WINSTON-SALEM, N.C. – April 19, 2017 – A closed-loop
acoustic stimulation brainwave technology significantly reduced symptoms in
people suffering from post-traumatic stress in a small pilot study conducted at
Wake Forest Baptist Medical Center. The study is published in the April 19
online edition of the journal BMC Psychiatry.
“The effects of chronic stress are killing people and the
medical profession has not yet found an answer for how best to treat them,”
said Charles H. Tegeler, M.D., professor of neurology at Wake Forest School of
Medicine, a part of Wake Forest Baptist. “We believe there is a need for
effective, non-invasive, non-drug therapies for symptoms of post-traumatic
stress, which is why we conducted this trial.”
Nineteen volunteers who reported high scores on the
Post-traumatic Stress Disorder Checklist, civilian version (PCL-C), a commonly
used symptom inventory, were included in this single-site study. Of those, 18
completed an average of 16 sessions over a total of 16.5 days, with eight days
of actual visits to the office, Tegeler said.
The intervention, high-resolution, relational,
resonance-based, electroencephalic mirroring (HIRREM), focused on the brain,
which is the organ of central command for managing responses to threat and
trauma. Participants received a series of HIRREM sessions in which brain
electrical activity was monitored with scalp sensors, and software algorithms
translated selected brain frequencies into audible tones in real time. Those
tones were reflected back to participants via ear buds in as little as four
milliseconds, providing the brain an opportunity for self-optimization of its
As a closed-loop neurotechnology, the process did not
require any conscious, cognitive activity by the participant, who merely
relaxed and listened to the tones.
“It’s as if the brain can look at itself in an acoustic
mirror, recalibrate its patterns towards improved balance and reduced
hyperarousal, and can relax,” Tegeler said. HIRREM was developed by Brain State
Technologies based in Scottsdale, Arizona, and has been licensed to Wake Forest
Baptist for collaborative research since 2011.
Participants completed the PCL-C, and 12 also had continuous
recording of blood pressure and heart rate, before and after the intervention
sessions. Changes in asymmetry of temporal lobe high frequency brain electrical
activity was analyzed from baseline assessment through the first four sessions,
and again for the last four sessions. Autonomic cardiovascular regulation was
evaluated using measures of heart rate variability and blood pressure
modulation before and after the intervention.
After the sessions, 89 percent (16 of 18) of the
participants reported clinically meaningful decreases in symptoms of
post-traumatic stress as indicated by a change of at least 10 points from their
baseline PCL-C score, Tegeler said. In the entire study group, the average
reduction in the PCL-C score was 24 points. There were no adverse events
There is ample scientific evidence that there is some brain
pattern asymmetry associated with chronic stress. This study is important
because it also showed that there was improved balance in brain pattern
activity and significant improvement in the autonomic nervous system function,
as measured by heart rate variability and blood pressure modulation. All are relevant to a state of chronic
stress, which now seems to affect so many people, Tegeler said.
Study limitations included the case series design and the
absence of a control group. Additionally, participants were selected based on
self-reported symptoms and on the PCL-C score rather than a formal clinical
The study was supported by a grant from The Susanne Marcus
Collins Foundation, Inc., to the Department of Neurology at Wake Forest
Co-authors include: Jared F. Cook, M.A., Catherine L.
Tegeler, B.S., Joshua R. Hirsch, B.S.E., Hossam A. Shaltout, Ph.D., Sean L.
Simpson, Ph.D., Brian C. Fidali, B.A., of Wake Forest Baptist; and Lee Gerdes
and Sung W. Lee, M.D., of Brain State Technologies.
More information on this research program can be found at