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According to physics our hearing sense can function completely different'

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Title: According to physics our hearing sense can function completely different'


1
According to physicsour hearing sense can
functioncompletely different.
Slechthorend - plus.nl
  • Willem Chr. Heerens

2
May I introduce myself
Slechthorend - plus.nl
  • Willem Chr. Heerens 1940
  • Masters degree in physics
    1967
  • Doctors degree in technical sciences
    1979
  • Earlier retirement as associate professor
    TU-Delft 1999
  • Papers about hearing www.slechthorend-plus.nl
    2003

3
Relevant for my contributions in hearing issues
Slechthorend - plus.nl
Technical expertise particularly in
  • Mechanics Membrane plate displacements.
  • Vacuum technology pressure measurement.
  • Physics transport phenomena hydrodynamics.
  • Electricity magnetism.
  • Sensor technology electrical measurement
    techniques.
  • Fourier analysis special function theory.
  • Differential integral mathematics.
  • Complex function theory.

4
Slechthorend - plus.nl
Hearing expertise
  • Since 1985 as Ménière patient Expert in
    the field.
  • During quite a couple of years direct
    observations of several hearing phenomena and
    effects.
  • Since 2001 Autodidact and theoretic hearing
    researcher.
  • Meanwhile designer of a revolutionary and
    alternative
  • COCHLEAR MODEL

Based on stringent application of laws and rules
of physics.
  • What perhaps can lead to a
  • paradigm shift

5
Therefore the intriguing title
Slechthorend - plus.nl
According to physicsour hearing sense can
functioncompletely different.
6
Points of criticism on the existing models
Slechthorend - plus.nl
  • Mostly they offer only solutions for parts of the
    total subject.
  • Too many phenomena remain unexplained.
  • Mostly unexplained phenomena are ascribed to
    functioning of the brain without clear evidence.
  • New refined investigations offer a growing number
    of anomalies that undermine the existing hearing
    sense models.
  • Respectable research quite often fails plausible
    logic explanation.
  • But above all
  • Several hypotheses declared as basic theory are
    in conflict with fundamental physics laws and
    rules.

7
Ernest Glen Wever and Merle Lawrence  The
acoustic pathways to the cochlea  JASA
1950 July, 22 460-467
Slechthorend - plus.nl
One such a respectable research effort
  • Experiment
  • In a cats ear they eliminated eardrum
    ossicular chain.
  • They fabricated a tube around the round window to
    isolate it acoustically from the oval window
    area.
  • They stimulated with pure tones as follows
  • Stimulus only on the oval window.
  • Stimulus only on the round window.
  • Stimulus on both windows with different phases,
    varying in phase between 0o and 180o
  • They recorded the cochlear microphonics, the
    signal that is widely and directly brought into
    connection with the signal via the auditory nerve.

8
Results
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  • Independent stimulation of each window with the
    same signal resulted in equal changes in
    cochlear microphonics CM.
  • Combined stimulation of both windows in the same
    direction 0o resulted in
  • CM 0
  • Stimulation of both windows in opposite
    directions 180o phase shift resulted in
  • CM maximal
  • That maximum was 6 dB higher than each of the
    two stimuli alone performed.
  • In-between phase settings evoked vectorial
    increase of CM from 0 to a maximum at phase
    differences of the stimuli from 0o to 180o.

9
Quite recently verified by
Slechthorend - plus.nl
S.E. Voss, J.J. Rosowski, W.T Peake Is the
pressure difference between the oval and round
windows the stimulus for cochlear responses?
JASA(1996) Sep.,100(3) 1602-16.
  • which resulted in
  • Affirmation of the results of Wever Lawrence.
  • In this experiment from the cochlear potential
    CP signal both the Differential mode D
    differential component in the signal
  • and the Common mode C alternating
    component show
  • equal behavior.
  • C is measured as ca. 35 dB lower than D.

10
Conclusions
Slechthorend - plus.nl
  • E.G. Wever M. Lawrence
  • It is proven that the stimulation of the same
    sensory cells takes place via each of the two
    ways with the same intensity pattern.
  • Over almost the total frequency range a minimum
    in response is obtained if both waves stimulate
    in phase the oval respectively the round window.
  • Distortions of this relation, most significant
    for higher frequencies, are apparently due to
    differences in reactions of the two windows.

S.E. Voss, J.J. Rosowski, W.T Peake
  • The pressure differences between the oval and
    round window are in good approximation the
    effective acoustic stimulus for the cochlea.

11
My conclusions based on mathematics physics'
laws and rules
Slechthorend - plus.nl
  • An electrical response CM or CP is only evoked
    in case of an evoked perilymph movement in the
    combined ducts of scala vestibuli SV and scala
    tympani ST.
  • In case of maximal cooperation between the two in
    size equal stimuli 180o phase shift the total
    movement stimulus is two times larger.
  • But then the changes in electrical response are
    not becoming two but four times as large.
  • Just because 10 10log 4 6 dB
  • The electrical response in the inner ear is
    proportional to the
  • square of the de perilymph velocity.

12
differentiating and squaring
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Our hearing sense is
  • But then the question rises

Does there exist in physics such a relationship?
And the answer is yes already known for a
long time
Bernoullis law
published in 1738.
13
And that law of Bernoulli is formulated as
Slechthorend - plus.nl
  • In a floating liquid the sum of the static and
    dynamic pressure is constant.

Static pressure pressure on the walls of
the duct. Dynamic pressure pressure that
the particles are evoking on each other
due to their floating. Dynamic
pressure is proportional to the square of the
liquid velocity v and the density r of the
liquid.
14
Bernoullis law expressed in a formula
Slechthorend - plus.nl
  • and applied on the cochlear duct
  • Pressure evoked on the wall of scala tympani, so
    also on the basilar membrane
  • Dp - ½ r v2
  • Dp change in pressure Pa
  • r density perilymph kg/m3
  • v velocity perilymph m/s

15
To what result leads this for a single tone with
frequency f ?
Slechthorend - plus.nl
  • The sound wave evokes in front of the eardrum
    subsequent increases and decreases of pressure
  • DP DP0 sin2pf t
  • The deflection of the eardrum is proportional to
    that
  • U U0 sin2pf t
  • Via a reduction by the ossicular chain this
    also counts for the stirrup and the perilymph
    movement
  • A A0 sin2pf t

16
Slechthorend - plus.nl
  • Deflection or displacement of the perilymph
  • A A0 sin2pf t
  • Results into a velocity
  • v A0 2pf cos2pf t

Velocity time derivative of deflection or
displacement.
17
Slechthorend - plus.nl
  • Perilymph velocity
  • v A0 2pf cos2pf t
  • inserted in Bernoullis law
  • Dp - ½ rv2 - ½ rA02 4p2f 2cos22pf t
  • and with the use of the goniometric function
  • cos2x ½ ½ cos 2x
  • and simplification by
  • Dp0 ½ rA02 4p2f 2
  • Results in the stimulus of the basilar membrane,
    and can be given as
  • Dp - ½ Dp0 - ½ Dp0 cos4pf t

18
Presented in a figure
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19
Slechthorend - plus.nl
  • That pressure stimulus on the basilar membrane
    given by
  • Dp - ½ Dp0 - ½ Dp0 cos4pf t

exists of Not hearable static pressure
stimulus - ½ Dp0 Proportional to the average
sound intensity. Hearable dynamic pressure
stimulus - ½ Dp0 cos4pf t Proportional to
the instantaneous sound intensity.
20
And what happens in case of two tones with
frequencies f1 and f2 ?
Slechthorend - plus.nl
  • Sound wave evokes in front of the eardrum time
    dependent pressure increase and decrease
    according to
  • DP DP1 sin2pf1t DP2 sin2pf2t
  • And all the following mathematical steps are
    almost similar to those of one frequency, until
    the perilymph velocity
  • v v1 cos2pf1t v2 cos2pf2t
  • But then the squaring of the perilymph velocity
    must be carried out according to the following
    algebraic rule
  • (a b)2 a2 2ab b2

21
This results in the following contributions to
the pressure stimulus on the basilar membrane
Slechthorend - plus.nl
  • Contribution of the a2 term
  • Dp1 - ½ Dp01 - ½ Dp01 cos4pf1t
  • Contribution of the b2 term
  • Dp2 - ½ Dp02 - ½ Dp02 cos4pf2t
  • Contribution of the mixed term 2ab
  • Dpm - Dp0m cos2pf1t cos2pf2t
  • Dp0m rA01A02 4p2f1f2

22
That mixed term can be handled as follows
Slechthorend - plus.nl
  • Using goniometric rules for multiplied sinus and
    cosine functions
  • 2 cos a cos b cos (a - b) cos (a b)
  • finally for the contributions to the stimuli on
    the basilar membrane can be written
  • The difference frequency contribution
  • - ½ Dp0m cos2p(f1 - f2) t
  • The sum frequency contribution
  • - ½ Dp0m cos2p (f1 f2) t

23
The result?
Slechthorend - plus.nl
  • Each two evoked pure tones f1 and f2 together
    result in five distinguishable signals on the
    basilar membrane, given as
  • A frequency independent contribution proportional
    to the average sound intensity.
  • For each tone a one octave higher than the
    offered frequency signal
  • 2f1 respectively 2f2
  • A sum frequency f1 f2
  • A difference frequency f1 - f2 pitch or
    basal tone.

24
In the form of a figure
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25
But now you must realize the following
Slechthorend - plus.nl
  • At least according to physics not in our brain
    but in our hearing sense the missing fundamental
    or pitch is generated.
  • And for the total nerve signal counts
  • 1 tone ? 1 frequency 1
    static signal
  • 2 tones ? 4 frequencies 1
    static signal
  • 100 tones ? 10.000 frequencies 1
    static signal
  • Which is a real ENIGMATIC CODE.

26
The consequences
Slechthorend - plus.nl
  • Georg Von Békésys mystery of the missing
    pitch
  • is no mystery anymore.
  • Therefore violin virtuoso Tartini could let his
    soprano violin sound as a cello.
  • On smaller church organs the 32 feet pipe is
    missing. But if the organist let sound in the
    proper amplitude ratio simultaneously the 16
    feet and 10 2/3 feet pipes, his audience will
    nevertheless hear that very low bass tone of that
    huge pipe.
  • But their stomach does not vibrate as well. That
    only happens when that bass pipe really sounds.
  • The theoretical textbooks about virtual pitch
    in sound perception can be added to the historic
    archive.

27
But there is more
Slechthorend - plus.nl
  • Is a very young child be gifted with musical
    talent?
  • All those extra frequencies are unbearable to
    hear in a squaring hearing sense. Just
    construction not musicality.

28
What to think about the Cochlear Amplifier
Slechthorend - plus.nl
  • The stressing of the tensor tympani gives a
    change in signal transfer of about 30 times.
  • The musculus stapedius also counts for a factor
    of approximately 30 times, maybe somewhat more.
  • Together an effect of 1.000 times on the stimulus
    of the oval window.
  • Due to the squaring this becomes 1.000.000 or
    60 dB.
  • And the commanding signal for that?
  • The static pressure signal on the basilar
    membrane can serve as such.

29
Consequences of that hypothesis?
Slechthorend - plus.nl
  • A static under pressure effect on the basilar
    membrane by any cause in the hearing sense
    result in hearing loss symptoms. Accompanied by
    pressure sensations in the ear.
  • The unpleasant hearing sensations during takeoff
    or landing of an airplane.
  • Increasing, sometimes temporarily, hearing
    impairment in case of increasing endolymfatic
    hydrops in Ménière patients.
  • Sudden deafness, which sometimes can heal also
    spontaneously.
  • Hearing impairment for airborne sound in case of
    the PET syndrome by pressure fluctuations in the
    middle ear cavity on the rhythm of the own
    breathing.

30
And the other extremes?
Slechthorend - plus.nl
  • Due to degeneration of large areas in the organ
    of Corti, also resulting in reduced transfer of
    the static pressure signal, a loss of dynamic
    range, known as
  • Recruitment
  • By a trauma or other phenomenon caused reduction
    or even total loss of functioning of the tensor
    tympani and/or musculus stapedius An
    extraordinary loud hearing of the somewhat louder
    sounds. A form of
  • Hyperacusis
  • But for this last phenomenon there are more
    causes to give.

31
How does the phenomenon OAE fits in this model?
Slechthorend - plus.nl
  • Thesis
  • If a Spontaneous Oto Acoustic Emission SOAE is
    a reaction on earlier heard signals and is
    generated by tensor tympani / musculus stapedius,
    than that SOAE must have clearly traces of tone
    combinations evoked by the squaring process in
    the inner ear.
  • That tone combinations must exist of
  • Two frequencies with in the middle of them a
    third frequency. The so-called triplet
  • A singular frequency equal to the frequency
    differences in the triplet. The pitch
    belonging to the triplet.

32
Analysis of such an arbitrary SOAE spectrum
Slechthorend - plus.nl
  • From the Nederlands Tijdschrift voor Natuurkunde
    September 2001
  • Emile de Kleine Ear sounds on a wall-bed
    Title translated

33
Determined spectrum
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VW very weak W weak M moderate S strong
34
Results
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  • 3 triplets with accompanying pitch.
  • 6 triplets without a pitch.
  • But pitch frequency was lower than the lower
    boundary of 800 Hz.
  • Example triplet pitch
  • Pitch Peak 6 f 1172 Hz
  • Triplet Peaks 13 - 23 - 31 f 1674 - 2830
    - 3987 Hz.
  • Triplet distances 1156 respectively
    1157 Hz.
  • Accuracy generally within 1 of the pitch
    distance.
  • This cannot be an accident anymore !

35
The valid hypothesis for OAEs at this moment ?
Slechthorend - plus.nl
  • That sounds completely different
  • Those tones are evoked by a simultaneous effort
    of the outer hair cells, that evoke a backwards
    traveling wave in the cochlea into the direction
    of the oval window, and that finally via the
    ossicular chain brings the eardrum in motion.
  • Which is in agreement with the common hypothesis
    of traveling waves in the cochlea.
  • According to Georg von Békésys
  • Traveling wave theory

36
But in 2004 the following paper was presented
Slechthorend - plus.nl
  • Tianying Ren Reverse propagation of sound in
    the gerbil cochlea
  • Nature Neuroscience 7, pp 333 - 334 (2004) Brief
    Communications
  • Subject of many discussions Pro and Contra.
  • Experiment
  • Laser interferometrical measurement of basilar
    membrane movements.
  • Simultaneous registration of stirrup movements.
  • With stimuli, normally evoking DPOAEs
    Distorsion Product OAEs.
  • Measurement results
  • There aren't found backwards traveling waves.
  • Only a wavy movement, which equal to the normally
    incoming sound runs from the round window into
    the direction of the helicotrema.
  • The stirrup moves a fraction earlier than the
    basilar membrane.

37
Rens unintentional attacks on Von Békésys
Traveling Wave Theory
Slechthorend - plus.nl
  • An earlier paper of Ren was also a hot item
  • Longitudinal pattern of basilar membrane
    vibration in the sensitive cochlea
  • Proceedings of the National Academy of Sciences
    - pnas.org PNAS December 24, 2002 vol. 99
    no. 26 17101-17106.
  • Experiment
  • Laser interferometrical measurements of the
    basilar membrane movement.
  • In the 13,3 19 kHz area of the basilar membrane
    of a gerbil.
  • Results
  • The movement of the basilar membrane, from the
    higher frequency side towards the lower side, is
    restricted to 300 mm on both sides of the point
    of maximum activity.
  • The shape of the movement was exactly symmetrical
    around this point.

38
How do we have to interpret that wavy movement
of the basilar membrane ?
Slechthorend - plus.nl
  • In this we have to observe the following facts
    in physics
  • In a medium gas, liquid , solid material there
    exists a uniform relation between the propagation
    velocity v of sound or vibration, the frequency
    f and the wavelength l of the sound or
    vibration wave
  • v f l
  • v is lowest in gasses In air 330 m/s
  • v in water but also in perilymph 1500 m/s
  • v is highest in solid material to ca. 8000 m/s
  • Together with the lowest 20 Hz and highest
    20.000 Hz sound frequencies that we are able to
    hear, the wavelength varies in the perilymph from
    75 meter to 7,5 cm.
  • Always significantly larger than the size of the
    cochlea.

39
Consequences
Slechthorend - plus.nl
  • In the much shorter perilymph duct there cannot
    run a sound wave.
  • The perilymph between oval and round windows is
    just able to move forwards and backwards as a
    whole.
  • Tissue around the perilymph channel behaves more
    like a solid material than like a liquid.
  • That tissue needs a larger size for a traveling
    wave.
  • Conclusion
  • There cannot run a traveling wave inside the
    cochlea.

40
But what kind of movement is observed then ?
Slechthorend - plus.nl
  • Therefore we must observe at first the way of
    movement of a singular resonator.
  • A resonator exist of a body connected to a
    spring, and is possessing in practice also
    damping.
  • If the body is given a deflection in opposite
    direction to the spring influence and that body
    is released, it will move harmonically with
    descending amplitude around the equilibrium
    point. The frequency in that case is known as
    resonance frequency fr
  • If the resonator is brought into a vibrating
    movement, then three different situations can
    exist, dependent on the relationship between
    stimulus frequency f and resonance frequency
    fr
  • with phase angle
  • f lt fr reduced in phase movement
    0
  • f fr increase due to resonance but also
    a phase retardation ½ p
  • f gt fr strongly reduced movement in
    opposite direction p

41
Followed by the remarkable mechanical setup of
the basilar membrane
Slechthorend - plus.nl
  • This basilar membrane BM exists of an array of
    small resonators, that have gradually decreasing
    resonance frequencies from the round window up to
    the helicotrema.
  • And then in case of an everywhere equal in phase
    stimulus on the entire BM, the following is
    happening
  • All parts of the BM having fr gt f move in phase
    with the stimulus.
  • That movement becomes larger if fr approaches f
    closer and will retard gradually in phase. In
    case of resonance a large movement is and there
    exist a phase retardation of ½ p.
  • All parts of the BM with fr lt f are more and
    more moving in opposite phase with the stimulus
    and with a growing decreasing in deflection.

42
And what phenomenon is comparable to this?
Slechthorend - plus.nl
  • The wave in the stadium!
  • And dependent on the quality factor in
    resonance, strongly coupled to the rate of
    damping, the moving area becomes smaller, while
    the maximum deflection becomes larger.
  • On theoretical grounds it is no mystery that this
    wavy movement of the BM is always running from
    the round window base towards the helicotrema
    apex of the cochlea.
  • It is a locally bound reaction behavior on a
    universally existing stimulus.
  • Using the material specifications this behavior
    can be calculated in a perfect way.

43
And if you calculate this you will see that
movements in a graph as follows
Slechthorend - plus.nl
10
0,1
f /fr
  • Subsequent stadia in the basilar membrane
    movement cycles as response on a sinus shaped
    stimulus
  • 0 max 0 min 0 . . . .

44
And in steps of 1/24 vibration period
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45
Animation of basilar membrane movement
Slechthorend - plus.nl
  • Round window
    Helicotrema ?
  • Basilar
  • membrane
  • f / fr 0,1 Resonance
    point f fr
    f / fr 10
  • High frequencies low frequencies ?


46
But then the cochlear model still wasnt complete.
Slechthorend - plus.nl
  • The fenomenon Bone conduction was still missing
  • Based on my own experiences I observed that
  • Bone conduction in principle does not differ that
    much from airborne hearing signals. So that
    stimulus should also undergo squaring.
  • The bone conduction signal is in my case
    extremely strong if it is evoking vibrations on
    places on the skull where the skull bones are
    relatively thin.
  • The construction of the cochlea inside the
    hardest bone in our body makes vibration transfer
    by means of deformation almost completely
    impossible.

47
And after a further study of the anatomy I found
Slechthorend - plus.nl
  • Next to the by me already known endolymphatic
    channel, between the cerebrospinal cavity and the
    cochlea there exists another direct connecting
    channel, the cochlear aqueduct.
  • The cochlear aqueduct connection is relatively
    close situated in the vicinity of the round
    window in the scala tympani and exchanges
    perilymph between cerebrospinal cavity and the
    cochlea.

48
And that brought me to the following hypothesis
Slechthorend - plus.nl
  • Contrarily to what is generally assumed, bone
    conduction signals arent generated by vibrations
    of the petrosal bone, the bone structure that
    surrounds the cochlea.
  • The bone conduction signal will be evoked by
    the push pull of perilymph via the cochlear
    aqueduct. And this happens on the rhythm of the
    vibration stimulus which is evoked elsewhere.
  • In that case every area forming a part of the
    surroundings of the cerebrospinal volume with a
    greater elasticity and flexibility can be a
    candidate for the introduction of the bone
    conduction stimuli.

49
Consequences of this hypothesis are
Slechthorend - plus.nl
  • Similar as airborne sound stimuli, bone
    conduction stimuli evoke movements of perilymph
    in the perilymph duct.
  • Due to the place where they are inserted in the
    cochlear duct, the movements evoked by bone
    conduction stimuli have opposite directions to
    those of the airborne stimuli.
  • The push pull movement via the cochlear aqueduct
    is divided between flow directly towards the
    round window and flow along the basilar membrane
    via helicotrema towards the oval window.
  • But due to the squaring effect according to
    Bernoullis law the bone conduction stimuli are
    transferred into the sound intensity signal, that
    will be sent to the brain.

50
What does this mean for the ENT- practice ?
Slechthorend - plus.nl
  • In case of an otitis media the middle ear cavity
    will be filled by fluid and due to its
    incompressibility this fluid will hinder the
    deflection possibilities of the round window.
  • Putting a tune fork on the forehead, the push
    pull evoked by this bone conduction stimulus will
    follow the route of least resistance. And that
    will be along the basilar membrane via
    helicotrema, oval window, the ossicular chain and
    the eardrum in the direction to the environmental
    air.
  • While the bone conduction stimuli evoke a higher
    velocity of perilymph along the basilar membrane
    in that ear, the evoked signal will be stronger.
  • Experts will say Webers lateralisation is
    directed towards the affected ear.

51
Or in case of a more complex case
Slechthorend - plus.nl
  • If the Eustachian tube remains permanently open,
    like f.i. in case of the PET syndrome, the voice
    of the patient creates also a varying pressure in
    the middle ear.
  • Under that pressure variations the eardrum will
    start to move and will not only transfer that
    motion to the ossicular chain, but will also put
    the perilymph in the cochlea into motion.
  • But now with the same phase as the bone
    conduction sound signal, so this PET sound
    stimulus contribution and the also existing
    normal bone conduction signal are added up and
    create a higher total signal.
  • Together with the impaired hearing mentioned
    before, the patient will hear his own voice
    louder and starts to speak at a lower level.

52
An utmost tragic hearing history
Slechthorend - plus.nl
  • End 1993 a woman got an enormous slam on her left
    ear. She developed not only in that ear, but in a
    somewhat moderate way also in her right ear an
    intense strong hyper sensitivity for all sounds
    above the minimum. Nobody believed her, so she
    was treated for almost 6 years as a psychiatric
    patient. Until she read in a tabloid that her
    hearing problems have a name Hyperacusis.
  • Now again after visiting a number of hearing
    experts during years she is still confronted with
    much skepticism and there is no adequate aid for
    her. Actually experts still doesnt believe her,
    because they dont see reasons why a left side
    acoustic trauma can also create hyperacusis on
    the right side. And they observe her more as a
    neurotic person than as someone with a serious
    hearing problem.
  • But with the perilymph push pull according to my
    cochlear model, hyperacusis is no longer
    something extravagant, but can be the result of
    overstretching the membranes on both sides. A
    completely normal phenomenon. Perilymph movements
    can be strongly enlarged, and after the squaring
    an utmost strong signal inside the cochlea can be
    evoked.

53
Meanwhile on the website www.slechthorend-plu
s.nl
Slechthorend - plus.nl
  • like the cases explained here, you can find a
    number of hearing phenomena that are explained in
    a logic and plausible way by using my proposed
    cochlear model.
  • And this list is still growing.

54
Not yet on this list but announced is an
explanation of the following phenomenon
Slechthorend - plus.nl
  • Binaural beat
  • Not as the result of mysterious activity in the
    brain according to the present hypothesis,
  • but as the result of the hydrodynamic
    cooperation between both hearing organs via the
    enclosed perilymph filling inside the
    cerebrospinal cavity.

55
What is Binaural beat ?
Slechthorend - plus.nl
  • Experiment
  • Via a headphone left ear stimulus f.i. 400 Hz
    and the right ear equally strong 410 Hz.
  • Together with EEG measurements of the
    Brainwaves
  • Results
  • Measured brainwave weak 10 Hz, modulated by 10
    Hz.
  • The signal is strongest if both offered
    frequencies are stimulating the ears in opposite
    phase and weakest if they are doing that in
    identical phase.
  • Present explanation
  • Binaural beats are auditory brainstem responses
    created in the superior olivary nucleus of each
    hemisphere.

56
As a hydrodynamic phenomenon?
Slechthorend - plus.nl
  • With 400 Hz frequency the left ear is pumping
    a part of the perilymph via the cochlear
    aqueducts and the skull cavity in and out the
    right ear.
  • At the same moment the right ear does the same
    with 410 Hz in and out the left ear.
  • That pumping to one ear from the other one
    results into two influences on the perilymph
    movement in that one ear
  • A bone conduction signal with the other
    frequency.
  • And with the pump frequency a periodical
    varying of the content of the perilymph duct in
    the cochlea, which functions as follows
  • If perilymph is pumped out of the skull cavity
    into the cochlea and at the same time the
    airborne sound signal presses the oval window
    inwards, the round window will bend out to a
    maximum and will also be stressed at a maximum,
    resulting in Smaller vibration deflections,
    hence weaker signals. In case the airborne sound
    is just pulling, while the other signal is
    pushing, the vibration possibilities become at
    the highest level.

57
And this results in
Slechthorend - plus.nl
  • Out of this movement possibilities per ear the
    velocity signal is squared Bernoulli and again
    modified. While using goniometric formulas, this
    results in the following frequency combinations

There are found brainwaves of 10 and 20 Hz !
  • Together forming the 10 Hz brainwave modulated
  • with 10 Hz.

58
Consequences of this
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  • A patient, who has on one side a no longer
    functioning auditory nerve, but a still
    completely intact mechanical cochlear system
  • Shows at the same side of his head still
    brainwaves due to the binaural beat
    experiments.
  • Which can be measured in an objective way with an
    EEG.
  • So a prove of this cochlear model can be obtained.

This is almost the decisive test for this
cochlear model !
59
Final conclusion
Slechthorend - plus.nl
  • In case this test is successful, I am convinced
    that I have offered you here a view on

The holy grail of our auditory sense
If not, than I can start to enjoy my
pension. Thank you for your attention.
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