Brainwave Entrainment

2023 UPDATE: For our complete guide to brainwave entrainment, go here.

Brainwave entrainment is a process that uses sound or images to alter one’s brainwaves, usually attempted with the use of specialized software. The entrainment is often aural, as in the case of binaural and isochronic tones, or else visual, as with a dreamachine, or a combination of the two with a mind machine.

Brainwave entrainment refers to the brain’s electrical response to rhythmic sensory stimulation, such as pulses of sound or light. Audio/visual entrainment is when sound and light is used together. When the brain is given a stimulus, through the ears, eyes or other senses, it emits an electrical charge in response, called a cortical evoked response. These electrical responses travel throughout the brain to become what you see and hear.

When the brain is presented with a rhythmic stimulus, such as a EOD from an electric fish, the rhythm is reproduced in the brain in the form of these electrical impulses. If the rhythm becomes fast and consistent enough, it can start to resemble the natural internal rhythms of the brain, called brainwaves. When this happens, the brain responds by synchronizing its own electric cycles to the same rhythm. This is commonly called the frequency following response.

Benefits of Brainwave Entrainment

There’s an enormous amount of mental benefits that can be experienced from brainwave entrainment, some of which are:

  • Enhanced sleep and ease of getting to sleep.
  • Increased learning ability and memory.
  • Behavior modification (getting rid of your bad habits).
  • Enhanced health.
  • Increased creativity and problem solving ability.
  • Relaxation and stress reduction.
  • Help with ADD/ADHD.
  • Access your intuition.
  • Increase your focus and concentration.
  • Deepen your spiritual connection.

Understanding Brainwaves

Overall brain activity has a pulse, a beat — just like the heart. Except unlike the heart, the brain pulses very quickly — anywhere from 3 times per second to 100 times per second. These brain pulses, or brainwaves, happen at a variety of speeds. During deep sleep, for example, the brain pulses about 3 times per second. During high-focused thinking, the brain might pulse as much as 50 times a second.

Different brainwave frequencies have been shown to correspond to different “states of mind”. Brainwave frequency seems to correspond to a spectrum of subjective experience. Slow brainwaves feel more relaxing and introspective. Fast brainwaves can be a sign of concentration or stress. Although brainwave frequencies exist across a wide range, we generally classify them into 5 groups (from slow to fast): delta, theta, alpha, beta, and gamma.

States of Consciousness

Brainwaves fastest to slowest:

  • Gamma – Associated with enhanced perception and a high level of consciousness
  • Beta – Dominant rhythm when awake, alert or anxious, with eyes open
  • Alpha – Relaxed alertness; normally is induced by closing the eyes and relaxing
  • Theta – Drowsiness, first stage of sleep; not common in awake adults, but common in daydreaming children
  • Delta – Deep sleep

Brainwave Entrainment with Binaural Beats & Isochronic Tones

Binaural beats are the most popular form of brainwave entrainment. Many meditation CDs have them in the background. Binaural beats require headphones because they working using two separate tones, played differently into each ear. The tones then create a pulse, or “beat.” Users will not notice the separate tones because it is all done very fast.

If a person wished to enter the alpha state for some relaxation, he or she could not just create a 7 Hz audio tone and listen to it on headphones. The lowest key on the piano is 27.5 Hz. A person’s ear cannot hear audio tones below about 20 Hz. One trick to get the brain to “hear” 10 audio pulses per second or lower is to use a trick called “binaural beats”. To give an example with headphones, the left headphone plays a 500 Hz tone, the right a 510 Hz tone. By mixing the two together your brain perceives the difference — a 10 Hz tone. Now there is an audio pulse going at “alpha frequency” and the brainwaves will try to slow down to match up. The end result in this case is that the person feels calm and relaxed.

Isochronic tones do not require headphones. Only one tone is used, but it is manually spaced to turn on and off in a particular pattern. This makes it more effective because the brain doesn’t have to do the extra work of putting the two tones together. The Isochronic tone technology has been fully tested and is proven to work.

In 1999, the Journal of Neurotherapy published a case study conducted by Thomas Budzynski, Ph.D. He tested 8 struggling college students. Tests were performed using both visual and audio brainwave stimulation, the students significantly increased their grade point average, and their GPA continued to rise even after treatment was discontinued. Isochronic tones reduce stress and have all of the benefits of binaural beats, but they use monaural and isochronic tones for what the creator, Morry Zelecovitch calls “brainwave entertainment.

Some Interesting Facts on Brainwaves

  • Trained musicians experience states of gamma while listening to music. While non-musicians do not.
  • Although delta waves usually correspond to the unconscious state of deep sleep, highly experienced meditators have been shown to attain conscious awareness during the delta state.
  • Using a cell phone increases alpha activity in the brain. Studies have even shown that using a cell phone on, say, your left ear, will increase alpha activity most predominately in the brain regions on the left side.
  • Cell phone usage close to bedtime has been linked to mild insomnia.
  • Doing brain exercises during the day has been shown to increase delta brainwave synchrony during slow-wave sleep at night.
  • Delta frequencies have been shown to increase production of the hormones DHEA and melatonin. DHEA is a precursor to testosterone, perhaps your body’s most potent energizer hormone (for both men and women). This is one of the many reasons why high quality deep sleep increases feelings of natural energy and vitality during the day.
  • Your brain naturally cycles through the brainwave states during the day. Every 90 minutes or so, your brain will require a break and slow down its activity, possibly entering alpha or even theta states. This cycle is known as the ultradian rhythm, or basic rest and activity cycle (BRAC).
  • Alpha and theta states help reset sodium/potassium balance in the brain — without proper sodium/potassium balance, neurons can’t fire.