The science behind binaural beats occurs naturally in the brain. A different sound (tone) frequency is sent to the left and right ears through headphones.
Upon hearing the two different frequencies, the brain interprets one consistent, rhythmic frequency, known as a binaural beat(s).
The resulting frequency, interpreted by the brain, is the mathematical difference between the two frequencies sent to the left and right ears.
The brain then follows along at this frequency and produces brainwaves of the same frequency.
This theory is known as ‘Frequency Following Response' (FFR); a naturally occurring science that happens in the human brain.
Entraining the brain through sound isn't just a modern trend. It is something that has been part of human societies for centuries.
In this article, we'll step back in time and look at some primitive forms of brainwave entrainment and music therapy. We will also learn how binaural beats were discovered, how they work, and the scientific evidence for their effectiveness.
The Ancient Benefits of Rhythm & Repetition
Although the creation of binaural beats music has only been possible through technological advancement in the last 100 or so years, the use of this type of sound therapy dates back thousands of years.
Ancient cultures were aware of how the brain could be entrained through sound repetition long before modern science was able to prove the process.
History notes many examples of music used as medicine and therapy:
- The ancient Greeks used music to ease stress, promote sleep, and soothe pain.
- The Native Americans and Africans used singing and chanting as part of their healing rituals.
- Even in language we see a connection between healing and music. For example, the Chinese character for medicine includes the character for music (1).
Of course, in times past, societies didn't refer to music therapy, binaural beats, or brainwave entrainment of any kind. But what they did know was that sound had powerful healing properties.
Ancient Beat Rhythms
Interestingly, scientist Melinda Maxfield, PhD, conducted research on the drumbeats used during rituals of ancient cultures and found that they generally beat at a steady rate of 4.5 beats per second.
This consistent beat induced a trance-like state for the tribe, due to the brain following along at a 4.5 beats-per-second brainwave frequency, which is a low Theta brainwave state, as you'll learn about later on.
The pattern of the drumbeat as it relates to beats per second can be correlated with resulting temporary changes in brain wave frequency (cycles per second) and/or subjective experience, provided the drumming pattern is sustained for at least 13 – 15 minutes.
This research supports the theories that suggest that the use of the drum by indigenous cultures in ritual and ceremony has specific neurophysiological effects and the ability to elicit temporary changes in brain wave activity, and thereby facilitates imagery and possible entry into an ASC (altered state of consciousness) (2).
Indeed, in almost every ancient culture, repetitive beat formats have played an important role in wellbeing and prosperity.
For example: through the use of repetitive drumming and chanting, Tibetan monks, Native American shamans, Hindu healers, and master Yogis have been able to induce specific states of being for meditation, transcending consciousness, and healing.
Binaural beats provide benefits in the same way, helping with deeper meditation, stress release, reduced anxiety, improved focus, better sleep, and more.
The Discovery of Binaural Beats
Heinrich Willhelm Dove
The way in which binaural beats work was first discovered in 1839, by a Prussian physicist and meteorologist named Heinrich Wilhelm Dove.
Dove was a keen experimenter, and it was one of his experiments that would pave the way for exploration in the field of brainwave entrainment.
Of course, headphones weren’t available back then, so Dove conducted the following experiment to make his discovery:
Dove had his subject stand in a room. Then, on one side of the room he placed a tuning fork. The fork was connected to a tube that ran to the subject's ear.
Dove then placed a tuning fork on the other side of the room and ran a tube to the other ear.
The forks didn't vibrate at quite the same low frequency, so the subject received different frequencies to the right and left ears.
Dove documented that his subject perceived the effect of the two frequencies combining as a slow beat. We now know this to be the same theory behind the binaural beats phenomena.
Dr. Gerald Oster
Dove made the discovery but didn't connect all the dots.
Indeed, it wasn't until 1973 that biophysicist Doctor Gerald Oster brought binaural beats into mainstream awareness in a paper called ‘Auditory Beats in the Brain' (Scientific American, 1973).
Oster's paper tied-together the different aspects of research that had taken place since Dove's discovery. He gave the subject renewed relevance to modern scientific questions regarding how sound might aid impairments.
Oster viewed binaural beats as having both research value, and as a potential diagnostic medical tool.
In terms of research, he saw the potential for binaural beats to explain features of the auditory system; not least how we locate sounds spatially in our environment and selectively single-out individual sounds from background noise.
From a medical perspective, Oster saw potential to not only diagnose auditory impairments, but to identify a range of seemingly unrelated medical issues.
For example: Oster found strong data that suggested diminished ability to hear binaural beats was an early predictor for Parkinson's Disease.
He also found that variation in the ability to perceive binaural beats correlated subtly with when female subjects were in hormonal cycles.
But central to his thesis, and indeed what sparked renewed interest and research into how binaural beats might help with modern day afflictions such as anxiety, insomnia, pain issues, and memory problems, was that binaural beats involve different neural pathways than conventional hearing, and that listening evokes specific neural responses (3).
Forty nine years on, and lots of research by scientists and music researchers later, binaural beats (brainwave entrainment) music is used by people all over the world to assist in stress and anxiety relief, help with concentration and memory issues, improve sleep, and provide pain relief (4, 5, 6, 7,)
How Do Binaural Beats Work?
The word binaural means “having or relating to two ears”. This represents the process, which works by simultaneously sending a different sound frequency to each ear through headphones.
The entrainment happens inside the brain and is caused by a physiological response.
Upon hearing two tones of different frequencies – sent simultaneously to the left and right ears – the brain perceives a new tone, or third tone, as some refer to it, based on the mathematical difference between the two frequencies.
The brain then follows along at the new frequency and produces brainwaves at the same rate of Hertz (Hz), thus becoming “entrained” to that frequency.
Hertz (Hz) is the way we measure a cycle of sound. 1 Hertz means one vibration cycle per second
For example: If a 200 Hz sound frequency is sent to the left ear, and a 205 Hz frequency to the right ear, the brain will perceive a new frequency at 5 Hz – the difference between the two.
The brain then follows along at the new frequency (5 Hz), producing brainwaves at the same rate of Hertz (Hz). The technical term for this process is ‘Frequency Following Response'.
The brain will only respond in the intended way if it receives the sound frequencies at the same time through headphones. You can test this for yourself using the test tone further down the page.
All you have to do is put on a pair on headphones, relax and press play. It's that easy.
The 5 Brainwave States & Their Benefits
As explained above, we can listen to binaural beats to encourage the brain to produce brainwaves of a specific type (state). There are five main brainwave states, as follows:
- Delta: 1-4 Hz
- Theta: 4-8 Hz
- Alpha: 8-14 Hz
- Beta: 14-30 Hz
- Gamma: 30-100 Hz
The states ascend in terms of speed, starting at the slowest frequency waves, delta, to the fastest frequency waves, gamma.
The effect listening to binaural beats has on your brain is dependent on the frequency of the track and the brainwaves it stimulates production of.
For example: To induce deep relaxation, we can listen to Theta wave music.
And to encourage deeper sleep , we can listen to Delta wave music.
The graphic below shows the five main brainwave state categories used in binaural beats music, and their associated benefits:
The benefits listed under each brainwave state are general associations. It should not be assumed that all frequencies within a state’s range will produce all the listed benefits.
There are specific frequencies associated with specific states of mind, and indeed different results can be experienced in the high, middle, and low areas of each brainwave state.
Test a Binaural Beat for Yourself
Having read the information thus far, you now hopefully understand the theory.
You can test this theory in real-time by using our test tone below.
It is a raw (no music overlay) Theta binaural beat at 6 Hz.
Follow the instructions to complete the test.
- Put your headphones on and press play on the player.
- When you have both earphones in your ears, note that you hear a single pulsating sound. Some liken it to a wavering or trembling type sound.
- Now remove one earphone; left or right, it doesn't matter. When you remove one earphone, you will notice that the pulsation disappears completely and that you hear a single tone in the earphone you still have on.
- When you put the other headphone back in your ear, the pulsating sound comes again. This is because when you have both earphones in, your brain is effectively linking the two frequencies (tones) and perceiving the mathematical difference between the left and right tones (creating a binaural beat). In this case, it perceives a frequency of 6 Hertz.
Please note: When you take one earphone out, move it as far away from your ear as possible.
With some headphones, you may still be able to hear the pulsating sound if the removed headphone is still fairly close to your ear. This is because your brain can still detect the frequency vibration coming from the headphone.
In addition, push the earphone that’s still on your ear firmly to the ear, while moving the other earphone as far away as possible.
Your brain will now follow along and produce brainwaves at the frequency of 6 Hz. This is the ‘frequency following response' process, as discussed earlier.
Note that you should listen for a minimum of 15 minutes to benefit from the entrainment.
Human Hearing Threshold & Binaural Beats
Because the human hearing threshold is commonly cited as 20-20,000 Hz, you may wonder how it is possible to hear binaural beats frequencies below 20 Hz.
This human frequency response refers to the pitch range you can hear: the audible sounds in music.
However, the key thing to remember is that you aren't actually hearing the frequency the brain interprets. What you hear is the initial frequencies sent to your left and right ears.
The binaural beat(s) is the resulting frequency, which the brain interprets after hearing the sound/vibrations of the two frequencies sent to the left and right ears.
The response happens inside the brain. It is often referred to as an auditory illusion: because you don't hear the resulting frequency and the brain is somewhat tricked into responding in this way.
Using the example in the aforementioned section, the brain would produce brainwaves at 6 Hz. This means the brain is perceiving a frequency of 6 vibrations/cycles per second, and subsequently producing brainwaves of the same frequency.
Why Binaural Beats Meditation?
‘Binaural beats meditation’ is our brand name and a term developed for our advanced music therapy. We were the first to coin the term during our research and development.
Not all binaural beats music is designed for meditation and relaxation, but as you can see from the diagram above, many of its use cases are linked to a relaxed, meditative state of mind.
We developed this term for 3 key reasons:
1. Binaural beats music is generally designed to entrain the brain in a similar way to that of meditation; a state often referred to as mindful awareness in the present moment.
2. Our music is accompanied by ambient, relaxing music, often featuring nature-inspired soundscapes. This is similar to the sound design used in standard meditation music.
3. Similar to meditation practice, practitioners are usually seated (sometimes in the lotus position) or lying down. This is conducive to attaining a relaxed, centered state of mind, which is ultimately conducive to entrainment.
We hope you now better understand how binaural beats work. You can get started by compiling your own listening program from our store.