Recently developed entrainment software has been designed to correct specific imbalances in hemispheric activity associated with undesirable mind-states. For example, people suffering with depression often have more activity in the right hemisphere, and specially designed brainwave music decreases this activity while increasing activity in the left hemisphere, reducing depression.

One of the most fascinating and beneficial things about Delta brainwaves is their ability to stimulate the release of anti-aging hormones in the body, such as HGH (human growth hormone). Increased melatonin levels are also common in this state, and regular visits to Delta have also been shown to decrease cortisol levels. (Cortisol is a hormone that is released during stressful situations, that has been linked with the aging process.) In a nutshell, Delta brainwaves are very healthy, and until now have only been accessible to us during deep sleep.
In fact, there is more to answering this question than meets the eye. As someone who’s also been skeptical enough to do the research, I am more than happy to explore the issue in great depth. The important thing to address here is what have you been told that Brainwave Entrainment would do?  Depending on whose site you’ve landed on you may have been promised different things.  The promised benefits of this type of product are a long list, and more things are still being added to it.  You may have been told that brainwave entrainment would help you meditate deeper, and rocket launch your spiritual evolution from doing so.  You may have been told that it would help your brain release positive neuro chemicals and anti-aging hormones that would improve your health and help you feel more positive emotions, overcoming anxiety, and you also may have been told that listening to brainwave entrainment on a regular basis would help your brain evolve, building a higher threshold to mental and emotional input, growing neural pathways, and synchronising the two hemispheres of the brain.
Neural oscillations are rhythmic or repetitive electrochemical activity in the brain and central nervous system. Such oscillations can be characterized by their frequency, amplitude and phase. Neural tissue can generate oscillatory activity driven by mechanisms within individual neurons, as well as by interactions between them. They may also adjust frequency to synchronize with the periodic vibration of external acoustic or visual stimuli.[3]