduced Environmental Stimulation Therapy via floatation (floatation-REST) is a behavioral intervention designed to attenuate exteroceptive sensory input to the nervous system. Prior studies in anxious and depressed individuals demonstrated that single sessions of floatation-REST are safe, well-tolerated, and associated with an acute anxiolytic and antidepressant effect that persists for over 48 hours. However, the feasibility of using floatation-REST as a repeated intervention in anxious and depressed populations has not been well-investigated.

METHODS

In this single-blind safety and feasibility trial, 75 individuals with anxiety and depression were randomized to complete six sessions of floatation-REST in different formats: pool-REST (weekly 1-hour float sessions), pool-REST preferred (float sessions with flexibility of duration and frequency), or an active comparator (chair-REST; weekly 1-hour sessions in a Zero Gravity chair). Feasibility (primary outcome) was assessed via an 80% rate of adherence to the assigned intervention; tolerability via study dropout and duration/frequency of REST utilization; and safety via incidence of adverse events and ratings about the effects of REST.

RESULTS

Of 1,715 individuals initially screened, 75 participants were ultimately randomized. Six-session adherence was 85% for pool-REST (mean, M = 5.1 sessions; standard deviation, SD = 1.8), 89% for pool-REST preferred (M = 5.3 sessions; SD = 1.6), and 74% for chair-REST (M = 4.4 sessions; SD = 2.5). Dropout rates at the end of the intervention did not differ significantly between the treatment conditions. Mean session durations were 53.0 minutes (SD = 12.3) for pool-REST, 75.4 minutes (SD = 29.4) for pool-REST preferred, and 58.4 minutes (SD = 4.3) for chair-REST. There were no serious adverse events associated with any intervention. Positive experiences were endorsed more commonly than negative ones and were also rated at higher levels of intensity.

CONCLUSIONS

Six sessions of floatation-REST appear feasible, well-tolerated, and safe in anxious and depressed individuals. Floatation-REST induces positively-valenced experiences with few negative effects. Larger randomized controlled trials evaluating markers of clinical efficacy are warranted.

CLINICAL TRIAL REGISTRATION IDENTIFIER

NCT03899090.

Induction of altered states of consciousness during Floatation-REST is associated with the dissolution of body boundaries and the distortion of subjective time

Floatation-REST (Reduced Environmental Stimulation Therapy) minimizes stimulation of the nervous system by immersing subjects in an environment without sound or light while they effortlessly float in thermoneutral water supersaturated with Epsom salt. Here we investigated the relationship between altered states of consciousness (ASC) and its association with the affective changes induced by Floatation-REST. Using a within-subject crossover design, 50 healthy subjects were randomized to 60 min of Floatation-REST or 60 min of Bed-REST (an active control condition that entailed lying supine on a warm waterbed in a dark and quiet room). Following Floatation-REST, subjects felt significantly more relaxed, less anxious, and less tired than after Bed-REST. Floatation-REST also induced significantly more pronounced ASC characterized by the dissolution of body boundaries and the distortion of subjective time. The loss of body boundaries mediated the loss of anxiety, revealing a novel mechanism by which Floatation-REST exerts its anxiolytic effect.

The impact of floatation therapy on body image and anxiety in anorexia nervosa: a randomised clinical efficacy trial

Background

Body image disturbance and anxiety are core features of anorexia nervosa (AN), a psychiatric disorder with one of the highest mortality rates. This study examined the efficacy of a novel non-pharmacological treatment, floatation-REST (Reduced Environmental Stimulation Therapy) on body image disturbance and anxiety in inpatients with AN.

Methods

This parallel group randomised controlled trial compared floatation-REST vs. care as usual in women and girls hospitalised for treatment of AN in Tulsa, Oklahoma, USA. Participants were randomised on a 2:1 ratio to receive eight, twice-weekly, 60-min floatation-REST sessions for 4 weeks, in addition to care as usual, or to receive care as usual. The primary outcome was the average change in body dissatisfaction from pre- to post-float as measured by the Photographic Figure Rating Scale. The secondary outcome was the average change in anxiety from pre- to post-float as measured by the state version of the State Trait Anxiety Inventory. Longitudinal effects of floatation-REST on body dissatisfaction were also examined. All analyses were conducted using the intention-to-treat principle. Planned linear mixed models tested the effect of floatation-REST vs. care as usual. The trial was preregistered (clinicaltrials.govNCT03610451).

Findings

Between March 16, 2018 and February 25, 2021, 133 participants were screened for eligibility, and 86 were consented. Eighteen were excluded after consent, for a final randomisation sample of 68 participants (45 floatation-REST; 23 care as usual). There were two session by condition interactions on body dissatisfaction (p = 0.00026) and state anxiety (p < 0.0001), such that the floatation-REST group exhibited acute (i.e., pre- to post-session) reductions in body dissatisfaction (floatation-REST group mean change (Δm) = -0.43; 95% CI -0.56 to -0.30, p < 0.0001, Cohen's d = 0.23), and acute reductions in anxiety (floatation-REST group Δm = -15.75; 95% CI -17.95 to -13.56, p < 0.0001, Cohen's d = 1.52); however, the care as usual group exhibited no significant changes. With regard to longitudinal results, there was a significant time by treatment interaction between baseline and immediately post intervention (p = 0.012) and baseline and six-month follow up (p = 0.0019). At immediately post intervention, there was a trending reduction in body dissatisfaction for the floatation-REST group (Δm = -0.41, 95% CI -0.86 to 0.03, p = 0.068) and care as usual group (Δm = 0.61; 95% CI -0.04 to 1.27, p = 0.070). At six-months post-intervention, the floatation-REST group exhibited lower body dissatisfaction (Δm = -0.91; 95% CI -1.37 to -0.45, p = 0.0020, Cohen's d = 0.53) whereas the care as usual group reported no change in body dissatisfaction (Δm = 0.35; 95% CI -0.28 to 0.98, p = 0.96) relative to baseline. There were no adverse events related to the trial during the study.

Interpretation

Our findings suggest that Floatation-REST decreased body dissatisfaction compared to care as usual acutely after each float session and at six-month follow-up. Floatation-REST has potential utility for the treatment of body image disturbance and anxiety in AN. These results may be limited by some generalisability concerns given the recruitment of a modest sample receiving inpatient treatment at a single site.

Funding

The William K. Warren Foundation.

Reduced Environmental Stimulation Therapy (REST) in anxiety and depression: An experience sampling study

Background

Reduced Environmental Stimulation Therapy (REST) is a behavioral intervention that systematically attenuates external sensory input to the nervous system. Previous studies have demonstrated acute anxiolytic and antidepressant effects of single sessions of REST in anxious individuals, however the duration and time course of these effects is unknown. In the current study, we used experience sampling and multiple sessions of REST to explore the time course of the anxiolytic and antidepressant effects over a 48-hour time period.

Methods

75 adults with anxiety and/or depression were randomized to complete 6 sessions of REST (either pool-REST, pool-REST preferred, or chair-REST). Post-REST effects were tracked using experience sampling on a smartphone with a ten-item survey administered at 6 time points for each session (i.e., immediately before and after REST and then 4, 8, 24, and 48 hours later). Using principal component analysis, responses to survey items at baseline were reduced to broad symptom clusters of anxiety, depression, and serenity and were utilized in linear mixed effects models to determine the magnitude and time course of post-REST effects.

Results

REST was associated with significant decreases in anxiety and depression, and significant increases in serenity, with effects lasting for 48 hours. Repeated exposure to REST was associated with lower baseline levels of anxiety at later sessions.

Conclusion

These initial findings suggest that the anxiolytic and antidepressant effects of REST persist for at least two days, and that repeated REST sessions may have additive effects on lowering anxiety-related symptoms. These findings could help to determine the optimal intervention frequency of REST and facilitate future investigations focused on the combination of REST with standard treatments for anxiety and depression.

Effect of Psychosocial Interventions for Individuals Who Underwent Arthroscopy in Femoroacetabular Impingement: A Randomized Controlled Trial

PURPOSE

The purpose of this protocol was to discover the connection between patients with non-surgical pain or other discomfort and their psychosocial status. Cognitive behavior therapy will be used, which we verified will determine the effect and feasibility of postoperative rehabilitation processes.

MATERIALS AND METHODS

This study will include 200 patients ranging from 18 to 60 years old who have underwent or will undergo FAI arthroscopy in the West China Hospital Sports Medicine Center from 2023 to 2026. A standardized prospective single-center parallel-group randomized controlled trial will be used for these participants. The participants will be divided into intervention (telephone versus face-to-face versus music versus floatation) and control groups. The follow-up periods will be measured pre-operatively, as well as postoperatively at 1, 3, and 6 months. The primary outcomes will include the modified Harris Hip Score (mHHS) and the Visual Analogic Score (VAS), and the secondary outcomes will include the range of motion (ROM), the Huaxi Emotional-distress Index (HEI), and the depression, anxiety, and stress scale (DASS-21 scale). Furthermore, the Patient Health Questionnaire-9 (PHQ-9) and a Short-Form 12 (SF-12) questionnaire will also be evaluated.

DISCUSSION

This study will evaluate the clinical and cost-effectiveness of different types of psychosocial-therapy-based rehabilitation methods designed to improve the quality of life of FAI patients with persistent symptoms.

The role of non-ordinary states of consciousness occasioned by mind-body practices in mental health illness

BACKGROUND

Research with hallucinogens suggests that non-ordinary states of consciousness (NOSCs), particularly mystical-type experiences, predict improvements in various affective disorders and substance use disorders (SUDs). Little is known, however, about the therapeutic potential of NOSCs induced by mind-body practices such as meditation, yoga and breathwork.

METHODS

We conducted a literature review in online databases (PubMed, Scopus, Google Scholar) and preprint databases (SSRN, bioRxiv) to identify studies of NOSCs induced by mind-body practices and their effects in affective disorders and SUDs.

RESULTS

A wide variety of mind-body practices involving physical movement (i.e., shamanic drumming, yoga) and hyper-focused immersive mental experiences (i.e., meditation, breathwork) have been reported in the literature. Preliminary evidence, mostly from qualitative studies and open label studies, suggest that mind-body practices produce NOSCs. Such experiences have been associated with short-term reduced levels of anxiety and depression, increased motivation to quit addictive behaviors, and enhanced self-awareness and spiritual well-being.

LIMITATIONS

Findings are limited by the scarcity of literature in this field. Further rigorous and methodologically sound empirical research is needed, including comparative studies of NOSCs occasioned by different methods.

CONCLUSIONS

Mind-body practices may represent a promising approach for treating mental health disorders. The NOSCs induced by such practices may lead to beneficial shifts in perceptions, values, beliefs, and behaviors. Given the challenges with hallucinogen-based therapies, mind-body practices may represent a more accessible and acceptable way of eliciting potentially helpful NOSCs in clinical practice.

Flotation Restricted Environmental Stimulation Therapy for Chronic Pain: A Randomized Clinical Trial

IMPORTANCE

Flotation restricted environmental stimulation therapy (REST) is an emerging therapeutic intervention that, to our knowledge, has never been directly compared with an indistinguishable placebo in patients with chronic pain.

OBJECTIVE

To determine whether 5 flotation-REST sessions alleviate chronic pain.

DESIGN, SETTING, AND PARTICIPANTS

This single-blind, randomized clinical trial compared flotation-REST as an intervention for the treatment of chronic pain with indistinguishable placebo and wait-list control conditions at Hannover Medical School, Hannover, Germany. Men and women aged 18 to 75 years who had been diagnosed with chronic pain disorder with psychological and somatic factors (International Statistical Classification of Diseases and Related Health Problems, 10th Revision, German Modification, code F45.41) by physicians at the study center were randomly assigned to 1 of the 3 groups. Data were collected from June 26, 2018, to June 18, 2020.

INTERVENTIONS

Patients in the intervention and placebo groups underwent 5 treatment sessions lasting 60 to 90 minutes, each session separated by 4 days. The placebo treatment was delivered in the same floating tank but controlled for effortless floating and environmental stimulus restriction. Patients in the wait-list control group did not receive any additional treatment but were asked to continue any ongoing treatments at the time of enrollment.

MAIN OUTCOMES AND MEASURES

The primary outcome was a change in pain intensity 1 week after the last treatment session. The assessment was repeated at 12 and 24 weeks. Secondary outcomes included pain-related disability, pain area, pain widespreadness (number of body regions affected by pain), anxiety, depression, and quality of life, as well as several other short-term outcomes.

RESULTS

A total of 99 patients (mean [SD] age, 51.7 [12.3] years; 80 women [81%]) were included in the study. No differences were found among the groups in the primary outcomes (mean [SD] change in maximum pain: -7.6 [19.7] for the intervention group, -5.8 [12.7] for the placebo group, and 0.4 [14.0] for the wait-list control group; mean [SD] change in mean pain: -2.1 [19.4] for the intervention group,-4.2 [16.2] for the placebo group, and 2.0 [12.6] for the wait-list control group). Long-term secondary outcomes did not show significant differences. In the short term, patients in the intervention group showed significant improvements in pain intensity (-17.0 [17.1]; P < .001), relaxation (23.9 [22.6]; P < .001), anxiety (-10.1 [8.4]; P < .001), pain area (-3.6% [7.4%]; P < .001), and widespreadness (-2.0 [3.0]; P < .001), and similar changes where observed in the placebo group.

CONCLUSIONS AND RELEVANCE

Patients with chronic pain experienced no long-term benefits from the 5 flotation-REST interventions. Clinically relevant short-term changes in pain in the placebo group suggest that improvements may not be caused by environmental stimulus restriction or effortless floating as previously thought.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03584750.

Reduced Environmental Stimulation in Anorexia Nervosa: An Early-Phase Clinical Trial

Reduced Environmental Stimulation Therapy (REST) alters the balance of sensory input to the nervous system by systematically attenuating sensory signals from visual, auditory, thermal, tactile, vestibular, and proprioceptive channels. Previous research from our group has shown that REST via floatation acutely reduces anxiety and blood pressure (BP) while simultaneously heightening interoceptive awareness in clinically anxious populations. Anorexia nervosa (AN) is an eating disorder characterized by elevated anxiety, distorted body representation, and abnormal interoception, raising the question of whether REST might positively impact these symptoms. However, this approach has never been studied in eating disorders, and it is unknown whether exposure to floatation REST might worsen AN symptoms. To examine these possibilities, we conducted an open-label study to investigate the safety and tolerability of REST in AN. We also explored the acute impact of REST on BP, affective symptoms, body image disturbance, and interoception. Twenty-one partially weight-restored AN outpatients completed a protocol involving four sequential sessions of REST: reclining in a zero-gravity chair, floating in an open pool, and two sessions of floating in an enclosed pool. All sessions were 90 min, approximately 1 week apart. We measured orthostatic BP before and immediately after each session (primary outcome), in addition to collecting BP readings every 10 min during the session using a wireless waterproof system as a secondary outcome measure. Each participant's affective state, awareness of interoceptive sensations, and body image were assessed before and after every session (exploratory outcomes). There was no evidence of orthostatic hypotension following floating, and no adverse events (primary outcome). Secondary analyses revealed that REST induced statistically significant reductions in BP (p < 0.001; Cohen's d, 0.2-0.5), anxiety (p < 0.001; Cohen's d, >1) and negative affect (p < 0.01; Cohen's d, >0.5), heightened awareness of cardiorespiratory (p < 0.01; Cohen's d, 0.2-0.5) but not gastrointestinal sensations, and reduced body image dissatisfaction (p < 0.001; Cohen's d, >0.5). The findings from this initial trial suggest that individuals with AN can safely tolerate the physical effects of REST via floatation. Future randomized controlled trials will need to investigate whether these initial observations of improved anxiety, interoception, and body image disturbance occur in acutely ill AN populations.

Clinical Trial Registration

ClinicalTrials.gov; Identifier: NCT02801084 (April 01, 2016).

An Active Inference Approach to Interoceptive Psychopathology

Interoception refers to the process by which the nervous system senses and integrates signals originating from within the body, providing a momentary mapping of the body's internal landscape and its relationship to the outside world. Active inference is based on the premise that afferent sensory input to the brain is constantly shaped and modified by prior expectations. In this review we propose that interoceptive psychopathology results from two primary interoceptive dysfunctions: First, individuals have abnormally strong expectations of the situations that elicit bodily change (i.e., hyperprecise priors), and second, they have great difficulty adjusting these expectations when the environment changes (i.e., context rigidity). Here we discuss how these dysfunctions potentially manifest in mental illness and how interventions aimed at altering interoceptive processing can help the brain create a more realistic model of its internal state.

Flotation REST as a Stress Reduction Method: The Effects on Anxiety, Muscle Tension, and Performance

The purpose of the study was to investigate the influence of flotation REST upon skilled and less skilled golfers’ anxiety in terms of physiological indicators of stress, self-rated anxiety scores, muscle tension, and the effect on golf putting. Prior to performing the putting task participants underwent a treatment of flotation REST or a period of resting in an armchair. Participants completed both treatments in a randomized order with a two-week interval. The results showed that both flotation REST and the armchair treatment reduced systolic blood pressure and heart rate, with no differences between treatments or athlete skill levels. No significant differences between treatments were revealed regarding self-ratings, level of muscle tension or putting precision. The results indicate that flotation REST may be useful for reducing negative symptoms related to stress and anxiety in general; however, no support for direct positive effects on golf performance were found.

The Elicitation of Relaxation and Interoceptive Awareness Using Floatation Therapy in Individuals With High Anxiety Sensitivity

BACKGROUND

Floatation-REST (Reduced Environmental Stimulation Therapy), an intervention that attenuates exteroceptive sensory input to the nervous system, has recently been found to reduce state anxiety across a diverse clinical sample with high levels of anxiety sensitivity (AS). To further examine this anxiolytic effect, the present study investigated the affective and physiological changes induced by Floatation-REST and assessed whether individuals with high AS experienced any alterations in their awareness for interoceptive sensation while immersed in an environment lacking exteroceptive sensation.

METHODS

Using a within-subject crossover design, 31 participants with high AS were randomly assigned to undergo a 90-minute session of Floatation-REST or an exteroceptive comparison condition. Measures of self-reported affect and interoceptive awareness were collected before and after each session, and blood pressure was measured during each session.

RESULTS

Relative to the comparison condition, Floatation-REST generated a significant anxiolytic effect characterized by reductions in state anxiety and muscle tension and increases in feelings of relaxation and serenity (p < .001 for all variables). Significant blood pressure reductions were evident throughout the float session and reached the lowest point during the diastole phase (average reduction >12 mm Hg). The float environment also significantly enhanced awareness and attention for cardiorespiratory sensations.

CONCLUSIONS

Floatation-REST induced a state of relaxation and heightened interoceptive awareness in a clinical sample with high AS. The paradoxical nature of the anxiolytic effect in this sample is discussed in relation to Wolpe’s theory of reciprocal inhibition and the regulation of distress via sustained attention to present moment visceral sensations such as the breath.

Complementary and Alternative Medicine Treatments for Generalized Anxiety Disorder: Systematic Review and Meta-analysis of Randomized Controlled Trials

INTRODUCTION

The objective was to evaluate efficacy/safety of complementary and alternative medicine (CAM) methods for generalized anxiety disorder (GAD) based on randomized controlled trials in adults.

METHODS

Data sources. Six electronic databases ("generalized anxiety (disorder)" and "randomized trial") and reference lists of identified publications were searched to March 2017.

STUDY SELECTION

Eligibility: full-text publications (English, German language); CAM versus conventional treatment, placebo/sham or no treatment; GAD diagnosed according to standard criteria; and a validated scale for disease severity. Of the 6693 screened records, 32 were included (18 on biologically-based therapies, exclusively herbal preparations; eight on manipulative and body-based therapies; and three on alternative medical systems and three on mind-body therapies).

DATA EXTRACTION

Cochrane Collaboration methodology was used for quality assessment and data extraction.

RESULTS

Direct comparisons of Kava Kava (Piper methysticum) extracts to placebo (4 quality trials, n = 233) were highly heterogeneous. Network meta-regression reduced heterogeneity and suggested a modest Kava effect [end-of-treatment Hamilton Anxiety scale score difference adjusted for baseline scores and trial duration: - 3.24 (95% CI - 6.65, 0.17; P = 0.059), Kava Kava 4 arms, n = 139; placebo 5 arms, n = 359]. Lavender (Lavandula angustifolia) extract (1 quality trial, 10 weeks, n = 523) and a combination of extracts of C. oxycantha, E. californica and magnesium (1 quality trial, 12 weeks, n = 264) were superior to placebo and balneotherapy was superior to paroxetine (1 quality trial, 8 weeks, n = 237) indicating efficacy. All other trials were small and/or of modest/low quality and/or lacked assay sensitivity. Safety reporting was poor.

CONCLUSION

Evidence about efficacy/safety of most CAM methods in GAD is limited. Apparent efficacy of certain herbal preparations and body-based therapies requires further confirmation.

Examining the short-term anxiolytic and antidepressant effect of Floatation-REST

Floatation-REST (Reduced Environmental Stimulation Therapy) reduces sensory input to the nervous system through the act of floating supine in a pool of water saturated with Epsom salt. The float experience is calibrated so that sensory signals from visual, auditory, olfactory, gustatory, thermal, tactile, vestibular, gravitational and proprioceptive channels are minimized, as is most movement and speech. This open-label study aimed to examine whether Floatation-REST would attenuate symptoms of anxiety, stress, and depression in a clinical sample. Fifty participants were recruited across a spectrum of anxiety and stress-related disorders (posttraumatic stress, generalized anxiety, panic, agoraphobia, and social anxiety), most (n = 46) with comorbid unipolar depression. Measures of self-reported affect were collected immediately before and after a 1-hour float session, with the primary outcome measure being the pre- to post-float change score on the Spielberger State Anxiety Inventory. Irrespective of diagnosis, Floatation-REST substantially reduced state anxiety (estimated Cohen’s d > 2). Moreover, participants reported significant reductions in stress, muscle tension, pain, depression and negative affect, accompanied by a significant improvement in mood characterized by increases in serenity, relaxation, happiness and overall well-being (p < .0001 for all variables). In reference to a group of 30 non-anxious participants, the effects were found to be more robust in the anxious sample and approaching non-anxious levels during the post-float period. Further analysis revealed that the most severely anxious participants reported the largest effects. Overall, the procedure was well-tolerated, with no major safety concerns stemming from this single session. The findings from this initial study need to be replicated in larger controlled trials, but suggest that Floatation-REST may be a promising technique for transiently reducing the suffering in those with anxiety and depression.

Trial registration: ClinicalTrials.gov NCT03051074

Comparison of Bispectral Index™ values during the flotation restricted environmental stimulation technique and results for stage I sleep: a prospective pilot investigation

Objective

To determine whether Bispectral Index™ values obtained during flotation-restricted environment stimulation technique have a similar profile in a single observation compared to literature-derived results found during sleep and other relaxation-induction interventions.

Results

Bispectral Index™ values were as follows: awake-state, 96.6; float session-1, 84.3; float session-2, 82.3; relaxation-induction, 82.8; stage I sleep, 86.0; stage II sleep, 66.2; and stages III–IV sleep, 45.1. Awake-state values differed from float session-1 (%difference 12.7%; Cohen’s d = 3.6) and float session-2 (%difference 14.8%; Cohen’s d = 4.6). Relaxation-induction values were similar to float session-1 (%difference 1.8%; Cohen’s d = 0.3) and float session-2 (%difference 0.5%; Cohen’s d = 0.1). Stage I sleep values were similar to float session-1 (%difference 1.9%; Cohen’s d = 0.4) and float session-2 (%difference 4.3%; Cohen’s d = 1.0). Stage II sleep values differed from float session-1 (%difference 21.5%; Cohen’s d = 4.3) and float session-2 (%difference 19.6%; Cohen’s d = 4.0). Stages III–IV sleep values differed from float session-1 (%difference 46.5%; Cohen’s d = 5.6) and float session-2 (%difference 45.2%; Cohen’s d = 5.4). Bispectral Index™ values during flotation were comparable to those found in stage I sleep and nadir values described with other relaxation-induction techniques.

Electronic supplementary material

The online version of this article (10.1186/s13104-017-2947-4) contains supplementary material, which is available to authorized users.