A study that tested photic stimulation for reduction of poor behavior in ADHD children found that 15 sessions of photic stimulation between 12 Hz and 14 Hz resulted in behavioral change. This behavioral change was measured using the Achenbach Child Behavior Checklist – which accounted for not only the parent’s perspective, but self-reports from the children. Statistically it was stated that behavior improved up to 70% in the stimulation group compared to controls.
One RCT (n=108) showed significant reduction in anxiety from a single session of alpha/delta therapy for day surgery patients. A crossover RCT of a single session of theta stimulation in four healthy adults reported significant improvement from the intervention in one of five measures. Five pre/post studies reported significant benefit from the intervention for 16 of 27 outcomes.
  There’s an added bonus feature you get with the Brain Evolution System™: scientific studies indicate that brainwave entrainment can not only enhance normal thinking to higher levels, but can also act as a “mood enhancer” to alleviate depression, chronic fatigue, and related conditions – as well as the physical symptoms brought on my too much stress.

Different people have different requirements when it comes to frequency changes in the music and it's quite impossible for us to anticipate them all. We would need to produce so many different variants of all our music productions that it would be impractical to manage and confusing for our customers. For example, if we were to start raising the frequency from theta up to alpha between the 50-60 minute mark of a piece of music, this would be useless to someone who used the music for a guided meditation that was only 45 minutes long. In the early stages of the development of our brainwave entrainment music we had so many different requests from different people that we could only opt for the simplest solution, which is to use a consistent frequency throughout. It might not be the absolute "perfect ideal", but this is still a very effective technique and the feedback we've received on our brainwave entrainment music has always been exceptionally positive.
But here is where I’d like to chime in my own two cents.  As a user of brainwave entrainment products for over 8 years now, you would obviously have to guess that I think this technology is fabulous.  Even my earlier experiences with brainwave entrainment technology using less refined binaural beats were nothing short of miraculous for me.  It’s a very fascinating experience to go from not being able to meditate at all to being able to sit with your eyes closed and headphones on and effortlessly slip down into deep brainwave states that were previously only reserved for years-long experienced meditators.
The activity of neurons generate electric currents; and the synchronous action of neural ensembles in the cerebral cortex, comprising large numbers of neurons, produce macroscopic oscillations. These phenomena can be monitored and graphically documented by an electroencephalogram (EEG). The electroencephalographic representations of those oscillations are typically denoted by the term 'brainwaves' in common parlance.[4][5]
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