There are several levels of relaxation from fully alert and awake, all the way down to deep sleep. Each of these levels is represented by the brainwave frequency associated with it and has its own set of characteristics.
Gamma (above 40Hz) – Insight
Although some meditation gurus claim to reach brainwave levels in excess of 100Hz (Hyper-Gamma), Gamma waves are the fastest frequency known scientifically. Gamma waves are associated with higher processing tasks as well as cognitive functioning, insight and are important for learning, memory and information processing.
Beta (14-40Hz) – Waking Consciousness
Beta brainwaves are associated with normal waking consciousness and a heightened state of alertness, logic and critical reasoning. They are important for daily functioning, however, they can also translate into stress, anxiety and restlessness.
Alpha (7.5-14Hz) – Deep Relaxation
Alpha brainwaves are the bridge between conscious thinking and our unconscious mind. They are associated with deep relaxation and usually when the eyes are closed. This is usually the state you are in when daydreaming or during a light meditation. One can experience heightened imagination, visualisation, memory, learning and concentration.
Theta (4-7.5Hz) – Sleeping & Meditation
Theta brainwaves are associated with deep meditation and light sleep, including REM (Random Eye Movement) sleep or the dream state. This is where your unconscious mind rules and you can experience vivid visualisations, great inspiration, profound creativity and exceptional insight. Experiencing deep and raw emotions can also be achieved.
This is also the level of deep hypnosis as the unconscious mind is most susceptible to suggestions at this level.
Delta (0.5-4Hz) – Deep Sleep
Delta brainwaves are the slowest and are associated with deep, dreamless sleep and in extremely deep meditation where awareness is fully dissociated. Quality deep sleep is important for the body to heal. Not having enough deep sleep is detrimental to your health in a number of ways.