The brain does not operate in just one single frequency; the full spectrum of brainwave frequencies are always running, all the time. The dominant frequency determines our mental state – and entrainment temporarily shifts our mental state by boosting one frequency to be louder than the others.

Brainwave Entrainment

The Hype

There is a lot of marketing hype around brainwave entrainment. It is sold with promises of increasing IQ, promoting weight loss, ‘mind-tripping’, enhancing creativity, concentration, inducing spiritual states and more.

While these claims are not entirely true, they are not altogether false either. In practice, the claims are based on an overly-simplistic view of how the brain and the brainwaves function.

The Reality

People are very seldom deficient in a certain brainwave type in all areas of their brain. Usually the distribution is much spottier, with an excess in one area and a deficiency in another.

We are all different, especially when it comes to the distribution of our brainwaves. Boosting a certain brainwave state may be beneficial for one person, and emotionally uncomfortable for another. Without knowing each person’s starting position, entrainment can be rather ‘hit and miss’.

If brainwave entrainment leaves you with unwanted side-effects (see below) or discomfort, you’re probably encouraging a range of brainwaves that are already excessive in some area of your brain. The way around this is to get a brain map to see what your brain’s strengths and weaknesses are, and see what (if any) brainwaves could use some encouragement.

Types Of Brainwave Entertainment

There are a number of different methods available, each with its own pros and cons.

Music Modulation

Most audio brainwave entrainment is ‘embedded’ into musical soundtracks to enhance the listening experience. Any full spectrum soundtrack can be used, from a symphony to nature sounds to simple background noise.

Music modulation allows for higher intensity levels than with beats alone.

Gamma brainwaves

Monaural Beats

Monaural brainwave entrainment is a single pulsing beat. It can be heard as a ‘click’ or pulse in the music, created by the convergence of two tones emanating from a single speaker.

Monaural beats are considered to be more effective than binaural beats, however they can more easily interfere with any music they are embedded in.

Monaural beats are used without headphones.

Gamma brainwaves

Binaural Beats

When we hear a sound, we locate the direction it is coming from by detecting the minute the tone differences between each of our ears. Our brainwaves begin to pulse (phase resonance) at the difference between the tones, and using this ‘phase difference’ we detect the direction of the sound.

Binaural beats ‘trick’ this direction finding system by playing a different tone in each ear; for example, if a 300Hz tone is played on one ear, and a 312Hz played in the other, your brainwaves will begin to resonate at the difference between the tones (12Hz, below normal hearing range).

While not quite as effective as monaural beats, binaurals aren’t as noticeable to the ear and improve the listening experience.

Because different tones are played to each ear, headphones are needed for it to be effective. Binaural beats played through loudspeakers become monaural beats.

Gamma brainwaves

Isochronic Beats

Often used in combination with monaural and binaural beats, isochronic tones are regular beats of a single tone embedded into a narrow audio bandwidth of the music itself. One frequency band of the music oscillates, leaving the rest of the music untouched.

Isochronic tones are considered the most effective form of audio entrainment, and make for the most pleasant listening experience. If done well, the tones are not noticeable to the ear.

Gamma brainwaves

Sound and Light

With so much of the human brain dedicated to vision, sound and light brainwave entrainment (aka. audio-visual entrainment (AVE), light and sound machines, photic entrainment or mind machines) is far more powerful and much faster acting than audio beats alone. It can elicit a brain response in seconds.

Sound and light brainwave entrainment uses monaural, binaural, or isochronic beats, along with glasses fitted with diodes (or a computer screen) that flash in time with the audio beats.

Sound and light entrainment is quite forceful. Start slow and work your way up, DO NOT overdoo it. Use with due caution.

Gamma brainwaves

EEG Active

EEG active entrainment is sound and/or light entrainment which changes according to what is happening in your brain at any given moment. The EEG brainwave sensors monitor your brain activity in real-time, and alters the entrainment to suit.

Though the equipment is similar, EEG active entrainment is not to be confused with neurofeedback. Neurofeedback encourages you to change your brain activity yourself rather than ‘pushing’ it there with brainwave entrainment.

Gamma brainwaves

Electromagnetic (EM)

As with most things, there is an exception to the rule – and that is EM entrainment. Some consider it a form of entrainment; others consider it something else entirely. Either way, it is worth a mention.

Electromagnetic entrainment does not use sound or light. It uses small pulsing electromagnetic fields (at about the same intensity as a large headphone speaker) to directly interact with the neurones.

Brainwaves themselves are electromagnetic in nature. As EM entrainment uses the same method as the brain itself, it is very fast acting (the brain responds in milliseconds). Most importantly, electromagnetic entrainment is region specific, meaning that you can train brainwave frequencies in a certain spot (rather than having to train globally over the entire cortex as with sound and/or light entrainment).

At its best, EM entrainment is used in combination with EEG equipment for real-time monitoring. The EEG can check the brain’s response to each pulse, and shift the frequency as required. It can help ‘un-stick’ stubborn mental patterns, or encourage activity in one area while leaving the others alone. It is quite an advanced tool (see Neurofield).

This is the only type of entrainment that we use clinically.

Gamma brainwaves

The History

Brainwave entrainment is nothing new. Ceremonial chambers acoustically tuned to specific brainwave frequencies have been found dating back to the Bronze Age, and the ancient Greeks used flickering sunlight shining through a spinning wheel to induce altered states.

Since the 1970s, a wealth of brainwave entrainment techniques have developed using digitally encoded audio beats, strobe lights, or low-energy electromagnetic fields.

Do We Use It?

We rarely use brainwave music therapeutically; it is rather an imprecise tool compared to other brain training methods.

Both brainwave entrainment and neurofeedback deal with brainwaves, but the similarity stops there. Entrainment pushes your whole brain into a pre-determined state, while neurofeedback teaches you how to move specific parts of your brain on your own. It is the difference between forcing the brain into a given position, and skills building so you can move it there yourself.

The Warnings

A Japanese television station broadcast a light and sound ‘strobe effect’ as part of a cartoon in 1997. In only 5 seconds, it put 700 children into hospital with seizures, and untold thousands more experienced headaches, dizziness, and nausea.

As learned from Japanese cartoons, do not use brainwave entrainment if you are prone to seizures (or if you’re pregnant, in case you are prone to seizures and unaware of it). Take extra caution if under 26 years of age, as the brain is still developing and is more sensitive.

If the following general guidelines are followed, it will greatly limit your risk of discomfort.

  • Don’t overdo it; most cases of side-effects come after overuse. A fifteen minute session is sufficient to begin (or 3-5 minutes if using audio/visual entrainment). Everyone reacts differently, and you will need to determine your sensitivity before jumping in.
  • If you experience increased anxiety, convulsions, overwhelming subconscious images, nausea, headaches, dizziness or increased heartbeat, discontinue use immediately and permanently.
  • Do not use brainwave entrainment if you have any brainwave hyper-arousal or instability symptoms.

The warnings done, it must be said that the vast majority of people have no ill-effects from brainwave entrainment. The most common side-effect is simply feeling a little unusual for a while. If you happen to experience any unwanted effects, discontinue use, give it a few days, and you will return to normal.

Brainwave entrainment is a method to stimulate the brain into entering a specific state by using a pulsing sound, light, or electromagnetic field. The pulses elicit the brain’s ‘frequency following’ response, encouraging the brainwaves to align to the frequency of a given beat.

This ‘frequency following’ response of brainwave entrainment can be seen in action with those prone to epilepsy. If a strobe flashes at their seizure frequency, the brain will ‘entrain’ to the flashing light, resulting in a seizure.

On the positive side, this same mechanism is commonly used to induce many brainwave states; such as a trance, enhanced focus, relaxation, meditation or sleep induction. The brainwave entrainment effectively pushes the entire brain into a certain state.

Brainwave entrainment works for almost everyone. It is a great way to lead your mind into states that you might usually have difficulty reaching, allowing you to experience what those states feel like.

Any stable frequency evokes a cortical response. The brain synchronises its dominant brainwave frequency with that of the external stimulus. This is called Brainwave Entrainment.