Recent research at the University of Lisbon finally uncovered the reason for the 350 year-old mystery, finding that the resonance of sound is the mechanism for entrainment of swinging pendulums and ticking clocks, and it seems likely that the energy transferred by sound is also responsible for other observations of entrainment, including brainwave entrainment.
 It is a good idea to follow any instructions outlined by the makers of any type of brainwave entrainment product or program, and to ease yourself carefully into using it. If experiencing any negative side effects, take a break and come back to it later. Brainwave entrainment audios are not recommended for children under the age of 18, and should not be used while driving or operating heavy machinery.
my daughter had an EEG and the neurologist said the brain wave activity in the back of her brain was very slow. I want to find out what causes this. She had a brain injury (3 skull fractures that were in the right side of her head and across the front right side. The fractures were closed wound. She had a small amount of swelling which diminished on it’s own. The neurologist asked if the fractures were in the back of her head and I told her no. She had no explanation for me.
In 1956, the famous neuroscientist W. Gray Walter published the results of studying thousands of test subjects using photic stimulation, showing their change in mental and emotional states. He also learned that photic stimulation not only altered brainwaves, but that these changes were occurring in areas of the brain outside of vision. In Walter’s words:

This music encourages a state of alpha relaxation. The alpha state is a pleasant state of relaxed alertness. It’s a state that many people experience when they are waking up in the morning or when they are just beginning to drift off to sleep at night. While in a state of alpha relaxation, the mind is quite clear and receptive to information, learning is accelerated and one’s sense of creativity is enhanced. The mind is also very open to positive suggestions during this state.
So discovering the field of Brainwave Entrainment is very exciting and promising. However intriguing, there are a few things that make me a bit sceptical towards it. F.i. I’m not too keen on having to rely on any external stimuli, as (regular) meditation is one of the very few things where you are absolutely independent from anything external to make a change within, which to me makes it so special.
Theta brainwaves in the frequency range of 6 to 9 hertz are known as thalpha waves because of their proximity to alpha waves. They are seen during states of high suggestibility, during hypnosis, and during paranormal experience and are also connected to an increase in human growth hormone (HGH) levels and higher blood flow to the brain. Theta brainwaves sit between the realms of the subconscious and conscious mind, making them an especially useful brainwave state for developing creative thinking, working through emotional problems, and integrating subconscious and conscious experience. 
"I have been using Quantum Mind Power for two weeks and today I feel that although the changes are subtle, I have been able to overcome many roadblocks in my personal life. I have ADHD and have been taking Adderall for 7 years, recently I decided that I need to stop and have cut my dosage in half with the intention of completely stopping within a month.  I have also just started teaching Pilates as a second job.....
I received my order on Mon. and have done 3 or 4 sessions of Equisync I. I just wanted to say I can already notice a difference in myself. I am much calmer and more clear thinking already in just 2 days. I don’t think it’s my mind playing tricks on me. Is this a common occurrence? Your product is great I can’t wait to try Equisync II and Equisync III.
Your brain operates at certain levels of activity – the normal waking, active Beta, the meditative Alpha, the asleep-and-dreaming or deep meditative Theta, and the deep sleep/unconscious Delta. Beta is characterized by one thing we all want to get away from – stress.But that brainwave state has its place. It’s the action mode, and that’s the way it should be! If we’re not alert when we’re awake, bad things can happen, right?

The implications and potential benefits of brainwave entrainment technology are staggering, and a seemingly infinite amount of doors have been opened to be explored.  This technology is highly useful in the self-help/personal development field in a variety of ways.  It can also be used to enhance NLP and hypnosis recordings to make the mind more receptive to suggestion.  Brainwave entrainment can be applied to help people fall asleep, to improve focus and concentration, or to relax.  Recent and modern experiments are also being held to see if brainwave entrainment may help  to treat and/or cure mental “disorders” such as depression or ADD.  One of the most common and popular uses of brainwave entrainment is to effortlessly induce deep meditative states.
In March I started using the CDs that I affectionately call “Meditation for Dummies” and am very pleased with the results so far. My blood pressure has dropped, I am sleeping better and notice that I feel much more calm and less stressed. Instead of feeling that I need to “find the time” in my schedule to meditate, I look forward to that totally relaxing half hour–that peaceful feeling of floating.
Blisscoded sound is an invention, or rather a discovery of how to use the golden ratio principle to code sound, giving it properties that has a very strong calming effect on the mind. People use it for meditation, relaxation, sleep and just feeling great. On youtube, the first video I uploaded showcasing the sound has over 9 million views. That is for a reason.
When making an educated decision on what product is best for you, it is important to have a general understanding of how the technology works, and what the benefits are of visiting the specific brainwave states.  Please click the link to visit a more detailed article –  How Does Brainwave Entrainment  Work, and the benefits of Alpha, Theta, Delta, and Gamma brainwaves.
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.
Both brainwave entrainment and neurofeedback deal with brainwaves, but the similarity stops there. Entrainment pushes your whole brain into a pre-determined state, while neurofeedback teaches you how to move specific parts of your brain on your own. It is the differeence between forcing the brain into a given position, and skills building so you can move it there yourself. 
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