Holosync “binaural beat” meditation CDs

Brain entrainment products such as Holosync®, EquiSyncTM, Hemi-Sync® and many others create sound frequencies called “binaural beats,” said to influence the brain by altering one’s brain wave patterns. Companies promoting entrainment products—usually in the form of CDs or downloads—claim that listening to these sounds produces a range of benefits, such as an “instantly induced, advanced meditative state,” synchronization of the brain’s left and right hemispheres, better sleep, improved learning and reduced stress.

How is entrainment different from the Transcendental Meditation technique?
Holosync and other such products tend to keep the mind engaged in sensory stimulation as the brain continually processes the auditory signals. Depending on how the products are used, they will employ controlled focus (the user strives to keep attention on listening) or open monitoring (the user listens passively without controlling attention). In either case, the approach of stimulating the brain with outer sensory input is very different from automatic self-transcending through the Transcendental Meditation technique.

International Journal of Neuroscience 14: 147–151, 1981
Rather than sustaining mental or sensory activity, the TM technique allows mental activity to subside systematically until the faintest impulse of thought is transcended and one experiences the silent state of pure consciousness, described as “unbounded” or non-localized awareness. Neurophysiological studies show that TM practice produces a distinct state of restful alertness: the body gains deep relaxation, inner wakefulness increases, and brain function becomes more integrated and efficient. High levels of alpha brain wave coherence and synchrony are displayed throughout the brain’s frontal area (and also spreading from the front to the back of the brain). This is the signature brain wave pattern of the TM technique—high amplitude alpha coherence. It is an EEG pattern not reported by research on brain entrainment products or other forms of meditation. Additional physiological changes found to commonly occur during the TM technique include marked decreases in plasma lactate, reduced respiration and higher skin resistance—all indicators of deep physiological rest.[1]

Although many users of entrainment products report benefits, a search on the U.S. Government’s health research database (PubMed) does not show that the many benefits claimed have been substantiated by scientific studies. 

In contrast (and this is another distinguishing factor of the TM program), hundreds of peer-reviewed research studies confirm the benefits of twice-daily TM practice for improving mind, body and behavior.

CLICK IMAGE TO ENLARGE
During TM practice, one experiences that it is the mind's inherent nature to settle inward and experience the state of pure awareness. While it may be possible, theoretically, to transcend during any form of meditation, binaural beat or entrainment products — which have their specific benefits — tend to keep the mind active and engaged in outer, auditory stimulation. The Transcendental Meditation technique allows the mind to spontaneously settle inward and experience finer, increasingly subtler stages of the thinking process, until one transcends thought and arrives at the source of thought—the silent state of pure awareness.
  
More about the TM technique and brain entrainment:

What is entrainment?
Measured by EEG (electroencephalograph), brain waves represent faint electrical activity of neurons in the brain. When we are mentally active, the EEG normally shows a jumble of different brain waves at various frequencies. When we’re in a relaxed, yet conscious state, certain areas of the brain may emit alpha rhythms (moderately slow brain wave frequencies of 8-12hz). When we’re drowsy, brain waves slow to the theta range (6-7hz), and in deep sleep to the even slower delta range (4-5hz). The pace of these natural rhythms is set by deep structures in the brain.

CLICK IMAGE TO ENLARGE
 “Entrainment” is a phenomenon whereby external sensory stimulation synchronizes brain waves differently than the brain’s native rhythm. For example, a strobe light can cause the frequency of one’s brain waves to match (or entrain with) the frequency of the rapidly flashing light. Combined frequencies of sound also have been found to influence or entrain brain waves.

Meditation and the brain: what science says
Although neuroscientists have known about entrainment’s temporary effect on brain waves for decades, there appears to be insufficient peer-reviewed scientific research to substantiate the claim that entrainment or “binaural beat” audio products can improve brain performance.

There is ample evidence that certain meditative states produce corresponding brain wave patterns. Since the early 1970s, scientists have been recording coherence and synchrony of brain waves in subjects practicing the Transcendental Meditation technique. Today, after 40 years of research into the effects of meditation, dozens of peer-reviewed scientific studies have verified that TM practice creates high amplitude alpha coherence.[2] This more integrated, efficient style of brain functioning is the basis of improved mental performance and self-development.

Natural versus artificial
Some brain entrainment products claim to induce a mind-body state similar to the state associated with the Transcendental Meditation technique. However, scientific research has not yet demonstrated that such products can generate EEG coherence in the alpha frequency. Nor has research confirmed the fundamental premise of entrainment products: that by externally inducing a particular brain wave pattern, the meditative state associated with that pattern can be reproduced.

One major difference between the Transcendental Meditation technique and brain entrainment products is that during TM practice, the change in brain waves is not imposed from the outside, but happens naturally from within. As the mind settles inward during the TM technique, all mental activity is transcended and one arrives at the state of pure consciousness — experienced as the deepest, most creative and blissful level of the mind. Because of the natural connection between mind and body, when the mind settles quietly inward during this process, the physiology gains deep rest; spontaneously and of its own accord the brain becomes highly coherent and synchronized.

Entrainment products are intended to drive the system into a modified style of functioning by externally manipulating one aspect of the physiology, the brain waves. This is very different from allowing the mind and body to naturally shift into the meditative state during TM practice, a process whereby the whole system spontaneously reorganizes itself into a state of greater balance and coherence. For example, research studies show that if one’s cortisol levels are too high, then during TM practice cortisol drops to more normal levels. If cortisol is too low, then it rises. The same is has been found for serotonin metabolite. Such research suggests that the deep, coherent rest gained during TM practice stimulates the system’s natural balancing mechanism. Brain researchers have said the TM technique “resets the brain’s natural ground state.” There is no evidence that this balancing of the whole system in all its complexity can take place by manipulating a single individual part such as brain waves.

When EEG measurements show brain wave changes during TM practice, this shift in brain functioning happens as a natural by-product of meditation, and is only one aspect of the many, holistic mind-body changes common to the TM technique.

REFERENCES:
1. Hormones and Behavior, 10: 1, 1978; Psychoneuroendocrinology 22:4, 1997; Journal of Alternative and Complimentary Medicine 1: 3, 1995.
2. Consciousness and Cognition, 8, 302-318, 1999; International Journal of Neuroscience 14: 147–151, 1981; Cognitive Processing, 11:1, 2010
How the TM technique compares to:
• Common “mantra” meditation 
• Zen and concentration practices 
• Guided meditation
• Contemplation/contemplative practices 
• Mindfulness 
• Relaxation response 
• Neurofeedback 
What is the “fourth state of consciousness?”