The Delta waves range from 1-3 Hz; these frequencies can assist in enhancing deep sleep. They also play a big role in boosting the immune system to facilitate natural body healing. The Theta waves have a frequency that ranges from 4-7 Hz. In turn, this brain state can enhance deep relaxation and is known to assist individuals who have poor memory. They are the best frequencies to use if you want to focus or meditate.
To summarize all this, we can see that the type of product you choose plays an important role in answering that question – “Can brainwave entrainment damage my brain?” My personal advice as a long-term user of the technology is to Be selective about what brainwave entrainment audios you download from the internet, and make sure to follow the instructions! 
Rudy's primary work is on Alzheimer's. In this disease, beta amyloid proteins form plaques in the brain and kill nerve cells eventually leading to dementia. Research from Washington University School of Medicine in St. Louis shows that when people's brains are in a Delta brain wave state, beta amyloid production in the brain ceases and the toxic material is cleared away. One thought is to explore the possibility of using brain entrainment technology to help treat Alzheimer's, but at this point all it is being used for is to help people meditate, relax and dream instantly and effortlessly.
The brain produces electrical signals. These signals change depending on what we are doing and what mental state we are in. For instance when we sleep these signals are different from when we are awake. This brain activity can be measured with EEG. It will output in Hz (Hertz - cycles per second) these electrical signals. The most dominant brainwaves will tell us what sort of state a person is in. The slower vibration (lower Hz), the more relaxed that individual is. Using audio technology we get the brain to start following the beats or pulses in a sound if done exactly right.
Clinical testing of Brain Sync programs resulted in a record-breaking 87% success rate. They are offered to patients at America's most prestigious hospitals such as Sloan Kettering and Dana Farber Institutes. EEG studies conducted at Harvard Body Mind Medical School, and UCLA concluded that Kelly Howell's Brain Wave Audio Technology® prompts brain activity into extraordinary body-mind states. Vist our Research Findings page for a full list of articles from the Harvard Medical School, the U.S. National Institutes of Health and Psychology Today that concur: the benefits of guided meditation, binaural beats, brainwave entrainment and positive subliminal messaging are real and profound. To learn more see this article about brainwaves in Scientific American.
While originally brainwave entrainment was achieved by using pure tones of sound, it is now possible to take these tones and blend them with music, rhythms, and natural sounds, such as the sounds of flowing water, bird sounds, or waves lapping on a beach, creating extended tracts of varied and intriguing brainwave entrainment music for everyday use.
Hi Julie! You’re very welcome for the info. In answer to your question, I think some are probably good, and some not so good. There are many people putting brainwave entrainment out there these days and it is not so easy to figure out which ones are and aren’t of reliable quality without investing time and doing some research. I would say (in general) that paid products are probably better quality than free ones, but I couldn’t guarantee this is a golden rule. My best advice is to just do your research before spending too much time listening to the freebies.

According to both observation and research, after a series of brainwave entrainment practices, the brain learns how to state change. This enables you to achieve certain brainwave effects in the absence of entertainment. Additionally, research shows that children are usually in the Theta stage and this in itself could provide a detailed explanation for their ability to learn fast and remember what they have learned. We can take advantage of this effect and use Alpha and Theta waves to reduce learning time in adults.

While a practical understanding of brainwaves has been around for as long as people have been singing, chanting, and drumming, a scientific view of the electrical activity inside the human brain was not published until 1924 when German psychiatrist Hans Berger developed a machine for sensing and recording activity in the brain by attaching small electrical sensors to the scalp of his patients and recording the resulting electrical activity. Berger’s inventions and discoveries were built upon the earlier work of Richard Caton who published animal studies on brainwave oscillations in 1875.
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.
Personally I use them whenever I feel like it which is often and experience truly amazing and almost immediate life-changing, and surprisingly great results. You can, and I am, literally the most confident, happy, sociable, smooth, funny,smart or intuitive person ever using these recordings. They also have the power to make you tonnes more money by giving you truly amazing wealth psychology. I use them successfully in helping me to make a tonne of money trading stock and other activities.
From a brainwave entrainment effectiveness perspective, it’s my understanding that the response from isochronic tones stimulation starts to diminish over 30Hz and that 40Hz is about the limit for using them. So from what I’ve read on the topic a 100Hz beat wouldn’t work, probably because it’s too fast for the brain to process and synchronise with it.
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.

Holosync is often seen as the ‘gold standard’ of brainwave entrainment. The Holosync program features 13 different levels which are listened to for 4-6 months before your brain will have adjusted enough to the technology to be able to move on to the next level up. Starting at level 2 of the program, Holosync goes the extra mile by incorporating your own chosen positive affirmations – recorded in your own voice.
Until NeuralSync™, brainwave entrainment involved inferior linear, single or sequential protocols - such as binaural beats or isochronic tones - that were natively restricted in their ability to affect the natural complex dynamics of the brain. But now, NeuralSync™ significantly improves entrainment by incorporating EIGHT SEPARATE BUT SYNERGISTICALLY-INTERACTIVE DIMENSIONS into a dynamic and cohesive process powerful enough to compel the brain to produce whole-brain synchronization for intense effect. Incredibly superior to binaural beats or isochronic tones, NeuralSync offers an entrainment experience beyond anything you've used before.
Brainwave entrainment is clearly NOT an effective standalone treatment for mental illness, but it may be an effective adjunct treatment in certain individuals. It should also be mentioned that when using brainwave entrainment, you may want to have a specific purpose in mind. If your goal is to relax, yet you’re using a protocol that is stimulating, you may falsely conclude that it doesn’t work even though you’re using the wrong protocol.
Thanks for your compliment on my article. 🙂 There are some frequency lists which reference and quote some links to metabolism, but I don’t know how effective or reliable that information is. One of the good things but also a drawback of this technology is how accessible it is to use and create tracks. That makes it unattractive for big companies to invest in large-scale research because it’s hard to patent and protect any product they produce based on the research. As soon as they released the frequency data, people like me would produce free videos and cheap MP3s to utilise the research, so they wouldn’t be able to get a good return on their research investment. So to try and gain some insight into what is working for people, at the moment, we are relying upon assessing anecdotal feedback in many areas. Before buying any products/tracks for increasing metabolism, I would look for and try out free videos on YouTube first, to try and gauge how those particular tracks and frequencies work for you.

“A quite different phenomenon results when stereophonic earphones are used and the signals are applied separately to each ear. Under the right circumstances beats can be perceived, but they are of an entirely different character. They are called binaural beats. . . . Binaural beats require the combined action of both ears. They exist as a consequence of the interaction of perceptions within the brain.”
NeuralSync™ is the ONLY technology that utilizes FOUR SEPARATE yet synergistically-interactive frequencies precisely calculated to induce each mental state offered in our catalog. Our exclusive 4-W.T.S.P.™ technology creates waves in a balanced 4-dimensional pyramid that are collectively complementary and interactive. Unlike other related programs that use only a single binaural beat or isochronic tone frequency (or several in sequence), NeuralSync™ applies all four simultaneously to immerse your brain into targeted and harmonizing perspectives.
I definitely NEED (& can feel a difference mentally) Gamma the most. Beta and Alpha do better my processing. Theta waves are TERRIBLE! My normal symptoms increase when listening to those frequencies! Delta has been helpful for me around nighttime. It has helped my sleep on occasion. *Note: Do not listen to higher frequencies (Gamma, Beta) before bedtime! They will keep you very alert.
While binaural beats are the most common technique we use for producing brainwave entrainment music, we do use other brainwave entrainment techniques such as isochronic tones, monaural beats and amplitude modulation. If these techniques have been used then you will find them mentioned in the written description of the music productions that include them. If not mentioned, then you can assume that binaural beats are the only brainwave entrainment technology in use.
Audio-Visual Entrainment (AVE) is a technique that utilizes pulses of light and sound at specific frequencies to gently and safely guide the brain into various brain wave patterns. By altering your brain wave frequencies, you have the ability to boost your mood, improve sleep patterns, sharpen your mind and increase your level of relaxation, all with the simple push of a button!
1) Theta Music Meditation from Unexplainable Store. Yep, you guessed it, this is a meditation MP3... with music. Boom. This is a nice, simple, powerful 20 minute session and (like all my recommendations) guaranteed 100% to work every time. Find yourself drifting away with this awesome recording, and start to reap the benefits of your underused theta brain waves. Simple and understated, my favourite.
Entrainment is a term originally derived from complex systems theory, and denotes the way that two or more independent, autonomous oscillators with differing rhythms or frequencies, when situated in a context and at a proximity where they can interact for long enough, influence each other mutually, to a degree dependent on coupling force, such that they adjust until both oscillate with the same frequency. Examples include the mechanical entrainment or cyclic synchronization of two electric clothes dryers placed in close proximity, and the biological entrainment evident in the synchronized illumination of fireflies.[13]