OK – so some of this is pretty common marketing hype. Consumers have become almost numb to such hyperbole. But still we see some of the common – almost ubiquitous – elements of pseudoscientific scams. The company claims that the device is “effort-free”, that the results are “rapid and long-lasting,” that it is the “most effective” method of its kind, and that it is useful for a broad range of applications (hey, why limit the market). I am used to such hype about dishwashing detergent, but find it intolerable when applied to a pseudoscientific device with medical applications.
Brainwaves are the collective electrical signal of millions of neurons working together in a living brain, producing our sense of alertness – or lack thereof - and producing our experience of reality. As brainwaves change, so does our perception of the world and our inner perception of ourselves. By learning to control our brainwaves, we can achieve specific, desirable mental states, such as feeling more relaxed, less anxious, more creative, more focused, or sleepier.
Gamma brainwaves possess the highest frequency we know of. In this state, our brainwaves are so harmonious that many people report feeling elevated states of consciousness, even spiritual experiences. This frequency is often experienced by monks, nuns, yogis, and experienced meditators. Gamma frequencies also enhance memory, awareness, and mental processing.
All of this is entirely understandable, even somewhat predictable. Unfortunately, it quickly becomes counter-productive. Such experiences, while having a certain feeling of solidity to them, are largely the product of our desires and expectations. Did your face get flushed? One look in the mirror confirms it did. Was this caused by the entrainment? No, it was not. It was the result of what was sought after and what was expected or even hoped for.
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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