ta, alpha, beta and gamma.
1. Delta - Delta is the lowest of the frequencies, ranging from .5 to 4.0 cps (or Hz) and is normally associated with deep sleep. This frequency appears to be generated throughout the brain. Although it is the slowest of the brain waves, it is the level through which we access our unconscious mind.
The unconscious mind is not under our control. It's the marvelous mechanism that runs our autonomic nervous system. It makes sure all those aspects of our body that are important – like our muscles contracting and our heart beating – actually happen. It's also is a powerful data processor - constantly alert, observing, collecting, and processing data below the surface of our consciousness. As a result, psychologists often help patients enter the delta level in order to access the information in the unconscious mind.
2. Theta - With a frequency of 3.5 to 7.5 cps (Hz), theta is also a slow brain wave, but the dominance of theta waves in the brain opens a powerful portal to creativity. Predominantly a right brain experience, theta is the source of inspiration – the expansive, intuitive levels that ignite artists, writers, composers, and physicists with profound ideas and experiences. Also present in the dreaming sleep state, theta is visionary, providing spiritual experiences and deep meditation.
3. Alpha - The frequency of Alpha is between 8 and 12 cps (Hz), and is the “laid-back,” stress-free brain wave level. It's associated with clear, creative thinking, problem-solving, and the “flow” state where we feel balanced. Alpha is a brain frequency that stimulates serotonin, a neurotransmitter that stimulates a positive mood. It's also a bridge frequency between beta – the waking, active level - and the levels of theta and delta where other parts of the consciousness structure are accessed. The unconscious levels are normally not available to the beta state.
4. Beta - Beta is the fastest of the brain wave categories at 13 to 30 cps (Hz.). It is considered the normal, waking, active state. The presence of beta waves in the brain promotes high states of functioning – quick thinking, left-brain-analytical thought, focused alertness, social dominance, goal setting – all of the aspects we think of as success-oriented in our Western society.
5. Gamma - Gamma is a remarkable state that occurs above 30 cps (Hz) and is considered the optimal operating level of the brain. Gamma is associated with highly integrated thinking, increased mental and learning abilities, enhanced awareness of reality, and greater memory capabilities. Gamma waves occur strongly throughout the brain and are the binding mechanism that connects information, bringing greater perception and increased sensory acuity. Gamma also facilitates a flow of information from the unconscious levels to the conscious mind. It increases spiritual activity and compassion, and is found in very high quantities in advanced meditators.