For many years this principle of entrainment has been used as a part of neurofeedback to help patients change their brain wave patterns in the hope of ameliorating the symptoms of dysregulated brain processes that are hypothesized to contribute to various disorders such as ADHD, anxiety, and depression. There is some evidence that neurofeedback combined with photic stimulation (e.g. Hammond, 2000) can help depression and that auditory and visual stimulation can help cognitive abilities in children with learning disabilities (e.g. Olmstead, 2005). 

Other entrainment methods sometimes used include autopan modulation that moves sound in an 180º arc to create a desired tone. Harmonic box entrainment, invented by James Mann, uses a layering of binaural and monaural tones that alternate between ears, requiring headphones. Sound modulation and filtering, amplitude modulation, and pitch panning use diverse sounds to create rhythmic pulses matched to the desired brainwave frequency. 
I tried other companies the last few years or so….among the likes that mainly used binaural audio and the deepest I was really ever to achieve was alpha state….maybe theta once or twice over the last few years. It takes incredible dedication and practice to achieve the deep, renewing states of meditation that are most sought after…..I listened to the theta meditation mp3 last night and within what seemed like a few minutes my mind was flooded with imagery…memories long gone…my body was sleeping, heavy as lead, but my mind was crystal clear, aware of my surroundings. I could barely even open my eyes!
Gamma was dismissed as 'spare brain noise' until researchers discovered it was highly active when in states of universal love, altruism, and the ‘higher virtues’. Gamma is also above the frequency of neuronal firing, so how it is generated remains a mystery. It is speculated that gamma rhythms modulate perception and consciousness, and that a greater presence of gamma relates to expanded consciousness and spiritual emergence.

Brainwave entrainment music can be used almost anywhere and anytime, making this mood and self-improvement method versatile and flexible enough to do at work, while traveling, or at other times during the day. When used in the workplace during short rest periods, brainwave entrainment techniques can enhance concentration, communication, and work productivity.
The easiest way to meditate Reach the deepest levels of meditation Obtain clarity and insight Experience mind-still blissful peace Now you can quickly reach depths of meditation that would otherwise take years of practice to attain. Brain Sync s precision-engineered frequencies massage your brain into mind-still blissful states of peace. With this program 87% of research subjects who never meditated before were able to enter the theta state their very first session. Guided Meditation Kelly Howell guides you create your own inner healing sanctuary, a place where you can go to revitalize the very core of your being. You ll learn how to generate states of being that nurture your sense of self, your creativity, and the dynamic expression of your power in the world. Deep Meditation Completely free of spoken words, this program delivers a unique combination of brainwave frequencies that produce an extraordinary mind-awake/body-asleep state. Negative thoughts are dramatically swept away by brilliant flashes of insight and understanding as you experience untold depths of inner peace. Clinical studies show that theta meditation increases creativity, enhances cognition, deepens perception, aids in overcoming substance abuse, and awakens intuition. In just 30 minutes you ll reap the same powerful benefits meditation masters have documented for millennium. The results are profound. This 2-CD extra value package includes both Guided Meditation and Deep Meditation at a special price.
Research: the authors stated that qualitative electroencephalogram signatures needed to be developed for different disorders and tested using standard validated methods of psychological assessment. Larger RCTs were needed with clear inclusion criteria for participants. The RCTs should measure qualitative EEG, hormone levels and the time of day of the intervention. Interventions protocols should be clearly defined and the relationship between session frequency/ duration and outcomes should be explored. More studies of auditory stimulation were needed, as well as studies comparing different types of stimulation, monaural, binaural and isochronic beats and use of white noise versus music.
Business executive and radio producer Robert Monroe started experimenting with brainwave entrainment and has a series of powerful out of body experiences using it. In 1971 he published his cult classic “Journeys Out of the Body” sharing his experiences. He later created one of the first audio entrainment companies called Hemi Sync, alongside the Monroe Institute of Applied Sciences.
In the meta-analysis performed by Fox et al., several sources of bias were indicated which bring into question the validity of meditation studies which use neuroimaging. Fox et al. suggests a publication bias may be leading to the over-reporting of significant results.[18] Despite this, however, Fox et al. found "consistent differences in prefrontal cortex and body awareness regions" in "areas key to meta-awareness..., exteroceptive and interoceptive body awareness..., memory consolidation and reconsolidation..., self and emotion regulation..., and intra- and interhemispheric communication..." and that changes were significant with "moderate" global median effect size and "consistent and medium-sized brain structure differences."[18]
Our relaxing music is perfect for Deepak Chopra Meditations, Buddhist meditation, Zen meditation, Mindfulness meditation, Kundalini meditation, Qi Gong Meditation, Zazen Meditation and more. Our music is influenced by Japanese meditation music, Indian meditation music, Tibetan music and Shamanic music. Our instrumental music has been designed to encourage and enhance relaxation, meditation, brain function and concentration, spa and massage therapy, and healing music therapy. In addition, we use binaural beats (Delta, Alpha and Theta Waves) to naturally reach a state of relaxation perfect for concentration, meditation or deep sleep. Our music playlists are perfect for your daily meditation and relaxation. Our music videos use soundscapes such as nature sounds, animals, oceans, rain sounds, thunder sounds and many more).
According to the Wikipedia entry “(i)n acoustics a beat is an interference pattern between two sounds of slightly different frequencies, perceived as a periodic variation in volume whose rate is the difference of the two frequencies.” Further, a binaural beat is “… an auditory illusion perceived when two different pure-tone sine waves, both with frequencies lower than 1500 Hz, with less than a 40 Hz difference between them, are presented to a listener dichotically (one through each ear)”. If the two frequencies are, say, 5 Hz apart as in 500 and 505 Hz, then a third tone at 5 Hz will be heard in addition to the two pure tones. What this technique allows for is the creation of an apparent auditory signal that can be perceived and that is at a predictable frequency. In this way, relatively low frequencies can be generated that can be easily perceived and that can correspond to the common brainwave frequency bands. These are often categorized as delta (0.5 – 4 Hz), theta (4 – 7 Hz), alpha (8 – 12 Hz), and beta (13 – 16 Hz). You may find somewhat different ranges and bands other than these listed depending on the source you consult. It is also possible to produce flashes of light that can be administered within these frequency bands but there is some risk of inducing seizures in susceptible individuals. While the most common frequency range for inducing seizures is 15 – 25 Hz, unfortunately, the possible range is 1 – 65 Hz, which covers essentially the whole range of standard EEG frequency bands. This makes use of sound stimulation safer than visual or combined audio/visual stimulation. 

But what would be the point of generating a beat that was at the same rate as a certain brainwave frequency? First, consider that these frequency bands relate to different states of awareness. Delta is seen in deep sleep, theta in lighter stages of sleep, alpha when we are relaxed with eyes closed, and beta when we are awake and alert. Second, the main idea behind using binaural beats to help a person relax and sleep is that of entrainment. Entrainment means that a biological process is matched to some external stimulus. For example, our circadian clock is entrained to the day/night light cycle and helps the body organize physiological processes in an appropriate way over the course of the day. A repetitive sound at the frequency of a certain brainwave band could theoretically cause the brain waves to be entrained to that frequency and thus help induce the state associated with that brainwave band. This could have therapeutic utility.
Really great stuff here, man. Well done! Without taking anything away from the article it would have been great to have under one “roof” similar information about hypnotherapy and subliminals. I invested quite a lot in buying binaural cd’s but after reading your material I think that for short term effects isochronic tones rather than binaurals are the technology to go for now. For longer lasting and possibly permanent effects I’m not sure whether I should go for hypnosis or subliminals (or both). An article as well written and comprehensive as yours but focusing on hypnosis vs subliminals would have completed the circle for me. The stuff I’ve read so far on binaurals vs isochronics hasn’t really done it for me. Any chance you could give it a shot?
Like many complementary therapies, the issue most people have about meditation is in its execution. Thanks to the rapid rise of technology in our lives, we seem to be busier than ever. Our minds are occupied during most of the time we are awake, and we only really shut off when we finally go to sleep at night, which means that finding the opportunity to meditate daily can be difficult.

Slip on your headphones, close your eyes and turn out the lights. Within minutes you’ll feel like your brain is being massaged. Soothing Delta frequencies, associated with deep restorative sleep, and subliminal messaging for deep sleep are masterfully woven into gentle music. As your brain cells resonate and your brainwaves entrain with Delta waves, you start to slowly swirl and drift. Delta binaural beats help wash away pestering concerns, allowing you to fall into deep sleep states that bring the refreshing slumber your body and mind need for health, happiness and optimum performance.

Delta (3hz – 0.2hz) – Deep, dreamless sleep. Intuition. Empathy. Brainwave expert Judith Pennington calls it the doorway to Universal Consciousness and “A radar that scans the environment and psychically picks up information and energy.” According to British physicist C. Maxwell Cade “There have been reports that delta waves appear at the onset of paranormal phenomena.” (More information can be found in Cade’s book The Awakened Mind)

Joe:             The Journey  soundscape took a lot of work. I wanted to bring in the very best of what I knew about brainwave entrainment and to make the best brainwave entrainment product—with the best entrainment technology—that I possibly could. So, there are all sorts of things going on in Journey  to provide a sound bed to support the experience of expansiveness and also communicate elements of the heart-based work I talked about earlier. (See part I of this interview, A Guide to Transpersonal Meditation.)
Rather than discontinuing my meditation practice altogether, I instead began researching methods of increasing the effectiveness of meditative practice. This seemed an inevitable decision for me in light of the undeniable improvements I had witnessed in response to previous experience with meditation. This resulted in my eventual re-discovery of brainwave meditation programs brainwave synchronization. I had used a few different such products previously, but none that seemed effectively designed to meet my specific needs. After deciding to try a particular brainwave meditation program, I found it to greatly assist me in producing all of the previously experienced benefits of meditation, but in a shorter period of time and in a much more focused manner.
Other research by Paul Ekman, of the University of California San Francisco Medical Center, suggests that meditation and mindfulness can tame the amygdala, an area of the brain which is the hub of fear memory. Ekman discovered that experienced Buddhists were less likely to be shocked, flustered, surprised or as angry as other people. Flanagan believes that if the findings of the studies can be confirmed they could be of major importance.
A more extensive study of over 100 participants who were undergoing general anesthesia for a day procedure, reported a decrease in pre-operative anxiety. The participants in this study listened to 30 minutes of binaural beats before surgery, but the researchers noted that people experiencing high levels of pre-operative anxiety could listen to binaural beats for up to 1 hour before anesthesia to reduce levels of anxiety.