Controlled or pre/post studies of the effects of BWE using auditory or visual stimulation were eligible for inclusion, provided pulses of light or tone were delivered at frequencies hypothesised to have a beneficial effect or in line with a protocol addressing clinical outcomes. Studies were required to report clinical or psychological outcomes (measured using standard methods or as deemed appropriate by peer review) and to report statistical analysis. Studies of outcomes such as electroencephalogram (EEG) response or neurotransmitter levels were not eligible. Case studies were excluded.

Binaural Beats or “binaural tones” are created by playing slightly different frequencies separately into each ear. The difference between the two frequencies stimulates a response in the brain which correlates with this frequency difference. For example, if we present a 100 Hz tone to the left ear and a 105 Hz tone to the right ear, a frequency of 5 Hz is stimulated. This is what is known as the “frequency following response”.

Much of what is currently written about brainwave entrainment, especially on the internet, is simply … incorrect.  It seems par for the course that when something of huge value is discovered as a potential ‘internet product’ that it is going to be marketed within an inch of it’s life. And often with less than stellar regard for actual science, research, or factual knowledge. 
I'll give you a clue... How do you feel about money? Do you think you'll be rich, or do you worry about bills? Or... what do you think of yourself? Are you worthy of an awesome relationship, or will you just settle for the first person who comes along? Do you have your dream job or do you just do what you can to get by? Do you live life on your terms, or struggle desperately not to be noticed?

Brainwave Mind Voyages 24 CD Set: Brainwave Meditation Programs, Hemispheric Synchronization, and Brainwave Entrainment Technology (24 BMV CDs: Lucid Dreaming, Astral Trance, Alpha Brainwaves, Theta Brainwaves, Delta Brainwaves, Tones, Astral Vibrations, Remote Viewing, Beta Brainwaves, Lucid Dream Cycle, Lucid Dreams Hypnosis, Guided Dream Incubation, The Whales CD, Rainstorm, The Waters CD, Nature Sounds, Heartbeat Meditation CD, The Om Meditation, Ganzfeld Effect/ White Noise, Breathing Silent Mindfulness, Breathwork Yoga Yogic Breathing Techniques, Tibetan Singing Bowls, Schumann Resonance, Sacred Healing Frequencies Solfeggio Healing Tones)
It may be that you had the volume too loud, but I would expect you to hear the effects of that straight after you’ve stopped listening, not on a day you haven’t used them. It might be something similar to muscle memory, where you suddenly remembered the sound and sensations it gives you as if you were hearing it again. I don’t know how long you’ve been using this type of thing for, but maybe it’s something that will settle down and disappear once you become more accustomed to the sound.
There are differences between high (over 18 hertz), mid (15 to 18 hertz), and low range beta states (12 to 15 hertz). Low beta states are more relaxed while still being focused, making this a good range for many daily work related tasks like balancing a checkbook, making a shopping list, or driving to a new place. However, people with attention deficit disorder lack the mental focus for doing these types of activities, and studies have found people with ADD are often low in this range of beta brainwaves.

Transparent Corp's Research Area is arguably the most comprehensive resource for collated brainwave entrainment research.   Update: the main research area on Transparent Corp's website is currently being updated, so it is offline.  However, you can still access their peer-reviewed research paper as a PDF here: “A Comprehensive Review of the Psychological Effects of Brainwave Entrainment“.

By the end of just a few short days (3 or 4 of use), my constant “on edge” feeling completely dissipated. I had changed my lifestyle drastically to a very low-stress environment. All feelings of anxiety disappeared rapidly, but I was still experiencing something “physical.” I had trouble explaining it to anyone. I lashed out immediately at the slightest frustration. I tried to explain to those around me that it was something physically happening in my brain, but they were skeptical. Within less than a week of using the EOC cd’s, I noticed my tolerance level for dealing with people and situations had increased tremendously.

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.

The Brain Wave app uses advanced sequences of binaural tones that are combined with configurable ambient nature sounds and atmospheric music (or a person’s iTunes Music) to stimulate specific brainwave patterns.  It includes powerful binaural sequences for sleep, focus, energy, positive mood, confidence, anxiety, stress relief, relaxation, yoga, memory, motivation, headache, concentration and meditation and more.
This is probably the most popular choice of frequency. The theta state is a state of tremendous stress relief. The benefits associated with theta level relaxation include improved concentration, reduced hyperactivity and improved memory. While in a state of theta relaxation, one’s blood pressure, breathing and heart rate all slow to a much more restful and healthy level that promotes natural healing. During theta relaxation one may also experience vivid flashes of mental imagery as the mind opens to memories or subconscious information that is not available to the conscious mind during the normal waking state. The theta state is a very deep state of relaxation that is excellent for deep hypnosis and mental programming.
While it may not be a perfect therapeutic option for treating certain psychological conditions, brainwave entrainment is yet another tool that warrants further testing and exploration. There is clear evidence that certain protocols may benefit human performance. Unfortunately nearly all of the research has been conducted by those who clearly are affiliated with those who manufacture brainwave entrainment products.

When blended with musical sounds, brainwave entrainment frequencies induce specific states of mind, which are the result of those brainwaves, delivering them in pleasing and relaxing audio tracts for use with and without stereo headphones. For example, alpha and theta waves, because they exist at the borders between conscious and unconscious thought, are especially rich and useful for tapping into and stimulating subconscious processes.
Jump up ^ Bittman, B. B., Snyder, C., Bruhn, K. T., Liebfreid, F., Stevens, C. K., Westengard, J., and Umbach, P. O., Recreational music-making: An integrative group intervention for reducing burnout and improving mood states in first year associate degree nursing students: Insights and economic impact" International Journal of Nursing Education Scholarship, Vol. 1, Article 12, 2004.