Hemi-Sync® stands for Hemispheric Synchronization of the brain. All Hemi-Sync® CDs include special tones to induce the the Frequency Following Response that puts your brain into a coherent state while targeting different levels of consciousness such as high focus, relaxation, or sleep.
Each CD has a unique set of frequencies designed to bring you into specific consciousness levels from Delta for sleep up to Beta for high levels of focus and concentration. While listening to a Hemi-Sync® CD you enter into a whole brain state where the left and right hemispheres work together in a state of coherence.
The diagram above illustrates the way that Hemi-Sync® works. Depending on the difference between the two frequencies that you listen to through stereo headphones, your brain will naturally produce a brainwave equal to the difference of the frequencies. The brain waves experienced while listening to Hemi-Sync® are the same that your brain goes through on its own throughout the day. The difference is that by listening to Hemi-Sync® CDs your brain will stay in those frequencies–a great solution if you have trouble sleeping or have a hard time focusing when you need to.