A PRIMER ON BINAURAL BEATS
Somadome uses binaural beats to achieve beneficial states associated with your session goals.
Binaural beats are believed to affect the brain for purposes of modified human performance in areas of mood, attention, and perception of sensory information (including pain). Although binaural beats have been tested for decades, it can be very difficult to identify evidence-based claims among anecdotal case reports, uncited studies, and marketing materials that come up in most searches. A small number of scientific studies have been performed, including some Class I evidence with randomized clinical trials, with evidence building towards specific indications for their use. This White Paper will describe the process of brain entrainment, review evidence on binaural beats from
scientific or psychological studies, discuss the limitations of existing findings and suggest questions for further research.
BINAURAL BEATS EXPLAINED
BRAINWAVE BASICS
Delta < 4Hz: Commonly seen in slow, non-REM sleep, has a role in declarative memory
Theta = 4 – 7.9Hz: Reported in meditative states, also seen in REM sleep, euphoric states
Alpha = 8 – 12.4Hz: Baseline relaxed state, also seen in REM sleep, attentive states
Beta = 12.5 – 24.9Hz: Baseline walking state, also seen under the influence of anti-anxiety drugs
Gamma > 25Hz: Bursts with site-specific utility
ENTRAINMENT : Synchronizing Brainwaves with Sensory Information
BINAURAL BEATS AND EFFECT ON BRAIN STATE
DISCUSSION
First, there are general limitations regarding claims of EEG association with mood states – reporting of 140 141 both of these measures has a degree of subjectivity, in that mood is reported by survey and thus suffers immediately from recall and observation bias. So associating even a known EEG finding with mood to establish a baseline to test the binaural beat technology against is problematic. Likewise, EEG findings are not necessarily known for reliability – for example there is often considerable inter-rater reliability for clinical diagnoses (Benbadis 2009). Thus, results that find effects on comparatively more difficult states of attention or relaxation, often used as outcomes in neuropsychological studies, must be taken with some caution. In the case of studies discussed here, some care was taken to refer to work using generalizable metrics such as standardized surveys used in the FDA approval for anxiety medication (STA-I), or using randomized placebo controlled design.
Next, there are limitations to generalizing binaural beats across the range – just because the 9Hz binaural beat generator used for 20 minutes yielded a reproducible entrainment to alpha in study subjects, does not mean that the 9Hz binaural beat generator you have downloaded will produce the same result in you. Test conditions vary, as do tone used, volume, degree of noise cancellation and sensory isolation. Most importantly, the training used to prime expectations in study subjects can have a strong impact on outcomes. Any of these factors may modify the experience, and the extent to which they affect efficacy of brain entrainment is not known. For these reasons and others, an isolated and comfortable environment with limited distractions is an important component to creating a predictable binaural beat exposure process and results.
Finally, and perhaps most importantly, binaural beats suffer from many of the same limitations as other treatments that are not yet FDA-approved, namely lack of indications for their use, and lack of a dose-response curve for efficacy. Since these do not exist, caution should be taken while interpreting any claims made regarding a specific symptom that will be treated through a binaural beats exposure. However, a sufficient amount of evidence appears to justify the claim that binaural beat exposures of approximately 20 minutes can be effective at assisting transition to states of reduced anxiety and increased attention, and may even have utility for reducing the perception of pain – it would be useful to see studies that reproduced the findings cited here. There are other, less well described but significant areas of exciting research ongoing for use of binaural beats to assist in reducing insomnia, for improving performance in cognitive behavioral therapy sessions when used as an adjuvant to traditional psychotherapy.
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