The Science


Brainwave Frequencies and Effects 

Below is a basic summary of recent brainwave research and some of its clinical applications. It's intended for general educational purposes only and to help explain some of the principles underlying SmartSound™.

Please note that exact frequency thresholds are still debated by researchers, but those we've provided are generally representative to within a few Hertz. 

Some academics also note that, while this may be a convenient means of classification, it doesn't take into account the highly complex, largely unknown interrelationships that exist between frequencies.

To keep things simple, a useful analogy for understanding brainwaves is to think of the sea, with many waves, large and small, in constant interaction.


Lambda ~ 100 Hz +   

Largely unknown but may include brain timing, higher states of awareness and 'super-normal' abilities

Lambda extends into the upper range of observable biological brain rhythms, currently around 200-600 Hz, in the so called 'ripple range' - as opposed to actual 'waves'. (Think of our sea analogy again). Little is known about this frequency range and much remains speculative at this time. 

Some researchers believe it may play a role in brain timing. Others suggest it may be linked to states of higher consciousness and ‘super normal’ phenomenon like out of body experiences (OBE’s). What is known for sure is a surprising link between these, our highest, and our lowest brainwave frequencies. (See epsilon below).


Gamma: ~ 38 – 100 Hz

Integration/synchronization of brain centres involved in learning, memory, thought generation, task processing, motor function and sensory binding; heightened creativity, comprehension, concentration and impulse control

Many researchers consider this high frequency brainwave to be the key to cognition and the brain’s optimal frequency of functioning - especially at 40 Hz. Gamma is thought to act as a binding mechanism that holographically synthesizes and unifies data throughout the brain, analogous to the 'oil in an engine' integrating other functions.

Research has linked gamma frequencies to higher mental functioning, self-awareness, self-control, problem solving, language development in children, memory, and many aspects of heightened consciousness and perception. In fact, as gamma activity is known to disappear during anaesthesia, it may be essential to consciousness itself.

Those with low gamma activity have been found to be more prone to depression, stress and unfocused or impulsive thinking. Clinicians are reporting success using gamma in the treatment of language and learning disabilities (especially in children), depression, ADHD, Alzheimer’s (those with this disease typically produce very little gamma activity), and even autism.

Gamma may be present in virtually all areas of the brain in both adults and children and is known to occur when we are simultaneously processing information in both hemispheres, during REM, the formation of new brain circuits and in ‘bursts’ during auditory and other forms of sensory processing.

Significantly higher than normal resting levels have been noted in the frontal lobes of Buddhist monks with extensive ‘loving kindness meditation’ experience - which also suggests neuroplastic change from long term training.

Whales and dolphins are also known to operate in this frequency.

Gamma frequencies are included in many SmartSound™ protocols and may be nested or 'coupled' with other frequencies.


Beta: ~ 15 – 40 Hz

Focused, analytical, rational, wide awake, alert awareness; concentrated, focused mind, heightened sensory perception, emotional stability, visual acuity, cognitive control of motor activity

Beta is a ‘fast’ higher frequency bandwidth typically associated with outward awareness, full alertness and rapid thought generation. Beta production begins at around 12 years of age and is most likely your dominant frequency right now as you’re reading this.

Clinical studies of beta 2 (see below) link it to full awareness of self and surroundings, energy, alertness, activity, increased mental ability and focus, peak states of concentration, motivation and even visual acuity. It’s also been associated with IQ increase, perhaps in a similar manner to 'smart drugs' or nootropics, by stimulating overall brain activity.

Beta is usually responsible for the overactive “chatter-box/ monkey-mind” that prevents us from sleeping.

Those with ‘slow wave’ conditions like ADD, ADHD and depression typically exhibit low waking beta wave activity and may be prescribed stimulants to increase daytime beta activity and/or block slower frequencies.

The beta range falls into three classifications:  

• Beta 1 (~12.5 Hz – 15 Hz): Slow or Low Beta wave activity. (See SMR below).

• Beta 2 (~ 15 Hz – 23 Hz): This mid-range beta is frequently used by clinicians. 18.5 Hz in particular is considered an optimal frequency for focus and concentration.

• Beta 3 (~ 23 Hz – 40 Hz): This fast beta activity, especially in its higher range has been associated with hyper-arousal/hyper-vigilance, anxiety, stress, paranoia, excessive energy and ‘burn-out’.  

In clinical applications, Beta 1 and 2 have been used to promote wakefulness and alertness, focus, mood elevation, general cognitive performance and for assistance with depression and ADHD.


Sensorimotor Rhythms (SMR): ~ 12.5 – 15 Hz

Physical and mental calm; non-impulsive, external awareness; improved energy levels; flow states; healthy sleep patterns

SMR rhythms are associated with ‘flow states’ that are relaxed yet alert, focused and attentive - some researchers refer to them as an 'idling' rhythm. They occur most notably when the body is inactive after physical exercise, and in clinical trials, have proven helpful in assisting with sleep related problems including restless leg syndrome.

High SMR levels have been noted in athletes and other physically healthy people, which may also account for their generally healthy sleeping patterns, while those with insomnia often exhibit lower than normal levels. 

SMR brainwave stimulation has been used successfully by clinicians to assist with concentration, reading speed and energy levels as well as for help with insomnia, depression, anxiety and stress. It may be particularly helpful for those lacking in physical fitness or exercise and is featured in several of our protocols.


Alpha: ~ 7.5 – 12.5 Hz  

Information processing; relaxed, tranquil consciousness and inward awareness; creative flow states; the coalescence of different frequencies; enhanced HRV, serotonin production, memory and dream recall; reactivity to disturbing noises in sleep

Alpha activity begins at around the age of 6 years. In adults it produces a characteristic calm, creative 'flow-state' state when we close our eyes and begin to withdraw from external sensory stimulation such as when 'day dreaming'. It's often referred to as the bridge between waking and sleeping.

Alpha activity may be more pronounced in creative, artistic and entrepreneurial people. It has been linked with the ‘aha’ experience of creative insight and ‘out of the box’ thinking. EEG monitoring of Alfred Einstein showed he produced consistent alpha-band activity while solving complex mathematical tasks.

Studies suggest that while upper or mid-range alpha may assist with these kinds of activities, its lower range may be counterproductive for highly attentive, focused critical thinking or technical, detail orientated work.

Alpha stimulation has a long and successful history of clinical applications including for stress, anxiety, drug and alcohol addiction, depression, ADHD, autism, PTSD (thought to block Alpha activity), peak performance and headache relief.  10 Hz stimulation has proven helpful for seniors, who are otherwise prone to a slowing down of alpha frequencies as they age, and 10.2 Hz specifically has been associated with improved memory.

The alpha frequency band has also had a long association with sports psychology and personal development for enhanced visualisation, meditation, internal goal setting processes and 'flow states'.

It's also associated with emotional stability, reductions in cortisol (a major stress hormone), serotonin production and significant improvements in heart rate variability (HRV). Some studies suggest frequencies at the alpha/theta threshold promote the most cerebral blood flow.

As a point of interest, sports professionals have been observed producing a surge of alpha in their left hemisphere just prior to a successful move or strategy - and a corresponding surge of beta when they fail! Likewise, Einstein was also observed to drop out of alpha-band activity into beta whenever he realised an error in his calculations.

Alpha frequencies are included in most of our protocols.


Theta: ~ 4 – 8 Hz

Memory consolidation; creativity, imagery and visualization; free-flowing lucid thought; spatial navigation tasks; inspiration and intuition; REM; processing of new (episodic) information; emotional processing and heightened suggestibility.

Theta production begins at around 2 years of age. Arising from the right hemisphere and the deeper subcortical regions of the brain, theta frequencies have long been considered the ‘doorway to the subconscious’.

These sleep inducing, low-frequency brainwaves have been associated with deep relaxation, creativity, memory consolidation, emotional processing, vivid imagery, extrasensory perception, intuitive insights, REM states and a great deal of other subconscious activity and phenomena.

Hypnotherapists in particular consider theta to be the optimal state for accessing the right hemisphere and changing unwanted subconscious behaviours and programs, the reception of information beyond normal waking consciousness, and the gateway for learning and memory. Deeply suppressed emotional material and childhood memories appear to be more readily accessed and released in theta under expert guidance. 

Dominant in very deep meditation, prayer, hypnotic trance and REM states, theta is also associated with enhanced immune function and neurochemicals including vasopressin and catecholamine. These factors, combined with its ability to reduce stress levels, induce deep relaxation and lower arousal, have given it a reputation as a key 'healing frequency'.

Pronounced theta activity while awake however is considered abnormal in healthy adults, and may be indicative of  ‘slow wave’ conditions like depression, ADD/ADHD and PTSD. However, it's perfectly normal in younger children from 2-6 which accounts for their heightened uptake of information, rapid learning and vivid, creative imaginations. 

The theta bandwidth is used extensively in our deep relaxation and sleep protocols. However, we caution against overuse during the day as it may produce drowsiness and should therefore be avoided, especially by those with slow wave conditions - unless they intend to sleep.


Delta & Sub-Delta:~ 0.5– 4 Hz

Deep dreamless sleep, immune enhancement, regeneration and healing; anti-ageing hormones, cortisol reduction and  pituitary release of H.G.H.; extremely deep relaxation

Delta waves are present at birth and have been shown to persist in the waking state of children to around 5 years. Both delta and sub-delta are vital for deep, restorative sleep and its many associated benefits.

During production of these very low frequency, high amplitude brainwaves we’re usually completely unconscious and catatonic in non-REM sleep stages 3 and 4. However, brain scans have shown that some advanced meditators, such as yogis and monks, can enter delta states and remain there with full conscious awareness. (Also see epsilon below)

Delta has been associated with physical/emotional healing and immune functioning, memory consolidation, the production of anti-ageing hormones including DHEA and melatonin, significant stress reduction (calming of the limbic system) and the lowering of cortisol.

It has also been linked to pituitary release of trace amounts of human growth hormone (H.G.H), gamma - hydroxybutyric acid (GBA) with its neuro-protective qualities, and of course the many essential benefits of a good nights sleep - which include accelerated muscle repair and optimal fat burning!

Delta production typically declines with age and, by adolescence, levels may decrease by about 25%. Seniors and the elderly may produce very little delta activity during sleep.

Studies suggest delta is typically under-produced in chronic stress or sleep conditions (including those who choose voluntarily sleep curtailment), and that a lack of this frequency may play a role in Parkinson’s disease, diabetes and schizophrenia.

Not surprisingly, clinical use of delta and sub-delta brainwave stimulation is primarily related to stress and sleep related issues like insomnia, as it is with SmartSound™.


Epsilon < 0.5 Hz

Super normal abilities, expanded consciousness, ‘suspended animation’ with no perceivable heartbeat, respiration or pulse

Last but not least, at the lowest, slowest end of the frequency spectrum are the mysterious and little understood epsilon brainwave frequencies.

These are thought to produce much the same phenomena as the super high-frequency lambda waves at the top of our list. Researchers have noted that if you zoom in on the big, slow epsilon waves you’ll see within them a modulation frequency of 100-200Hz - or lambda! Or, to put it the other way, if you zoom out from lambda’s super fast 100-200 Hz waves you’ll see them ‘riding’ on the crest of super slow epsilon waves. Waves upon waves.

Some researchers believe epsilon frequencies may also be involved in the advanced yogic state known as ‘suspended animation’ where they exhibit no perceptible heartbeat, respiration or pulse yet remain fully aware and profoundly relaxed.

Although we incorporate epsilon into our sleep protocols, you’re highly unlikely to enter into a state of suspended animation!


So now we’ve come full circle in our exploration of brainwave frequencies. We hope you enjoyed the trip!



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