Isochronic tones are used in the process of brain wave entrainment. Brain wave entrainment refers to a method of getting brain waves to sync with a specific stimulus. This stimulus is typically an audio or visual pattern.

Brain wave entrainment techniques, such as the use of isochronic tones, are being studied as a potential therapy for a variety of health conditions. These can include things like pain, attention deficit hyperactivity disorder (ADHD), and anxiety.

What does the research say about this potential therapy? And how are isochronic tones different from other tones? Continue reading as we dive deeper into these questions and more.

Isochronic tones are single tones that come on and off at regular, evenly spaced intervals. This interval is typically brief, creating a beat that’s like a rhythmic pulse. They’re often embedded in other sounds, such as music or nature sounds.

Isochronic tones are used for brain wave entrainment, in which your brain waves are made to sync with the frequency that you’re listening to. It’s believed that syncing your brain waves to a certain frequency might be able to induce various mental states.

Brain waves are produced by electrical activity in the brain. They can be measured using a technique called an electroencephalogram (EEG).

There are several recognized types of brain waves. Each type is associated with a frequency range and a mental state. Listed in order from highest frequency to lowest, five common types are:

  • Gamma: a state of high concentration and problem-solving
  • Beta: an active mind, or normal waking state
  • Alpha: a calm, restful mind
  • Theta: a state of tiredness, daydreaming, or early sleep
  • Delta: a deep sleep or dreaming state

Many isochronic tones are set to music. Here is an example from the YouTube Channel Jason Lewis — Mind Amend. This particular music is meant to ease anxiety.

If you’re curious what isochronic tones sound like on their own, check out this YouTube video from Cat Trumpet:

You may have heard about other types of tones, such as binaural and monaural beats. But how are these different from isochronic tones?

Unlike isochronic tones, both binaural and monaural beats are continuous. The tone isn’t turned on and off as it is with an isochronic tone. The way that they’re generated is also different, as we’ll discuss below.

Binaural beats

Binaural beats are generated when two tones with slightly different frequencies are presented to each ear. The difference between these tones is processed inside your head, allowing you to perceive a specific beat.

For example, a tone with a frequency of 330 Hertz is given to your left ear. At the same time, a tone of 300 Hertz is given to your right ear. You would perceive a beat of 30 Hertz.

Because a different tone is given to each ear, using binaural beats requires the use of headphones.

Monaural beats

Monaural tones are when two tones of similar frequency are combined and presented to either one or both of your ears. Similar to binaural beats, you’ll perceive the difference between the two frequencies as a beat.

Let’s use the same example as above. Two tones with frequencies of 330 Hertz and 300 Hertz are combined. In this case, you’d perceive a beat of 30 Hertz.

Because the two tones are combined prior to you listening to them, you can listen to monaural beats through speakers and you don’t need to use headphones.

It’s thought that using isochronic tones and other forms of brain wave entrainment can promote specific mental states. This may be beneficial for a variety of purposes including:

  • attention
  • promoting healthy sleep
  • alleviating stress and anxiety
  • perception of pain
  • memory
  • meditation
  • mood enhancement

How is all of this supposed to work? Let’s look at a few simple examples:

  • Lower frequency brain waves, such as theta and delta waves, are associated with the sleep state. Therefore, listening to a low frequency isochronic tone might potentially help to promote better sleep.
  • Higher frequency brain waves, such as gamma and beta waves, are associated with an active, engaged mind. Listening to a high frequency isochronic tone could possibly aid in attentiveness or concentration.
  • The intermediate type of brain wave, alpha waves, occurs in a relaxed state. Listening to isochronic tones within the alpha wave frequency may be examined as a way to induce a state of relaxation or aid in meditation.

There haven’t been very many research studies performed on isochronic tones specifically. Because of this, additional research is needed to determine if isochronic tones are an effective therapy.

Some studies have used repeating tones to study brain wave entrainment. However, the tones used in these studies haven’t been isochronic in nature. This means that there was a variation in pitch, in the interval between tones, or in both.

While research into isochronic tones is lacking, some research into the effectiveness of binaural beats, monaural beats, and brain wave entrainment has been performed. Let’s look at what some of it says.

Binaural beats

A 2019 study investigated how binaural beats affected memory in 32 participants. Participants listened to binaural beats that were either in the beta or theta range, which are associated with an active mind and sleep or tiredness, respectively.

Afterward, participants were asked to perform recall tasks. It was observed that people exposed to binaural beats in the beta range recalled more words correctly than those exposed to binaural beats in the theta range.

A 2018 study looked at how low-frequency binaural beats affected sleep in 24 participants. The beats used were in the delta range, which are associated with deep sleep.

It was found that the duration of deep sleep was longer in participants who listened to binaural beats compared to those who didn’t. Also, these participants spent less time in light sleep compared to those who didn’t listen to the beats.

Monaural beats

A 2017 study assessed the effect of monaural beats on anxiety and cognition in 25 participants. Beats were in the theta, alpha, or gamma ranges. Participants rated their mood and performed memory and vigilance tasks after listening to the beats for 5 minutes.

Researchers found that monaural beats didn’t have a significant effect on memory or vigilance tasks. However, a significant effect on anxiety was observed in those listening to any of the monaural beats compared to a control group.

Brain wave entrainment

A 2008 review looked at the results of 20 studies on brain wave entrainment. The reviewed studies assessed the effectiveness of brain wave entrainment on outcomes of:

  • cognition and memory
  • mood
  • stress
  • pain
  • behavior

Although the results of the individual studies varied, the authors found that the overall available evidence suggested that brain wave entrainment could be an effective therapy. Additional research is needed to support this.

There haven’t been many studies into the safety of isochronic tones. However, there are a few things you should keep in mind before using them:

  • Keep the volume reasonable. Loud noises can be harmful. Noises above 70 decibels over a prolonged period of time can cause hearing damage. For example, normal conversation is about 60 decibels.
  • Use caution if you have epilepsy. Some types of brain entrainment may cause seizures.
  • Be aware of your surroundings. Avoid using the more relaxing frequencies when you’re driving, operating equipment, or performing tasks that require alertness and concentration.

Isochronic tones are tones of the same frequency that are separated by short intervals. This creates a rhythmic pulsing sound.

Isochronic tones are used in the process of brain wave entrainment, which is when your brain waves are deliberately manipulated to sync with an external stimulus like a sound or image. Other examples of auditory entrainment types are binaural and monaural beats.

Like other types of brain wave entrainment, using isochronic tones could potentially be beneficial for a variety of health conditions or for enhancing mood. However, research into this area is currently very limited.

More research has been performed into binaural and monaural beats. So far, it indicates that they may be beneficial therapies. As with isochronic tones, further study is necessary.