Audio-Visual Entrainment, History and Physiological Mechanisms - by Dave Siever

Copyright 2006. Reproduction of this material ismore malleable and open to new healthy thoughts,
allowed as long as it is unaltered and complete withpost-hypnotic suggestions, brainwave activity and so
Mind Alive contact information. Reproduction foron. During AVE, the EMG and electro-dermal
marketing purposes is prohibited without permissionresponses fall, finger temperature increases and
from Mind Alive Inc.breathing becomes smooth and diaphragmatic. These
Historychanges reflect a return to homeostasis or
Clinical reports of flicker stimulation appear as far backrestabilization, hence the term dissociation and
as the dawn of modern medicine. It was at the turn ofrestabilization (DAR) (40).
the 20th century when Pierre Janet, at theFigure 9 shows a typical reduction in forearm EMG
Salpêtrière Hospital in France, reported that when heand Figure 10 shows a typical increase in finger
had his patients gaze into the flickering light producedtemperature. Notice that restabilization begins after
from a spinning spoked wheel in front of a keroseneabout six minutes of AVE, when the user begins
lantern, it lowered their depression, tension and hysteriadissociating. Figure 11 shows normalization of breathing
(34). Then, in 1934, Adrian and Matthews published theirand heart rate variability following exposure to AVE at
results showing that the alpha rhythm could be "driven"7.8 Hz.
above and below the natural frequency with photicFigure 9. Forearm EMG Levels During AVE (Hawes,
stimulation (1).2000)
This discovery further propagated dozens of small*** For the complete article with figures included,
physiological outcome studies on the "flicker followingplease see... ***
response" by many well respected researchersFigure 10. Peripheral Temperature Levels During AVE
(4,5,11,20,18,22,43). However no one considered the(Hawes, 2000)
subjective and behavioral effects of photic stimulation.*** For the complete article with figures included,
Finally in 1956, W. Gray Walter published the results onplease see... ***
thousands of test subjects comparing flicker stimulationNeurotransmitters
with the subjective emotional feelings it produced (46).There is evidence that blood serum levels of serotonin,
Meanwhile, William Kroger accomplished otherendorphine, and melatonin rise considerably following 10
important developments in photic stimulation. KrogerHz., white-light AVE (42). Increases in endorphines
was a physician investigating why radar operatorsreflect increased relaxation while increased
were going into trances in front of their radar sets andnorepinephrine along with a reduction in daytime levels
of course, leaving the ship or plane at great risk to theof melatonin, indicate increased alertness (Figure 11).
enemy. He concluded that the rhythmic "blip" of theFigure 11. Neurotransmitter Levels Following AVE (42)
radar was "pulling" the radar operators into a trance*** For the complete article with figures included,
state. These findings compelled Kroger to team upplease see... ***
with Sydney Schneider of the Schneider InstrumentDendritic Growth
Company of Ohio to construct and market the firstThere is evidence that stimulating neurons with mild
electronic clinical photic stimulator, called theelectrical stimulation promotes growth of dendrites and
"Brainwave Synchronizer." It comprised of an intensedendritic shaft synapses in the cells being stimulated (6,
xenon strobe light complete with a rotating dial that25). However, studies do not yet exist on the influence
could be set to the frequencies of the standard fourof AVE on dendritic growth, although it is suspected
brain wave rhythms. They found the Brainwavebecause many people with autism, palsy, stroke and
Synchronizer had powerful hypnotic qualities and soonaneurysm (36) have gained significant motor and
published a study on hypnotic induction (24). They alsocognitive function following a treatment program of
prompted other studies involving hypnotic induction inAVE.
surgery and dentistry, and studies of general interest toCerebral Blood Flow
the hypnosis profession (38, 31, 29).Cerebral blood flow (CBF) is essential for good mental
In 1981, my wife, Nancy, and I incorporated Comptronichealth and function. SPECT and FMRI imaging of CBF
Devices Limited, with a focus on designing TENS unitsshow that hypoperfusion of CBF is associated with
and EMG feedback devices for dental (TMJ)many forms of mental disorders. CBF increases
applications. In 1984, I designed the "Digital Audio-Visualdramatically during AVE (12, 39). Figure 18 shows an
Integration Device" (DAVID1), used for hypnoticincrease of 28% in cerebral blood flow within the
induction and to calm anxiety in performing artsstriate cortex, a primary visual processing area within
students at the University of Alberta. The "light andthe occiput. As an interesting note, maximal CBF
sound" (L&S) market at this time was in its infancy andoccurs at 7.8 Hz, the Schumann Resonance of the
resided primarily within the new age sector. There wasearth.
little "known" research to support L&S technology, andFigure 12. Cerebral Blood Flow at Various AVE
professionals by and large showed disinterest. DueRepetition Rates (12)
mainly to poorly designed L&S products and a lack of*** For the complete article with figures included,
research, about 40 L&S companies have come andplease see... ***
gone, most of them during the 1980s and 1990s.Following Fox and Raichle's study was a whole head
However, since the time of Adrian and Matthews, aPET analysis of visual entrainment at 0, 1, 2, 4, 7, and14
considerable number of studies have verified photicHz (32). This study on 19 healthy, elderly (mean
and auditory "driving" of the EEG. I have sinceage=64 years) subjects found that regional cerebral
re-named this phenomenon as "audio-visualblood flow (rCBF) was activated differentially with the:
entrainment" or AVE, as any given frequency of1) left anterior cingulate showing maximal increases in
stimulation that is reflected in brain wave activity andrCBF at 4 Hz.
observable on an EEG or QEEG can be entrained.2) right anterior cingulate showing decreases in rCBF
Many more studies on photic or combined audio/photicwith frequency.
stimulation exist than pure audio stimulation studies,3) left middle temporal gyrus showing increases in
however audio-only stimulation studies have confirmedrCFB at 1 Hz.
audio entrainment (8) and its effect on calming4) striate cortex showing maximal rCBF at 7 Hz.
masseter muscle tension (30).5) lateral and inferior visual association areas showing
Physiology of Audio-Visual Entrainmentincreases in rCBF with frequency.
In order for entrainment to occur, a constant, repetitiveWhile there may be benefits to increasing occipital
stimuli of sufficient strength to "excite" the thalamusCBF, there is even greater concern regarding
must be present. The thalamus then passes the stimuliconditions involving hypoperfuson of CBF in frontal
onto the sensory-motor strip, the cortex in general andregions. Frontal disorders include: anxiety, depression,
associated processing areas such as the visual andattentional and behavior disorders, and impaired
auditory cortexes. Figure 1 shows the visual pathwaycognitive function (2). Figure 13 shows an increase in
with the retina of both eyes becoming excited andfrontal CBF recorded on Hershel Toomin's "Thinking
sending pulses down the optic nerve, through the opticCap" (or "Hemoencephalogram") using infra-red light to
chiasm, and into the lateral geniculate of both thalami.measure perfusion of CBF. Notice that CBF at FPZ
From here, the visual signals are passed onto theincreases by 15% in 10 minutes (Toomin, personal
visual and cerebral cortexes for further processing.communication).
Notice that there is very little delay from the onset ofFigure 13 Hemoencephalographic Measure of Cerebral
the flash to the response in the optic nerve, but aBlood Flow During 10 Hz AVE
delay of approximately 100 msec occurs by the time*** For the complete article with figures included,
the visual evoked potential (VEP) is elicited in the visualplease see... ***
cortex. This delay may be why entrainment occursNormalized EEG Activity
best at the natural alpha frequency -- as 100 msecFigure 14 shows a fairly typical brain map in 1 Hz bins
equates to 10 Hz.of a person with mild depression and anxiety as
Figure 1. The EEG Photic Stimulation Pathshown on the Skil database. Notice that alpha is
*** For the complete article with figures included,slowed and approaching +2SD from the norm and that
please see... ***some beta frequencies (16-18 Hz) are high (>1SD) in
Photic entrainment begins its process as a series ofcentral frontal areas.
overlapping evoked potentials (23). Kinney broke downFigure 14. Brain Map in 1 Hz Bins of Individual with
a simple VEP into its various components (Figure 2)Depression and Anxiety (SKIL-Eyes Open)
representing the passage of time for 4, 8, 12 and 20*** For the complete article with figures included,
Hz. As can be seen, much of the VEP occurs withinplease see... ***
250 msec, correlating to four Hz. The variousFollowing an AVE session of 7.8 Hz., both alpha and
overlapping parts were then vector summed into thebeta activity are normalized as shown below in Figure
mathematical VEP and compared with the actual15.
VEPs observed by EEG at the higher, entrainedFigure 15. Brain Map Following 7.8 Hz AVE (SKIL-EO)
frequencies, shown in Figure 2.*** For the complete article with figures included,
Figure 2. EEG Waveletplease see... ***
*** For the complete article with figures included,Conclusion
please see... ***In closing, AVE has the ability to quickly and effectively
When this mathematical model was compared withrelax people out of high sympathetic activation and
the actual observed EEG of the entrained stimulitraumatic states of mind, bringing a return to
(Figure 3), a high degree of predictability was observed,homeostasis. AVE may be used alongside hypnotic
demonstrating that photic entrainment is indeed asuggestions on tape/CD or live via a microphone. At
vector summation of VEPs and not a novel neuronalthe same time however, AVE exerts a powerful
process.influence on brain/mind stabilization and normalization.
Figure 3. EEG VEPs - Vector Addition (theoretical)At the end of an AVE session, the user may realize
Model vs Observed EEGthat he/she has not felt so relaxed for years --
*** For the complete article with figures included,perhaps not since childhood.
please see... ***Footnote:
By definition, entrainment occurs when an EEG reflects1. For more information, address all correspondence to:
the brain wave frequency duplicating that of the stimuli,David Siever, c/o Mind Alive Inc., 9008 - 51 Avenue,
be it audio, visual or tactile (41). Entrainment occursEdmonton, Alberta, Canada, T6E 5X4
best near one's own natural alpha frequency (43, 23).Toll Free: (800) 661-6463 Fax: (780) 461-9551 Web:
LEDs and xenon strobe lights contain much harmonicEmail: References
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Entrainment primarily shows itself frontally and near theResponse to clicks from the human brain: Some depth
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entrainment.electronic aid for hypnotic induction: A preliminary
Figure 6. Photic Stimulation Induction of Hypnoticreport. International Journal of Clinical and Experimental
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*** For the complete article with figures included,25) Lee, K., Schottler, F., Oliver, M., & Lynch, G. (1980).
please see... ***Brief bursts of high-frequency stimulation produce two
Psychologists have been looking for ways totypes of structural change in rat hippocampus. Journal
dissociate their clients as a part of fear and phobiaof Neurophysiology, 44 (2), 247-258.
treatment. Inducing dissociation using AVE delivered by26) Leonard, K., Telch, M., & Harrington, P. (1999).
the DAVID1 was found to be more effective than dotDissociation in the laboratory: A comparison of
staring or stimulus deprivation (26) as shown in Figurestrategies. Behaviour Research and Therapy, 37, 49-61.
7.27) Leonard, K., Telch, M., & Harrington, P. (2000). Fear
Figure 7. AVE Induced Dissociation (26)response to dissociation challenge. Anxiety, Stress and
*** For the complete article with figures included,Coping, 13, 355-369.
please see... ***28) Lipowsky, Z. (1975). Sensory and information inputs
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Inventory (ADI) is a 35-item self-report scale (26). Itbiofeedback to bruxism and myofascial
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was that their heart rate actually decreased, contrarypattern-flash visual stimulus during PET differentially
to normal anxiety reactions (Figure 8). With the abilityactivates brain from striate through frontal cortex.
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*** For the complete article with figures included,Pierre Janet. Acta Psychiatrica Belgica, 1, 7-112).
please see... ***35) Regan, D. (1966). Some characteristics of average
A dissociative mindstate or hypnotic trance may besteady-state and transient responses evoked by
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consciousness (ASC) in which the subject (or anNeurophysiology, 20, 238-248.
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qualitative shift in the normal pattern of mentalmultimodal rehabilitation of a 43-year-old severely
functioning (16). ASCs produced via overstimulationimpaired postaneurysm patient. Biofeedback and Self
also occur when a person is bombarded with higherRegulation, 21, 4.
than normal levels of sensory input, usually in more37) Ruuskanen-Uoti, H. & Salmi, T. (1994, January).
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conducive to an ASC.entrainment technology. Unpublished manuscript.
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necessary nor all that is involved to indicate thelearning. Unpublished manuscript.
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Glicksohn's observations support the concept that inneurotransmitters produced by brainwave entrainment.
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must have a direct impact on brain wave frequencyA study done for Comprehensive Health Care,
and be observable on an EEG.Unpublished.
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