EPSILON (below 0.5 Hz) Consciousness researcher Dr. Jeffrey Thompson altered conventional EEG equipment to study the extraordinary states of consciousness of seasoned meditators and yogis. He later decided to call one of the uncommon states of consciousness he discovered “Epsilon”—a brainwave pattern even slower than delta. Dr. Thompson measured the range of this pattern to be from below 0.5 Hz (or cycles per second) to as low as one quarter cycle every ten seconds. He also discovered properties of this pattern that led him to believe it to be a carrier wave for the ultra-fast brainwave patterns he observed in other expert meditators, patterns as fast as 200 Hz or more, suggesting a curious circular relationship between the fastest and slowest possible ranges. [source: iAwakeTechnologies.com]
Binaural Frequencies
DELTA (0.5 to 2 Hz) Delta brainwaves are predominant during dreamless sleep, the phase of the dream cycle also known as “deep wave sleep.” Deep wave sleep is all about growth and preservation of health: the immune system gets strengthened and muscles and tissues are mended. So, too little time spent in this state can be damaging, as the body refills its energy reservoir during this phase. Trained meditators and healers often display stronger delta waves than the standard population during sessions, and often report states of no sensation (even awareness of our bodies can disappear) and deep spiritual connection. Delta brainwaves are also considered our connection to intuition and the “seat” of all unconscious processes. If they naturally abound while we are awake, they can make us really empathetic as well as interfere with our cognitive tasks and emotional processing.
THETA (3 to 7 Hz) Theta brainwaves are naturally occurring during the hypnagogic state (pre-sleep), REM sleep, and often predominate during deep meditation and healing states of visualization, hypnosis, trance, and psychonautic exploration. This brainwave bandwidth is typical when awareness of the information coming in through our physical senses decreases, as we turn our attention inwards and our body rhythms (heart and breathing rates) slow down. It’s the gate to our buried memories, unresolved issues, and emotional trauma, and reviewing this material can sometimes be unpleasant as we might access and feel our raw emotion (previously supressed). Even though REM sleep already serves that purpose, it is important to include deep relaxation exercises in our routines, so healing and restoration of mind can occur. Theta brainwaves are related to insight, visualization, and deep states of meditation, although they can also make you drowsy and be responsible for distractibility, moodiness, and lack of focus.
GAMMA (26 to 99 Hz) Gamma brainwaves are fascinating. First because they disappear during anesthesia, suggesting an intrinsic relationship to consciousness itself, but also because they abound in the brains of Tibetan monks, who are long-term loving kindness meditators. So gamma waves seem to be central to harmony— perhaps even the brainwave signature of compassion itself. Gamma arises while processing all that comes in through our senses, as if they are the glue that helps us have a coherent picture of all the sensory data we receive moment to moment. They’ve been found to be linked to heightened perception, extremely creative states of high performance, focus, and clarity, as well as to high intellectual comprehension and acute self-awareness and spiritual insight.
ALPHA (8 to 13 Hz) Serotonin is released in higher quantities during alpha brainwave states, so there’s a feel-good effect to them—our bodies and minds relax and our emotions are in balance. They are considered a reliable marker for cognitive efficiency and often decrease with aging, which is why they’re tackled in most brain-brightening neurofeedback protocols. Their amplitude naturally increases when we go idle, close our eyes, watch a film, or daydream, so they are associated with states of relaxed awareness and light meditation. Alpha waves are also prominent in peak performance states and are even said to be “the artist brainwaves,” so alpha states are usually associated with a mix of creativity and presence. We’re in alpha when our imagination sparks, when we can enjoy our attention being placed on the inner and outer worlds at once, find alternatives and solutions to problems old and new, even experience a sense of increased capacity, deep belonging, and flow. Plus we need a strong alpha in order to remember what happens during states of trance, deep meditation, and dream sleep, so they’re fundamental to our spiritual growth. However, having too many of them can also make you spacey, inattentive, even depressed.
BETA (14 to 25 Hz) Beta brainwaves are produced when we focus our attention on the external world, feel more positive, energetic, goal-oriented, or are immersed in tasks needing our intellect and linear cognitive abilities, such as reading and analyzing this text, categorizing, or planning. Beta states makes us feel more social and witty (they’re related to high speed thinking and processing), and are all about physical and mental readiness, logic, concentration, and focus. Spending time in beta can lead to a really enjoyable mix of anticipation and determination, but it’s also where our busyness and critical self arise. High beta frequencies are as related to excitement as they are to body tension, high arousal, nervousness, rumination, insomnia, addiction, fear, and post traumatic stress disorder.
Deeper insight on binaural brain entrainment and neuroplasticity
As you read this text, billions of brain cells are generating measurable electrical activity across your brain. Extensive scientific research has revealed how all our mind states (relaxation, focus, anxiety, sleep, meditation…) correspond to specific brainwave patterns. All the feelings, thoughts, and actions we engage in on a daily basis are somehow electrochemically rooted in neuron-to-neuron communication and so reflected in our ever-changing brainwave states.
Due to the tendency of our brains to synchronize with external stimuli, it is possible to use sound to influence the amplitude of our various brainwave frequencies. For example, as you listen to an alpha brainwave track, certain areas of your brain want to quite literally follow the rhythm and get synchronized to the speed of alpha waves. When that happens, you might feel the calm and open focus that is associated with alpha rhythms.
Thanks to neuroplasticity (the brain’s endless and amazing capacity to change, adapt, and reorganize itself), the more frequently you enter a state, the easier you are able to go back to it. Brainwave entrainment lets your brain calm down or speed up, depending on your needs. Let’s look at the various brainwave frequencies and states. Binaural beats were discovered in 1839 by a German experimenter, H. W. Dove, and first described by Oster in the early 70s. How exactly the brain produces the perception of these beats is unclear, but they are said to be produced as the olivary body of the brain tries to “locate” the direction of the sound in response to two different tones being presented separately to each ear – which, if you think about it, is not something that would happen in nature unless via technological aids. The resulting phantom frequency (which is not heard in the ordinary sense, as it’s created inside the cranium) equals the difference between the tones, and prolonged exposure to its beating has a marked yet still debated psychoacoustic effect: while they do not seem to significantly impact the thalamus (no measurable entrainment response), their relaxing, even hypnotic effects can tangibly affect mood and performance and are enjoyed by most listeners