Brainwaves are detected using sensors placed on the scalp. They are divided into bandwidths to describe their functions (below), but are best thought of as a continuous spectrum of consciousness;
It is a handy analogy to think of Brainwaves as musical notes - the low frequency waves like a deeply penetrating drum beat, while the higher frequency brainwaves are like a subtle high pitched flute. Our brainwaves change according to what we’re doing and feeling.
Brainwave speed is measured in Hertz (cycles per second).
GAMMA (32 - 64 Hz)
Gamma brainwaves are the fastest of brain waves (high frequency, like a flute), and relate to simultaneous processing of information from different brain areas. It passes information rapidly, and as the most subtle of the brainwave frequencies, the mind has to be quiet to access it. Gamma was traditionally dismissed as 'spare brain noise' until researchers discovered it was highly active when in states of universal love, altruism, and the ‘higher virtues’. Gamma rhythms modulate perception and consciousness, disappearing under anaesthesia. Gamma is also above the frequency of neuronal firing, so how it is generated remains a mystery. The presence of Gamma relates to expanded consciousness and spiritual emergence.
BETA (14 - 32 Hz)
Beta brainwaves dominate our normal waking state of consciousness when attention is directed towards cognitive tasks and the outside world. Beta is a ‘fast’ activity, present when we are alert, attentive, engaged in problem solving, judgment, decision making, and engaged in focused mental activity.
ALPHA (8 - 14 Hz)
Alpha brainwaves are present during quietly flowing thoughts, but not quite meditation. Alpha is ‘the power of now’, being here, in the present. Alpha is the resting state for the brain. Alpha waves aid overall mental coordination, calmness, alertness, mind/body integration and learning.
THETA (4 - 8 Hz)
Theta brainwaves occur most often in sleep but are also dominant in the deep meditation. It acts as our gateway to learning and memory. It is that twilight state which we normally only experience fleetingly as we wake or drift off to sleep. In theta we are in a dream; vivid imagery, intuition and information beyond our normal conscious awareness. It’s where we hold our ‘stuff’, our fears, troubled history, and nightmares.
DELTA (2 - 4 Hz)
Delta brainwaves are the slowest but loudest brainwaves (low frequency and deeply penetrating, like a drum beat). They are generated in deepest meditation and dreamless sleep. Delta waves suspend external awareness and are the source of empathy. Healing and regeneration are stimulated in this state, and that is why deep restorative sleep is so essential to the healing process