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Binaural beats are auditory brainstem
responses which originate in the superior olivary nucleus of
each hemisphere. They result from the interaction of two
different auditory impulses, originating in opposite ears,
below 1000 Hz and which differ in frequency between one and 30
Hz (Oster, 1973).For example, if a pure tone of 400 Hz is
presented to the right ear and a pure tone of 410 Hz is
presented simultaneously to the left ear, an amplitude
modulated standing wave of 10 Hz, the difference between the
two tones, is experienced as the two wave forms mesh in and
out of phase within the superior olivary nuclei. This binaural
beat is not heard in the ordinary sense of the word (the human
range of hearing is from 20-20,000 Hz). It is perceived as an
auditory beat and theoretically can be used to entrain
specific neural rhythms through the frequency-following
response (FFR)--the tendency for cortical potentials to
entrain to or resonate at the frequency of an external
stimulus. Thus, it is theoretically possible to utilize a
specific binaural-beat frequency as a consciousness management
technique to entrain a specific cortical rhythm.
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The binaural-beat appears to be associated
with an electroencephalographic (EEG) frequency-following
response in the brain(3). Many studies have demonstrated the
presence of a frequency-following response to auditory
stimuli, recorded at the vertex of the human brain (top of the
head). This EEG activity was termed "frequency-following
response" because its period corresponds to the fundamental
frequency of the stimulus (Smith, Marsh, & Brown, 1975).
Binaural-beat stimulation appears to encourage access to
altered states of consciousness.
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Uses of audio with embedded binaural beats
that are mixed with music or various pink or background sound
are diverse. They range from relaxation, meditation, stress
reduction, pain management, improved sleep quality, decrease
in sleep requirements, super learning, enhanced creativity and
intuition, remote viewing, telepathy, and out-of-body
experience and lucid dreaming. Audio embedded with binaural
beats is often combined with various meditation techniques, as
well as positive affirmations and visualization.
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Resonant entrainment of oscillating
systems is a well-understood principle within the physical
sciences. If a tuning fork designed to produce a frequency of
440 Hz is struck (causing it to oscillate) and then brought
into the vicinity of another 440 Hz tuning fork, the second
tuning fork will begin to oscillate. The first tuning fork is
said to have entrained the second or caused it to resonate.
The physics of entrainment apply to biosystems as well. Of
interest here are the electromagnetic brain waves. The
electrochemical activity of the brain results in the
production of electromagnetic wave forms which can be
objectively measured with sensitive equipment. Brain waves
change frequencies based on neural activity within the brain.
Because neural activity is electrochemical, brain function can
be modified through the introduction of specific chemicals
(drugs), by altering the brain’s electromagnetic environment
through induction, or through resonant entrainment
techniques.
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Binaural beats were discovered in 1839 by
a German experimenter, H. W. Dove. The human ability to "hear"
binaural beats appears to be the result of evolutionary
adaptation. Many evolved species can detect binaural beats
because of their brain structure. The frequencies at which
binaural beats can be detected change depending upon the size
of the species’ cranium. In the human, binaural beats can be
detected when carrier waves are below approximately 1000 Hz
(Oster, 1973). Below 1000 Hz the wave length of the signal is
longer than the diameter of the human skull. Thus, signals
below 1000 Hz curve around the skull by diffraction. The same
effect can be observed with radio wave propagation.
Lower-frequency (longer wave length) radio waves (such as AM
radio) travel around the earth over and in between mountains
and structures. Higher-frequency (shorter wave length) radio
waves (such as FM radio, TV, and microwaves) travel in a
straight line and can’t curve around the earth. Mountains and
structures block these high-frequency signals. Because
frequencies below 1000 Hz curve around the skull, incoming
signals below 1000 Hz are heard by both ears. But due to the
distance between the ears, the brain "hears" the inputs from
the ears as out of phase with each other. As the sound wave
passes around the skull, each ear gets a different portion of
the wave. It is this waveform phase difference that allows for
accurate location of sounds below 1000 Hz(9). Audio direction
finding at higher frequencies is less accurate than it is for
frequencies below 1000 Hz. At 8000 Hz the pinna (external ear)
becomes effective as an aid to localization. In summary it’s
the ability of the brain to detect a waveform phase difference
is what enables it to perceive binaural beats.
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How It Works On The Brain
When signals of two different frequencies
are presented, one to each ear, the brain detects phase
differences between these signals. "Under natural
circumstances a detected phase difference would provide
directional information. The brain processes this anomalous
information differently when these phase differences are heard
with stereo headphones or speakers. A perceptual integration
of the two signals takes place, producing the sensation of a
third "beat" frequency. The difference between the signals
waxes and wanes as the two different input frequencies mesh in
and out of phase. As a result of these constantly increasing
and decreasing differences, an amplitude-modulated standing
wave -the binaural beat- is heard. The binaural beat is
perceived as a fluctuating rhythm at the frequency of the
difference between the two auditory inputs. Evidence suggests
that the binaural beats are generated in the brainstem’s
superior olivary nucleus, the first site of contralateral
integration in the auditory system (Oster, 1973). Studies also
suggest that the frequency-following response originates from
the inferior colliculus (Smith, Marsh, & Brown, 1975)"
(Owens & Atwater, 1995). This activity is conducted to the
cortex where it can be recorded by scalp
electrodes.
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Binaural beats can easily be heard at the
low frequencies (< 30 Hz) that are characteristic of the
EEG spectrum (Oster, 1973). This perceptual phenomenon of
binaural beating and the objective measurement of the
frequency-following response (Hink, Kodera, Yamada, Kaga,
& Suzuki, 1980) suggest conditions which facilitate
entrainment of brain waves and altered states of
consciousness. There have been numerous anecdotal reports and
a growing number of research efforts reporting changes in
consciousness associated with binaural-beats. "The subjective
effect of listening to binaural beats may be relaxing or
stimulating, depending on the frequency of the binaural-beat
stimulation" (Owens & Atwater, 1995). Binaural beats in
the delta (1 to 4 Hz) and theta (4 to 8 Hz) ranges have been
associated with reports of relaxed, meditative, and creative
states (Hiew, 1995), and used as an aid to falling asleep.
Binaural beats in the alpha frequencies (8 to 12 Hz) have
increased alpha brain waves (Foster, 1990) and binaural beats
in the beta frequencies (typically 16 to 24 Hz) have been
associated with reports of increased concentration or
alertness (Monroe, 1985) and improved memory (Kennerly,
1994).
Passively listening to binaural beats may
not spontaneously propel you into an altered state of
consciousness. One’s subjective experience in response to
binaural-beat stimulation may also be influenced by a number
of mediating factors. For example, the willingness and ability
of the listener to relax and focus attention may contribute to
binaural-beat effectiveness in inducing state changes.
"Ultradian rhythms in the nervous system are characterized by
periodic changes in arousal and states of consciousness
(Rossi, 1986;
Shannahoff-Khalsa, 1991; Webb & Dube,
1981). These naturally occurring shifts may underlie the
anecdotal reports of fluctuations in the effectiveness of
binaural beats. External factors are also thought to play
roles in mediating the effects of binaural beats" (Owens &
Atwater, 1995). The perception of a binaural beat is, for
example, said to be heightened by the addition of white noise
to the carrier signal (Oster, 1973), so white noise is often
used as background. "Music, relaxation exercises, guided
imagery, and verbal suggestion have all been used to enhance
the state-changing effects of the binaural beat" (Owens &
Atwater, 1995). Other practices such as humming, toning,
breathing exercises, autogenic training, and/or biofeedback
can also be used to interrupt the homeostasis of resistant
subjects (Tart, 1975).
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Controversies concerning the brain, mind,
and consciousness have existed since the early Greek
philosophers argued about the nature of the mind-body
relationship, and none of these disputes has been resolved.
Modern neurologists have located the mind in the brain and
have said that consciousness is the result of electrochemical
neurological activity. There are, however, growing
observations to the contrary. There is no neurophysiological
research which conclusively shows that the higher levels of
mind (intuition, insight, creativity, imagination,
understanding, thought, reasoning, intent, decision, knowing,
will, spirit, or soul) are located in brain tissue (Hunt,
1995). A resolution to the controversies surrounding the
higher mind and consciousness and the mind-body problem in
general may need to involve an epistemological shift to
include extra-rational ways of knowing (de Quincey, 1994) and
cannot be comprehended by neurochemical brain studies alone.
We are in the midst of a revolution focusing on the study of
consciousness (Owens, 1995). Penfield, an eminent contemporary
neurophysiologist, found that the human mind continued to work
in spite of the brain’s reduced activity under anesthesia.
Brain waves were nearly absent while the mind was just as
active as in the waking state. The only difference was in the
content of the conscious experience. Following Penfield’s
work, other researchers have reported awareness in comatose
patients (Hunt, 1995) and there is a growing body of evidence
which suggests that reduced cortical arousal while maintaining
conscious awareness is possible (Fischer, 1971;West 1980;
Delmonte, 1984; Goleman 1988; Jevning, Wallace, &
Beidenbach, 1992; Wallace, 1986; Mavromatis, 1991). These
states are variously referred to as meditative, trance,
altered, hypnogogic, hypnotic, and twilight-learning states
(Budzynski, 1986). Broadly defined, the various forms of
altered states rest on the maintenance of conscious awareness
in a physiologically reduced state of arousal marked by
parasympathetic dominance (Mavromatis, 1991). Recent
physiological studies of highly hypnotizable subjects and
adept meditators indicate that maintaining awareness with
reduced cortical arousal is indeed possible in selected
individuals as a natural ability or as an acquired skill
(Sabourin, Cutcomb, Crawford, & Pribram, 1993). More and
more scientists are expressing doubts about the neurologists’
brain-mind model because it fails to answer so many questions
about our ordinary experiences, as well as evading our
mystical and spiritual ones. The scientific evidence
supporting the phenomenon of remote viewing alone is
sufficient to show that mind-consciousness is not a local
phenomenon (McMoneagle, 1993).
If mind-consciousness is not the brain,
why then does science relate states of consciousness and
mental functioning to brain-wave frequencies? And how is it
that audio with embedded binaural beats alters brain waves?
The first question can be answered in terms of
instrumentation. There is no objective way to measure mind or
consciousness with an instrument. Mind-consciousness appears
to be a field phenomenon which interfaces with the body and
the neurological structures of the brain (Hunt, 1995). One
cannot measure this field directly with current
instrumentation. On the other hand, the electrical potentials
of brain waves can be measured and easily quantified.
Contemporary science likes things that can be measured and
quantified. The problem here lies in oversimplification of the
observations. EEG patterns measured on the cortex are the
result of electroneurological activity of the brain. But the
brain’s electroneurological activity is not
mind-consciousness. EEG measurements then are only an indirect
means of assessing the mind-consciousness interface with the
neurological structures of the brain. As crude as this may
seem, the EEG has been a reliable way for researchers to
estimate states of consciousness based on the relative
proportions of EEG frequencies. Stated another way, certain
EEG patterns have been historically associated with specific
states of consciousness. It is reasonable to assume, given the
current EEG literature, that if a specific EEG pattern emerges
it is probably accompanied by a particular state of
consciousness.
As to the second question raised in the
above paragraph, audio with embedded binaural beats alters the
electrochemical environment of the brain. This allows
mind-consciousness to have different experiences. When the
brain is entrained to lower frequencies and awareness is
maintained, a unique state of consciousness emerges. This
state is often referred to as hypnogogia "mind awake/body
asleep." Slightly higher-frequency entrainment can lead to
hyper suggestive states of consciousness. Still
higher-frequency EEG states are associated with alert and
focused mental activity needed for the optimal performance of
many tasks. Perceived reality changes depending on the state
of consciousness of the perceiver (Tart, 1975). Some states of
consciousness provide limited views of reality, while others
provide an expanded awareness of reality. For the most part,
states of consciousness change in response to the
ever-changing internal environment and surrounding
stimulation. For example, states of consciousness are subject
to influences like drugs and circadian and ultradian rhythms
(Rossi, 1986; Shannahoff-Khalsa, 1991; Webb & Dube, 1981).
Specific states of consciousness can also be learned as
adaptive behaviors to demanding circumstances (Green and
Green, 1986).
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Synchronized brain waves have long been
associated with meditative and hypnogogic states, and audio
with embedded binaural beats has the ability to induce and
improve such states of consciousness. The reason for this is
physiological. Each ear is "hardwired" (so to speak) to both
hemispheres of the brain (Rosenzweig, 1961). Each hemisphere
has its own olivary nucleus (sound-processing center) which
receives signals from each ear. In keeping with this
physiological structure, when a binaural beat is perceived
there are actually two standing waves of equal amplitude and
frequency present, one in each hemisphere. So, there are two
separate standing waves entraining portions of each hemisphere
to the same frequency. The binaural beats appear to contribute
to the hemispheric synchronization evidenced in meditative and
hypnogogic states of consciousness. Brain function is also
enhanced through the increase of cross-collosal communication
between the left and right hemispheres of the
brain.
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Your brain cells reset their sodium &
potassium ratios when the brain is in Theta state. The sodium
& potassium levels are involved in osmosis which is the
chemical process that transports chemicals into and out of
your brain cells. After an extended period in the Beta state
the ratio between potassium and sodium is out of balance. This
the main cause of what is known as "mental fatigue". A brief
period in Theta (about 5 - 15min) can restore the ratio to
normal resulting in mental refreshment.
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