Stress and stress-related disorders are responsible for a significant amount of disability worldwide. Although the term “stress” is used in a wide variety of contexts, it has consistently been demonstrated that individuals with high levels of stress experience impaired physical and mental functioning with more work days lost and a greater utilization of health care services 1. The total estimated number of people living with anxiety disorders in the world is 264 million 2. The Agency for Healthcare Research and Quality found that, in 2006, $57.5 billion was spent on mental health care in the Unites States 2. Excessive stress is a common complaint in modernized countries, which negatively affects quality of life. Chronic stress has a negative effect on multiple brain functions, causing impairment of many executive skills, including working memory, decision making and attentional control 3. Excessive stress can also cause physical symptoms, including headaches, insomnia, reduced immune function, and pain. Previous work has demonstrated that repeated social and physical stressors are associated with changes in the amygdala that often results in clear social avoidance 4. In the clinical setting, the TSST is a valid and reliable method for inducing stress in a human subject 567. It induces stress by requiring participants to make an interview-style presentation, followed by a surprise mental arithmetic test, in front of an interview panel who do not provide feedback or encouragement 5. The TSST was employed in this study to induce a stress response to a socially evaluative situation. The period of induced stress lasted approximately 15 minutes and was divided into 5-minute components.

There are many and varied treatments for stress and anxiety, which can be divided into pharmacologic and non-pharmacologic methods. Pharmacotherapies for stress and anxiety, such as selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs), have the most evidence to support their usage 8, but are plagued with side effects such as sexual dysfunction and sleep disturbance 9. Techniques for reducing stress and anxiety by non-pharmacological methods can potentially make a great impact on quality of life and stress-related morbidity. Multiple previous studies have shown that techniques utilizing biofeedback, neurofeedback and noninvasive brain stimulation are effective in mitigating stress and anxiety. One non-pharmacologic approach for altering how the brain manages stress and anxiety is through a non-invasive somatosensory-based therapy called eye movement desensitization and reprocessing (EMDR). EMDR is a psychotherapy treatment originally designed to alleviate the distress associated with traumatic memories 10. Bilateral stimulation is a core element of EMDR and involves a stimulus (visual, auditory or tactile) which occur in a rhythmic, alternating left-right pattern, such as watching a hand or moving light alternating from left to right or listening to tones that alternate between the left and right ears.

Multiple previous studies have demonstrated a positive therapeutic benefit of EMDR on individuals with high or pathological levels of anxiety or stress 11. Several clinical trials have also shown positive effects of EMDR in adults with autism spectrum disorder 12, depression 1314, and post-traumatic stress disorder 1516. In addition, techniques, such as EMDR and bilateral alternating somatosensory stimulation, do not have adverse drug interactions or side effects 17. In this study, bilateral alternating somatosensory stimulation was administered using TouchPoints™ 18. TouchPoints™ are wearable, non-invasive EMDR-based devices to relieve stress using a patent-pending technology called BLAST (bilateral alternating stimulation in tactile form) and have been shown to have a clinical effect on the human stress response. The therapeutic effect of TouchPoints™ is thought to involve reduction of electrical activity in the salience network, which can be measured on EEG 181920. Previous work has demonstrated a statistically significant reduction in subjective stress levels in as little as 30 seconds using Touch Points™ 18. However, these studies were not based on controlled experimental conditions and were not blinded.

The purpose of this randomized placebo-controlled triple-blind study is to more precisely and quantitatively evaluate the effects of BLAST, applied using TouchPoints™, on subjects with stress and anxiety induced by the TSST, a clinically validated technique for reliably inducing stress in human subject 567. The level of stress and anxiety was assessed both subjectively and objectively through the subject’s subjective rating of emotional stress and the salivary cortisol levels, respectively, sampled at multiple time points before and after the TSST.

Eighty healthy, male subjects were recruited and completed all procedures with no dropouts. The average age of 26.21 years ( 5.38 years). Table 1 lists the group mean and standard deviation (SD) for each of the chosen metrics (subjective stress rating (0-10 scale); salivary cortisol level) evaluated at each of the three time points in this study: baseline (prior to start of TSST); immediately following completion of TSST; after 20 minutes of rest following completion of TSST. There were no statistically significant group differences in the baseline (initial) measurements for either metric.

However, the results showed that the application of BLAST using TouchPoints™ significantly decreased the subject’s subjective stress level, when evaluated immediately following the completion of the TSST and after 20 minutes of rest following the completion of the TSST (Figure 1).

Results of the salivary cortisol levels did not reveal any statistically significant difference between the two groups (p > 0.05) at the initial time point. However, analysis of the change in salivary cortisol levels revealed that the subjects in the treatment group had a statistically significant difference in salivary cortisol levels immediately following the completion of the TSST, and at 20 minutes following the completion of the TSST, as compared to placebo (Figure 2).

In this study, our results showed that treatment with bilateral alternating somatosensory stimulation resulted in a statistically significant reduction in both subjective and quantitative metrics of stress and anxiety, as compared to placebo, assessed in subjects undergoing the TSST both immediately following the completion of the test and after 20 minutes of rest following the completion of the test. This suggests that this technique was effectively reducing stress during the active portion of the TSST and that this effect persisted following the TSST. This agrees with previous work which supports a role for bilateral alternating somatosensory information and EMDR in attenuating the stress response and returning stress induced reactions back to baseline. The statistically significant reduction in subjective stress ratings following treatment with BLAST agrees with a previous study by our group showing significant reductions in subjective ratings of both physical and psychological stress following 30 seconds of treatment with BLAST as compared to their baseline 18. It also supports several studies which have shown a beneficial effect of EMDR-based treatment on patients with high levels of anxiety 131527. The significant reduction in salivary cortisol levels in the treatment group as compared to the control group also is consistent with these results but, as a more quantitative and objective metric of the stress response 22, provides a novel and compelling additional support for the benefit of BLAST in attenuating the stress response. As with the subjective stress ratings in these subjects, there were no statistically significant differences between the two groups at the initial assessment. However, there was a statistically significant (p < 0.05) difference seen immediately following the TSST and after a twenty-minute rest following the TSST, when compared to the placebo group (p < 0.0001). A graph comparing the time course of the salivary cortisol levels between the two groups revealed a noticeable downward trending of the salivary cortisol levels in the treatment group that was not present in the controls. This may indicate a beneficial effect of bilateral alternating somatosensory stimulation in stabilizing cortisol levels and returning subjects to a normal baseline after a stress-induced response 22.

Although the current study provided more rigorous experimental conditions and statistical power than our group’s previous retrospective study showing the effect of BLAST on attenuating the stress response, there still were limitations. Specifically, this study included only males which, although it avoided the effects of the menstrual cycle and oral contraceptives on serum cortisol levels, does not allow us to assess for any sex differences in the efficacy of BLAST and limits the degree to which we can extend the findings in this study sample to the population 28. In addition, only two time points were chosen at which to calculate the two metrics of the stress response. This limited sampling perhaps fails to fully characterize the time dependent response of BLAST on the stress response induced by the TSST. Increasing the frequency of datapoints and extending the time period may reveal more precisely how rapidly the stress response (as estimated by salivary cortisol levels) is attenuated and for how long this effect lasts.

The application of BLAST using TouchPoints™ was effective in reducing subjective levels of emotional stress, as well as physiological stress as evaluated by salivary cortisol levels in subjects undergoing the TSST as compared to controls. This suggests that bilateral alternating somatosensory stimulation may provide a non-invasive, non-pharmacologic means of managing stress in real time situations when other treatments may not be available or practical. Further research is needed to more completely evaluate these effects and to validate them against current conventional methods for reducing stress.