The Science


Brainwave Frequencies and Effects 

Below you'll find a simplified exploration of some of the latest findings concerning brainwave frequencies, plus some of their clinical applications to help you better understand how brainwave stimulation may assist with various conditions and issues. 

Although their exact frequency thresholds are still debated amongst researchers, those given below are generally representative to within a few Hertz. 

While it's a convenient way to classify these frequencies, the reality is that they exist in complex interrelationships and synergies. And, as some researchers point out, strictly defined frequency bands ignore the important interplay between frequencies.


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 the surface of the ocean as a useful analogy). 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

This high frequency brainwave is considered by Nobel Prize winner Sir Francis Crick and many others 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' that integrates all 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, and its generation of compassion - 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 also be nested or 'coupled' with other key 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. It’s most likely your dominant frequency right now as you’re reading this.

You can think of it as the brainwave equivalent of a stimulant like Adderall, Ritalin or caffeine – or other chemicals associated with increased Beta activity. It’s also typically involved in the “chatter-box/ monkey-mind” that prevents you from sleeping.

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 indirectly associated with IQ increase in much the same way as 'smart drugs' or nootropics are supposed to, by stimulating overall brain activity.

Those with ‘slow wave’ conditions like ADD, ADHD and depression typically exhibit low Beta wave activity and may therefore 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): These mid-range Beta waves are the ones most 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 around the high 20’s – mid 30’s has been associated with hyper-arousal/hyper-vigilance and therefore anxiety, stress, paranoia, excessive energy, and ‘burn-out’. ‘Road rage’ or similar angry outbursts may correlate to a spike of Beta 3. Not surprisingly it is usually avoided by clinicians.  

Based on clinical trials and research, we include Beta 1 and 2 in various 'stimulation' sessions to promote such things as wakefulness and alertness when tired, focus when preparing for demanding mental tasks like exams or job interviews, mood elevation, general cognitive performance and assistance with depression and ADHD. Some of the other benefits mentioned above may also occur.


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.

Research shows that high SMR levels often occur 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 is also thought to be particularly helpful for those lacking in physical fitness or exercise.

The SMR frequency band is often included in SmartSound™ 'stimulation' protocols, either in dedicated form or as an adjunct to other frequencies.


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 produces a characteristic calm, creative 'flow-state' state when we close our eyes and begin to withdraw from external sensory stimulation. And, although it may be present to some degree during normal waking consciousness -especially during 'day dreaming', it's often referred to as the bridge between waking and sleeping.

Research indicates that Alpha activity is typically high 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. Alpha at 10 Hz in particular, is also proving helpful for seniors who often exhibit a slowing down of Alpha frequencies as they age. At 10.2 Hz it has been associated with improved memory. Alpha also appears to be linked to both the suppressive and selective functions of attention. Some studies suggest frequencies around the Alpha/Theta threshold promote more cerebral blood flow than any others.

Additionally, the Alpha frequency band has long been used for personal development applications like enhanced visualisation, meditative and internal goal setting processes. It has also been associated with emotional stability, reductions in cortisol (a major stress hormone), serotonin production, enhanced memory, significant improvements in heart rate variability (HRV), ‘flow states’ in sport and other activities.

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 and into Beta whenever he realised an error in his calculations.

Key Alpha frequencies form an important element in many of our protocols, ranging from dedicated Alpha sessions for specific purposes to more generalised use in sleep or relaxation sessions.

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.

Descending from Alpha, we enter Theta and the deeper subcortical regions of the brain. Arising from the right hemisphere Theta frequencies have long been viewed as the ‘doorway to the subconscious’, involved in REM dream states and very deep relaxation.

Generally classed as ‘slow wave’ activity, these sleep inducing, low-frequency brainwaves have been associated with creativity, memory consolidation, emotional processing, vivid imagery, extrasensory perception, intuitive insights and a great deal of other subconscious activity and phenomena.

Many therapists- and hypnotherapists in particular, consider working with clients in 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 also appear to be more readily accessed and released in Theta under expert guidance. 

Dominant in very deep meditation and contemplative prayer, hypnotic trance and REM states, Theta is also associated with the production of many vital neurochemicals including vasopressin and catecholamine as well as enhanced immune functioning. These factors, combined with its ability to reduce stress levels, induce deep relaxation and lower arousal, have led some clinicians to consider Theta as an ideal 'healing' frequency.

It should be noted however that pronounced Theta activity while awake is considered abnormal in healthy adults, and is often indicative of  ‘slow wave’ conditions like depression, ADD/ADHD and PTSD. However, it's perfectly normal in younger children and may help account for their heightened uptake of information and rapid learning, vivid, creative imaginations – and impulsivity. 

While the Theta bandwidth is used extensively in our deep relaxation and sleep protocols, overuse during the day may produce drowsiness and should 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 and Sub-Delta are vital for deep, restorative sleep and its many associated benefits. When we’re producing 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 yogis and monks can enter Delta in meditation states and remain there with full conscious awareness. (Also see Epsilon below)

For the average person however, there are many vital  benefits associated with optimal Delta activity including; enhanced physical/ emotional healing and immune functioning, the production of anti-ageing hormones including DHEA and melatonin, significant stress reduction (calming of the limbic system) and the lowering of cortisol.

Research also links Delta frequencies 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 gradually declines with age. Newborns and infants are Delta dominant even when awake, but by adolescence levels typically decline by about 25%. Seniors and the elderly may produce very little Delta activity, even during sleep.

Studies show it’s typically under-produced in chronic stress or sleep conditions and in those who choose voluntarily sleep curtailment - depriving them of its restorative benefits for optimal functioning and regeneration. Not surprisingly, clinical use of Delta brainwave stimulation is primarily related to stress and sleep related issues like insomnia.

Other conditions where the under-production of Delta is believed to play a role include Parkinson’s, diabetes and schizophrenia, while adults with significant waking Delta activity may experience learning disabilities or ADHD/ADD. 

Both Delta and sub-delta may be included in our deeper relaxation protocols, and of course are used extensively for their essential role in all of our sleep sessions.


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.

Remarkably, these are thought to produce much the same phenomena as the super high-frequency Lambda waves at the top of our frequency list. Interestingly, 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 of consciousness known as ‘suspended animation’ where they exhibit no perceptible heartbeat, respiration or pulse yet remain fully aware and profoundly relaxed. This is presumably similar to the super deep Delta meditative states mentioned above.

Although we like to incorporate at least some Epsilon into our sleep session 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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