The Science


Brainwave Frequencies & Effects 

As is well known, brainwaves can be altered by various extrenal stimuli, including auditory stimulation.

One of the functions of SmartSound is to promote broad-spectrum, evidence-based benefits and effects via the use of rhythmic auditory stimulation and other techniques to stimulate targeted brainwave frequencies.

Those who have tried Mini-D-Stress for example, will have likely have noticed some interesting (and hopefully enjoyable) effects in this regard.

At a glance, here are some of the benefits and functions associated with key brainwave frequencies

  • Gamma: learning, concentration, and self-control 
  • Beta: increased energy levels, focus, alertness and clear thinking
  • Alpha: help with tension headaches, memory, mild-anxiety and creative flow states
  • Theta: may assist emotional processing, deep relaxation, intuition, memory consolidation
  • Delta/sub-delta: may assist pain relief, immune function, healing and deep sleep

For more detailed information please read below.


Additional information

For the benefit of SmartSound users, we have presented some general findings regarding brainwave frequencies drawn from clinical trials and research. It includes brainwave frequency stimulation using visual and/or auditory stimulation.

While this is primarily for educational purposes, it may also help those using our technologies to better understand some of the more general effects and benefits they experience.

Although exact frequency thresholds are still debated by researchers, those below are generally representative to within a few Hertz. (For simplicity we have excluded lambda, mu and epsilon frequencies).

Some academics also note that, while this is a convenient means of classification, it doesn't take into account the highly complex, largely unknown interrelationships that exist between frequencies. The study of brainwaves is very much an evolving field.


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 have used gamma frequency stimulation to assist 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 most SmartSound protocols, and may be nested or 'coupled' with other frequencies.


Beta: ~ 15 – 38 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 usually 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 possibly, 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 activity often produces 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. Some consider 18.5 Hz in particular to be 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 ‘burnout’.  

In clinical applications, Beta 1 and 2 brainwave stimulation has 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 the Mu wave and ‘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 fit 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 by clinicians to assist with concentration, reading speed and energy levels as well as for help with epilepsy, ADHD, insomnia, depression, anxiety, stress and autism. It may also be particularly helpful for those lacking in physical fitness or exercise.


Alpha: ~ 7.5 – 12.5 Hz  

Information processing; relaxed, tranquil consciousness and inward awareness; creative flow states; the coalescence of different frequencies; improved 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 for stress, anxiety, drug and alcohol addiction, depression, ADHD, autism, PTSD (thought to block alpha activity), peak performance and headache relief.  At, or close to 10.2 Hz, it has proven helpful for seniors (who usually experience a slowing of alpha frequencies as they age), and facilitating memory in both younger and older adults.

Alpha frequencies also have a long association in sports psychology and personal development for enhanced visualisation, meditation, internal goal setting processes and 'flow states'.

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 stimulation has also been shown to assist with emotional stability, reductions in cortisol (a major stress hormone), serotonin production and significant improvements in heart rate variability (HRV). Other studies suggest frequencies at the alpha/theta threshold promote the most cerebral blood flow.

Alpha frequencies are included in nearly all SmartSound protocols.


Theta: ~ 4 – 7.5 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 - which is associated with the highly suggestible 'hypnagogic trance' -  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 most 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.

Pronounced theta activity while awake during the day however is considered abnormal in healthy adults, and may be indicative of slow wave conditions like depression, ADD/ADHD and PTSD.

Nonetheless, it's perfectly normal in young children from 2-6 where it facilitates their rapid learning abilities and vivid, creative imaginations. It's during their highly suggestible 'theta years' that a child's fundamental, life-shaping beliefs, experiences and assumptions about the world are 'programmed' into their subconscious. 

That's why loving, positive early parenting and safe, supportive environments are absolutely vital for their best future - and ours!

The theta bandwidth is used extensively in our deep relaxation and sleep protocols.


Delta & Sub-Delta:~ 0.5 – 4 Hz

Deep dreamless sleep, immunity, 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 are known 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.

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 (GHB), 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, the clinical use of delta and sub-delta brainwave stimulation is primarily used for stress and sleep related issues like insomnia, as it is with SmartSound.


So now we’ve come full circle in our exploration of brainwave frequencies.

We hope you enjoyed the trip!



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