Warm
Up- 5 mins to study
for Eye Quiz
Word Bank
Retina
 Rods
 Cones
 Thalamus
 Occipital (visual)
cortex
 Optic Nerve
 Fovea

Transduction
 Cornea
 Pupil
 Iris
 Lens
 Accommodation

Chapter 5: Sensation pt. 2
Mariachi or Old Folks
3 Faces In One
9 People?

Old Man or Lovers Kissing
A Young Woman or…
A Grouchy Clown
A Clown…
Or a Circus
Color Constancy

Human Beings
maintain Color
Constancy:
perceiving familiar
objects as having
consistent color,
even if lighting
changes to alter the
wavelength given off
by the object.
Context Affects Color
 We
only retain
color constancy
when the context
remains the same.
 Same color will look
different when
compared in
different contexts.
Sense 2: Hearing (Audition)
The loudness of a sound is determined
by a waves amplitude (height.)
 The frequency, number of complete
wavelengths that pass a point in a
given time, determines the sounds
pitch: the tones highness or lowness.

Hearing Threshold
Hearing is
measured in
decibels.
Zero
decibels is
considered
the
threshold of
hearing.

Parts of the Ear
Outer Ear:
 Job:
Gather sound waves to eardrum.
 Parts: auditory canal and eardrum.

Middle Ear
 Job:
To Amplify and concentrate the vibrations
onto cochlea’s oval window.
 Parts: Ossicles, made up of three tiny bones:
hammer, anvil, and stirrup (malleus, incus, and
stapes)

Inner Ear
 Job:
To change sound waves into neural
impulses
 Parts: Oval Window, Cochlea, Basilar
Membrane, Hair Cells.
Process of Hearing
1.
2.
3.
Your outer ear
channels sound
waves to the eardrum
or tympanum.
Your eardrum vibrates
with sound waves
This causes 3 tiny
bones called the
ossicles (the hammer,
anvil and the stirrup) of
your middle ear to
vibrate
Process of Hearing
4. The vibrating stirrup
pushes against the
oval window of the
cochlea in the inner
ear. The cochlea is fluid
filled and waves are
created.
5. Inside the cochlea is a
basilar membrane with
hair cells that are bent
by the vibrations and
are transduced into a
neural impulse
Process of Hearing
6. Hair cells synapse with
auditory neuron whose axons
form the auditory nerve
7. The auditory nerve transmits
sound messages though your
medulla, pons and thalamus
to the auditory cortex of the
temporal lobe.
 What cell is triggers neural
impulses in the eye?
Inner Ear and Vestibular Sense
The semicircular canals are
connected to the cochlea
by the vestibular sacs.
 The semicircular canals
contain substance that
move when our head
rotates or tilts and allows
us to maintain our
vestibular sense: sense
of our body movement
and position

How Do We Perceive Pitch: 2
Theories
Hemholtz’s Place Theory: argues we hear
different pitches because different sound
waves trigger activity at different places
in the cochlea’s membrane…easily explains
high pitches since these pitches are highly
localized.
 Frequency Theory: We sense pitch by the
basilar membrane in cochlea vibrating at
the same rate as the sound. Explains low
pitch well….

 Volley
Principle- alternate firing to get over
1000 fires per sound
How Do We Locate Sounds
Why is
Having 2
Ears
Important?
Parallel Processing
Just
like with vision, audition
involves parallel processing
Time
difference
Intensity
memories
Hearing Loss
Conductive Hearing
Loss: hearing loss
caused by damage to the
mechanical system that
conducts sound waves
to the cochlea like
eardrum and ossicles.
 Solution to Conductive
Hearing Loss?

 Hearing
aid
Hearing Loss
Sensorineural
Hearing Loss:
damage caused
to cochlea’s
receptor cells
(hair cells) or
auditory nerves.
 Solution?

 Cochlear
Implant
Older People Suffer Most Hearing Loss
With High Frequency Sounds

On a separate pieces of paper put these words
in the correct order of how we hear and in
your own words tell me how we hear
DO NOT JUST COPY YOUR NOTES
Cochlea
 Stirup
 Hammer
 Sound waves
 Neural impulse
 Transduction
 Oval window

Anvil
 Ossicles
 Outer ear
 Eardrum/tympanu
m
 Basilar membrane
 Hair cells

Warm up – page 34
1. What is the difference between Sensor
neural and conductive hearing loss?
 2. Why do we have 2 ears?
 3. What is the purpose of function of the
hammer, anvil and stirrup?
 4.How do we transform sound waves into
perceived sound?
 What is the Place Theory?
 What is the Frequency Theory?

Touch
 Premature Babies
 Monkeys
 Skin sensations are a variation of
the basic 4
Pressure
Warmth
Cold
Pain
Sense #3: Touch
 Pain
Is a Good Thing!
 Gate Control Theory:
 theory that the spinal cord contains a
neurological “gate” that blocks pain
signals or allows them to pass on to the
brain
 “gate” opened by the activity of pain
signals traveling up small nerve fibers
 “gate” closed by activity in larger fibers
or by information coming from the brain
Social Influence On Pain
-Pain is both a
physiological and a
psychological
phenomenon.
-Depending on
symptoms, doctors may
use drugs, surgery, etc.
or relaxation training,
thought distraction.
Example: Lamaze
Method
Memories of Pain
More to our memories of pain than the pain we
experienced.
 People tend to overlook duration of pain and
instead concentrate on its peak moments and
how much pain they felt at the end.
 What do doctors do because of this?

Taper
down procedures
Senses 4 & 5: Taste and Smell

Why are Taste and Smell
studied together?
Taste
 4 Basic Sensations
 Sweet
 Sour
 Salty
 Bitter
 200
taste buds
 Reproduce every 1 or 2 weeks
 Older= decrease in taste buds
 Smoking and Alcohol= decrease in
taste buds
 Taste
Taste and Smell
and Smell are both
chemical senses.
 Tongue is central muscle
for taste which contain
taste buds.
 Smell runs through
receptor cells in nasal
cavity which are send
neural signals to the
olfactory bulbs in the
Smell
5
million receptor cells at the top of
your nasal cavity
 Detect 10,000 odors
 Decreases with age
 Have your own chemical signature
Smell
Nasal Cavity brings the smell up to your
receptors
 Receptor cells send the message to the
brain’s olfactory bulb
 Then to the temporal lobe’s primary smell
cortex
 Parallel Processing

Olfactory
nerve
Olfactory
bulb
Nasal
passage
Receptor cells in
olfactory membrane
Smell and Emotion
 Sense
of smell activates
areas in limbic system
involved in emotion and
memory.
 Smells can often evoke
memories of the past or
emotional experiences
more often than most
other senses.
Sensory Restriction
 People
born without access to a
sense, compensate with development
of stronger other senses.
 Sensory Restriction has produced
mixed results depending on context:
Early Experiments: disorientation,
hallucinations, etc.