The reason this rule of thumb is so useful is because there is a huge market for simple answers. A genuine elegant solution (one that accomplishes more with less) is highly valuable in the marketplace. We are used to technology delivering new easy solutions to previously difficult tasks. While most improvements are incremental, there are occasional breakthroughs that transform our lives.
Brainwaves, or neural oscillations, share the fundamental constituents with acoustic and optical waves, including frequency, amplitude and periodicity. Consequently, Huygens' discovery precipitated inquiry into whether or not the synchronous electrical activity of cortical neural ensembles might not only alter in response to external acoustic or optical stimuli but also entrain or synchronize their frequency to that of a specific stimulus.
Alpha Waves (7-13hz) are associated with light meditation, peak performance, creativity and relaxed alertness. Your brain goes into this state naturally when you are daydreaming. Alpha waves also become more predominant when you close your eyes and relax your mind. This is the perfect state to be in for subliminal mind programming and enhancing your creativity.
Theta waves also have been observed in moments when a person recalls information from the past, and this may be what links them also to improvement in learning ability. We also experience theta waves when we go into automatic pilot mode, such as when doing a repetitive task like driving a familiar route where the mind become disconnected while you still drive safely toward your destination.
Tracks that move from alpha to theta can be a perfect vehicle for transitioning from a hectic day into a relaxing and rejuvenating sleep. Beginning with alpha waves takes you into a light but still alert meditative mind state where the difficulties of the day can be resolved and put to rest. Later, theta waves go deeper into the unconscious, preparing you for sleep and dreams.
Delta brainwaves have the slowest frequencies, ranging between 0.1 and 4 hertz, and these are the brainwave states associated with deep sleep, trance states, and unconsciousness. Few people can remain awake during delta brainwaves states, although this state is recorded in awake infants between ages of three months and one year and also in babies just before birth. Delta waves are also linked with increased production of HGH, DHEA, and the neuro-transmitter serotonin.
If brainwave entrainment leaves you with unwanted side-effects (see below) or discomfort, you’re probably encouraging a range of brainwaves that are already excessive in some area of your brain. The way around this is to get a brain map to see what your brain’s strengths and weaknesses are, and see what (if any) brainwaves could use some encouragement.