Transcript Document

Audition
Coding
Background
Basic
Cochlea
Physiology
Transduction
Generation
Auditory
Localization
Higher
Auditory
Brain
of
Pathway
Intensity
ofof
&
Activities
of
Action
the
Structure
Sound
Pathway
Mechanical
Cochlea
and
Potential
Involved
Frequency
of Auditory
Displacement
(AP) System
Cortical
Responses
Frequency
1.Auditory
Dorsal and
posteroventral cochlear nuclei
Transduction
in
Perception
Middle
Inner
ear
ear
Localization
of
sounds
above
3that
kHz
Circuit
6.
Depending
on
the
direction
hairs
bend,
Note:
Subjects
need
to
popped
their
ears
4.
Mechanism:
c.
Bones
in
the
Anteroventral
middle
ear
amplify
cochlear
the
Organ
of
Corti
1.
Consequence
of
the
mechanics
of
the
send
projections
to
the
inferior
colliculus
AP
Connections
occurs
at
to
the
the
level
brain
of
output
stem
ganglion
Processes
1.
Bending
ofear
these
is thethat
critical
4.
Depending
on
thecilia
direction
the event
hairs in
Outer
Monoaural
systems
2.
Ossicles:
Series
of
bones
in
a
small
air
1.
Medial
superior
olive
(MSO)
has
cells
that
c.
Dorsal
and
posterior
ventral
cochlear
nuclei
the
channel
will
either
be
opened
or
closed
when
they
go
up
in
an
airplane.
On
the
3.
Basilar
membrane
Process
Sound
pressure.
nuclear
firing
Pivot
rate
points
is
greater
that
act
for
as
sound
fulcrums.
with
3.
Circuit:
Anteroventral
cochlear
nucleus
1.
Structure
basilar
a.
Pathways
respond
to
sound
arriving
at
1.
Spiral
Multiple
1.Sound
ganglion
outer
waves
hair
sends
cells
move
projection
make
the
synaptic
to
the
c.
High
frequency
sounds
have
higher
energy
Sequence
overview:
the
transduction
of
sound
into
neural
signal
bend,
the
inside
of
the
hair
cells
will
either:
4.
From
the
thalamus,
this
information
5.
Structural
properties
of
the
basilar
Anatomy
Audition
1.
Pinna
1.
Converts
the
physical
movement
Intensity
filled
chamber.
Transfer
the
movement
of
receive
coincident
innervation
from
the
right
send
efferent
projections
to
the
contralateral
a.
Opening
the
channel
allows
K+
to
enter
and
ground
their
middle
ear
is
as
the
same
Mechanisms
for
detecting
interaural
time
3.
Functional
d.
4.
Oval
Eustachian
window
considerations:
tube:
is
smaller
Tube
and
that
Separates
scala
media
and
scala
tympani
1.
Mechanical
force
pushes
on
the
oval
window
1.Audible
variations
in
air
Malleus
higher
intensities
is
displaced
in
response
to
the
projects
directly
to
the
ipsalateral
lateral
a.
Outer
hair
cells
2.
Different
portions
of
the
basilar
one
ear
only
contact
cochlear
tympanic
with
nucleus
a
single
membrane.
ganglion
cell.
3.
Sound
waves
vary
in
two
ways:
Three
divisions
of
the
ear
and
can
displace
the
stiffer
part
of
the
basilar
1.
Physical
displacement
of
the
basilar
2.
Hairs
extend
above
the
reticular
membrane
a.
Depolarize
Neuronal
Background
organization
1.
Sound
does
not
bend
around
the
head
ascends
to
the
primary
auditory
cortex
(A1)
membrane
6.
Basilar
membrane
determine
establishes
the
way
it
responds
a
place
code
to
1.
Cross
section
5.
Movement
4.
Structures
of
the
within
fluid
in
the
the
cochlea
1.
Tympanic
membrane
(eardrum)
1.
Sense
of
hearing
a.Funnel
shaped
outer
ear
made
of
the
oval
window
into
neural
signal
1.
Firing
rate
of
individual
hair
cells
7.
Information
is
sent
to
a
relay
in
the
3.
Organ
of
corti
the
tympanic
membrane
into
the
movement
and
left
anteroventral
cochlear
nucleus
inferior
colliculus
depolarize
the
hair
cell
pressure
as
the
outside
environment.
As
differences
a.
Cochlea
the
connects
same
is
filled
pressure
the
with
air-filled
an
across
incompressible
middle
a
b.
Properties
are
very
important
for
audition
2.
Fluid
within
cochlea
is
incompressible
pressure
(compressions)
movement
i.
Sound
arising
of
the
tympanic
directly
lateral
membrane-to
the
superior
olive
(LSO)
b.
Inner
hair
cells
membrane
are
maximally
deformed
by
2.
Auditory
maps
2.
a.
There
Ganglion
are
make
two
cochlea,
synaptic
each
contact
projecting
with
a
to
2.
Tympanic
membrane
moves
a.Amplitude--intensity;
1.
Outer
peak
to
trough;
(near
the
base)
Auditory
receptors
Limitations
membrane
bends
the
stereocilia
and
come
in
contact
with
tectorial
membrane
b.
Hyperpolarize
1.
Isofrequency
Cochlea
transduces
bands
the
mechanical
2.
Directed
to
one
side
or
the
other
and
an
located
in
the
temporal
lobe
sound
in
which
different
locations
are
maximally
2.
Chambers
of
the
cochlea
causes
cochlea
a
response
are
not
in
rigid.
sensory
Basilar
neurons.
a.Moves
in
response
to
variations
2.
Mechanisms
within
ear
and
brain
of
skin
and
cartilage
2.
Takes
place
in
the
cochlea
3.
Activation
of
multiple
hair
cells.
thalamus(medial
geniculate
nucleus-MGN)
a.
Contains
auditory
receptor
cells
of
a
second
membrane
covering
a
hole
in
a.
Cells
within
the
MSO
are
organized
such
i.
Via
the
nucleus
of
the
lateral
leminiscus
b.
Closing
the
channel
stops
the
flow
of
K+
they
ascend,
air
pressure
is
lower
a
high
1.
Two
ears
separated
by
about
20
cm
fluid
smaller
ear
to
area
mouth.
results
It
in
Contains
a
greater
4.
is
continuous
between
scala
3.
Fluid
pushes
forward
2.
Molecules
are
displaced
bottom
listener,
moves
LSO
firing
towards
will
be
the
highest
inner
ear
on
and
that
i.
Indirectly
to
the
contralateral
lateral
c.
Tectorial
membrane
sound
of
different
frequencies
a.
Auditory
space
is
not
mapped
at
the
single
its
cochlear
inner
nucleus
hair
cell
(although
many
ganglion
the
ossicles.
perceived
as
differences
in
loudness
2.
Middle
d.
Lower
frequency
sounds
have
lower
energy
1.
Hair
cells
1.
System
works
well
for
sounds
that
have
2.Bending
of
cilia
opens
or
closes
K+
channel
3.
When
the
basilar
membrane
moves
in
5.
Changes
in
cell
potential
result
from
the
a.
Temporal
lobe
displacement
of
the
oval
window
into
intensity
difference
results
a.
A1
has
a
topographical
map
of
the
cochlea
deformed
Membrane
in
response
is
wider
at
to
apex
different
than
frequency
base
(5:1)
a.
Scala
vestibuli
6.
Signal
membrane
is
transferred
is
flexible
and
and
processed
in
air
pressure
that
translate
sound
in
our
environment
2.
Auditory
canal
Elements
a.
3.
Wave
of
higher
amplitude
has
8.
MGN
b.
Located
projects
in
to
the
the
scala
primary
media
auditory
the
bone
of
the
skull
(oval
window).
that
the
distance
from
the
respective
d.
Anterior
ventral
cochlear
nucleus
iscochlear
aThis
7.
In
response
to
be
depolarization
resulting
altitudes.
The
tympanic
membrane
will
i.
Diameter
of
your
head
b.
More
force
a
force
valve
(like
is
required
a
spiked
to
high
displace
heel)
fluid
vestibuli
and
scala
tympani
a.Conserves
wave
properties
of
the
sound
forward
leaving
a
corresponding
the
side
top
moves
towards
the
outer
ear.
superior
olive
via
an
inhibitory
neuron
d.
Reticular
membrane
3.
Hair
cells
that
are
selectively
activated
cortical
level.
Tonotopic
maps
are
created
at
cells
b.
Within
can
3.
the
Ossicles
contact
cochlear
the
move
same
nucleus
the
inner
membrane
this
hair
process
cell)
b.
Frequency:
Number
of
compressions
per
3.
Inner
and
displace
the
apex
end
a.
Stereocilia
frequencies
below
3
kHz
3.
When
K+
enters,
the
hair
cell
depolarizes
response
to
the
motion
of
the
stapes
opening
of
K+
channels
on
tips
of
stereocilia
2.
Neurons
within
these
bands
respond
to
a
neural
signal
i.
Specific
regions
(isofrequency
bands)
of
b.
sounds
Stiffness
of
the
membrane
decreases
from
b.width
Scala
tympani
by
a
series
bends
of
in
nuclei
response
in
the
to
sound
brain
stem.
into
meaningful
neural
signals
a.Channel
leading
from
the
pinna
Cochlea
b.
more
and
activates
more
hair
cortex
in
the
temporal
lobe.
The
bones
of
middle
ear
are
malleus
nuclei
varies
systematically
critical
component
of
a
brainstem
neural
from
influx
of
K+
bulge
out
because
the
pressure
in
the
2.
Detect
differences
as
small
as
10
msec
than
air
a.
Physical
connection
is
known
as
the
(i.e.
the
movement
of
the
fluid
has
frequency
area
lower
pressure
pulls
ii.
Excitation
the
top
of
from
the
incus
the
ipsilateral
towards
outer
originating
in
the
medial
nucleus
of
the
e.
Basilar
membrane
project
to
cochlear
nuclei
(brain
stem)
the
levels
of
the
inferior
colliculus
3.
branches
75%
of
all
hair
cells
are
outer
hair
cells
at
the
oval
window.
second;
pitch;
unit:
hertz
(1
cycle/second)
e.
Base
responds
to
high
frequency
and
the
4.
Depolarization
activates
a
Ca++
channel
Whole
complex
moves
as
a
unit
either
a.
Channels
are
mechanically
gated
fairly
similar
characteristic
frequencies
A1
are
activated
in
response
to
acoustical
base
to
apex
(like
a
diving
board)
c.
Scala
media
to
the
tympanic
membrane
Vestibular
apparatus
cells
in
a
given
area
(hammer),
incus
(anvil)
and
stapes
(stirrup)
i.
Length
of
the
axonal
connections
circuit
that
permits
the
detection
of
interaural
a.
Ca++
channel
is
activated
middle
ear
is
greater
than
the
outside
helicotrema
and
amplitude)
ear
anteroventral
and
pushes
cochlear
the
bottom
nucleus
towards
will
be
the is
trapezoid
body
(MNTB)
f.
Stereocilia
with
tonographic
specificity
3.
Highly
processed
auditory
information
a.
i.
Outer
Dorsal
alter
cochlear
the
stiffness
nucleus
of
tectorial
membrane
4.
Motion
at
the
oval
window
apex
responds
to
low
frequency
5.
Ca++
influx
causes
NT
release
towards
or
away
from
the
tectorial
membrane
b.
Flaps
that
are
connected
to
neighboring
stimulation
of
the
basilar
membrane
i.
Not
part
of
the
auditory
system
determine
which
MSO
cell
receives
coincident
time
differences
b.
Influx
of
Ca++
causes
the
release
of
environment.
When
they
yawn
or
swallow,
Causes
the
round
window
to
bulge
out
inner
maximal
ear.
Stapes
is
consequently
pushed
g.
Spiral
ganglion
a.
Specificity
is
conserved
all
the
way
to
then
relayed
to
the
medial
geniculate
4.
ii.
Only
Posterior
moves
5%
of
ventral
the
the
fibers
fluid
cochlear
in
in
the
the
cochlea.
auditory
nucleus
nerve
b. Lateral
motion
of
the
reticular
membrane
cilia
by
a
special
protein
molecule
ii.
Involved
in
balance
activation
by
action
potential
synaptic
vesicles
from
the
end
of
the
hair
cell
the
valve
in
the
tube
is
opened
and
the
forward
iii.
Inhibition
against
from
the
the
oval
contralateral
window
which
MNTB
is
the
cortex
nucleus
of
the
thalamus
are
iii.
from
Anterior
ventral
hair cells
nucleus
bends
theouter
stereocilia
Home
Exit
BASIM
ZWAIN LECTURE NOTES
pressure
is relieved.
compressed
will
be minimal
inward