There are five main categories of brainwave frequencies: Gamma (40Hz+), Beta (13 – 40Hz), Alpha (7 – 13Hz), Theta (4 – 7Hz), and Delta (<4Hz). Each category is associated with a different state of mind; so, for example, when you’re in a peak state of performance, your brain produces Alpha Waves, and when you’re in a deep sleep, your brain produces Delta Waves.

What are some common experiences or thought patterns that can cause the body to feel stress, including some that you might never have associated with stress before? Things like financial pressure, a lack of sleep, emotional problems in your relationships, overtraining or doing too much exercise, and even dieting can all send signals to the body that it’s under stress.

These brainwaves are actually a bit of a mystery. They’re the highest frequency you can achieve, but scientists are a little dumbfounded by them. Unlike the next set of brainwaves (Alpha and Beta), Gamma brainwaves don’t’ really translate to feeling active and alert. Rather, what’s been discovered is that in Gamma, neurons are firing so harmoniously, that people often feel like they are having a spiritual experience. This brainwave state has been associated with expanding consciousness and understanding the value of universal love and harmony.

Deeper Meditation • Near The Stage Of Sleep • Vivid, Dreamlike Imagery • Creative Visualization • Feel More Open & Connected • Advanced Problem Solving • Super Creativity • Insight • Intuition • Inspiration • Deeper Subconscious To Super-Conscious Mind • Trance-like • GABA • Immune System • Serotonin • Endorphins • Acetylcholine • Lower Cortisol • Deeply Relaxed • Sleep Better • Emotional Intelligence
This version of Theta Waves music is nice to listen to and the theta wave with binaural feeding of different wave lengths might be correct as the author indicates it, but for me it was disturbing that in the general sound track of a constant gliding sound I expect from Theta Healing CDs some ringing sounds like bells constantly interfered just in moments when the brain and mind would go into the meditation state and synchronize both sides of the brain. As I am a musician myself and use a lot of classical music but never normally use music for meditation, I felt a bit disillusioned from this CD. For the purpose of Theta Healing and deep Theta Meditation, I would not use this music, but prefer the Theta Healing CDs. I was really astonished that so many people say they can meditate deeply with this music. Perhaps my brain is somehow different. I asked myself if the author ever has experienced what a deep meditation with no thoughts and complete stillness is. Music is also able to distract us from true meditation and this kind of music does.

These tones are similar in that they pulse like binaural beats. The difference is that they don’t need to be listened to using headphones as the pulse, or beat, is not generated by two different frequencies. The sound is an on/off pulse. Although you don’t need headphones to seperate the frequencies listened to, they are recommended. I’ve had just as much response to isochronic tones as I’ve had to binaural beats. I’d try both though, especially if you don’t respond to one or the other.

Please note: When you take one earphone out, move it as far away from your ear as possible. With some headphones you may still be able to hear the pulsating sound if the removed headphone is still fairly close to your ear; this is because your brain can still detect the frequency vibration coming from the headphone. In addition, push the earphone that’s still on your ear tightly to your ear, while moving the other earphone as far away as possible.
Regarding split hemisphere isochronic tones. Think of this as two separate isochronic tones tracks playing independently of each other, one playing in one ear and the other one in the opposite ear. Better still, imagine someone playing and recording a drum beat at a rate of 5 taps per second (5Hz – 5 cycles per second). Then a separate recording of a drum beat is made at a rate of 10 taps per second (10 Hz). You then make an audio track where the left ear/channel hears the 5 drum beats recording and the right ear/channel hears the 10 beat recording. With headphones on, each ear can only hear each respective drum beat and not the other. So you are hearing two different beat recordings at the same time, but it’s different in each ear. A split hemisphere isochronic tones track works just the same. You hear two beats at the same time, not two tones as with binaural beats that create a single beat, but two different speeds of beats in each ear. This is what enables you to stimulate and influence each side of the brain with a different frequency of beat. Binaural beats can only stimulate and influence a whole brain effect using a single beat.

As to the second question raised in the above paragraph, audio with embedded binaural beats alters the electrochemical environment of the brain. This allows mind-consciousness to have different experiences. When the brain is entrained to lower frequencies and awareness is maintained, a unique state of consciousness emerges. This state is often referred to as hypnogogia "mind awake/body asleep."  
Subsequently, the term 'entrainment' has been used to describe a shared tendency of many physical and biological systems to synchronize their periodicity and rhythm through interaction. This tendency has been identified as specifically pertinent to the study of sound and music generally, and acoustic rhythms specifically. The most ubiquitous and familiar examples of neuromotor entrainment to acoustic stimuli is observable in spontaneous foot or finger tapping to the rhythmic beat of a song.