The group is loud and boisterous, cheering on their favorite team, jeering at the referees, complaining about bad calls, laughing at some of the terrible acting of the players as they writhe in agony on the ground in an attempt to get the referee to call a foul on another player, and then as soon as the call is made they spring to their feet and trot off, all memory of the agony of a moment before completely forgotten.

They came to the table with the idea that the entrainment track would “cause” them to be in meditation, which it doesn’t. Or they thought that having the specific brainwaves the entrainment program promotes would “cause” them to be in meditation. It doesn’t. If you really understand the principles above, you’ll understand why. If you don’t grasp why yet, read these principles again and consider what they really mean. The answer is there.

For our ancestors, stress was a survival skill during brief, life threatening situations. Once the danger passed, their stress levels lowered. However, in today’s world, we are constantly bombarded by stressors, such as work deadlines, traffic, and family obligations. We rarely get a break long enough to relax and relieve the stress. The over-activation of our stress hormones have been linked to high blood pressure, heart attacks, lower immunity, depression, anxiety, and more.
Brain wave entrainment is a real phenomenon and is useful as one method of investigating how the brain works. But there is no evidence, nor any theoretical basis, for any long lasting effect on brain function or that there is any benefit of any kind. Despite this, there is a huge industry of devices that claim to train your brain waves and have a beneficial effect. I wouldn’t waste a dime on any such device.
I appreciate your compliment on my article Henry. I’ve been using and reading up on isochronic tones and brainwave entrainment for many years, so it was just a case of trying to put a lot of what I’ve learnt into one article. I don’t have a great deal of knowledge or experience in using hypnosis and subliminals, so I’m afraid I wouldn’t be in a position to create something so extensive in reviewing them.

Gamma waves are the most recently discovered brainwave, a discovery made possible by digital EEG technology. Gamma is associated with the integration of information from different areas of the brain, and having a good memory is associated with having a certain baseline of 40 hertz gamma activity. Low gamma activity is associated with learning disabilities and poor memory.

There are various reasons we seek this sort of validation. Many of us first try meditation to find relief from all sorts of different problems. Some seek relief from physical or emotional ailments; for solutions to personality shortcomings, such as a short temper or a tendency towards jealousy, etc. Some problems may be quite serious, even life threatening. Our search for relief may have been going on for a very long time without having found exactly what we were searching for.

The brain is composed of millions of specialized cells called neurons. Neurons send signals to other neurons using electro-chemical messengers called neuro-transmitters that attach to receiving sites located on the neurons themselves. There is a space between the end of the neuron and the receptor called the synaptic gap. As neuro-transmitter chemicals move across this gap, a small electrical charge is created. 
“…humans have always been intrigued by the possibilities for influencing mental functioning that emerge from combining rhythmic sound and rhythmic light stimulation. Ancient rituals for entering trance states often involved both rhythmic sounds in the form of drum beats, clapping, or chanting and flickering lights produced by candles, torches, bonfires, or long lines of human bodies passing before the fire and chopping the light into mesmerizing rhythmic flashes. From Greek plays to Western opera, our most popular entertainment forms have made use of combinations of lights and sounds. Some composers, such as the visionary Scriabin, actually created music intended to be experienced in combination with rhythmic light displays.”
Stress is a significant individual and public health problem that is associated with numerous physical and mental health concerns. It is estimated that between 75% and 90% of primary care physician visits are caused by stress-related illnesses (2). Cardiovascular disease, obesity, diabetes, depression, anxiety, immune system suppression, headaches, back and neck pain, and sleep problems are some of the health problems associated with stress (4,8). These conditions are some of the most burdensome health problems in the United States based on health care costs, the number of people affected, and the impact on individual lives. Extreme levels of stress were reported by 22% of respondents from the 2011 Stress in America™ survey, and 39% reported that their level of stress had increased during the past year (3). More than 80% of the survey respondents at the WorldatWork Conference in 2012 reported that stress moderately or significantly contributed to their health care costs (6).
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.