Psych sensation and perception - hear

Audition

results from changes in air

pressure; the sense of sound perception

sound wave

The pattern of the changes in air

pressure during a period of time

A sound wave’s amplitude determines

loudness

its frequency determines its

pitch

1. Sound waves hit the

outer ear

2. Sound waves travel down the

auditory canal

3. Sound waves get to the

eardrum (beginning of the middle ear)

Eardrum vibrates and transfers the

vibrations to the

ossicles (3 tiny bones in middle ear)

5. ossicles transfer the vibrations to the

Oval Window (part of the cochlea in the inner ear)

6. Vibrations create pressure waves in

the

cochlear fluid

7. Hair cells start to bend and send

   information to the

auditory nerve

8. It sends the information to the

auditory nerve which goes to the

thalamus and then auditory cortex

Hair Cells =

Primary Auditory Receptors

Cochlear Implants

Helps people who have severe

difficulty with hearing due to the

loss of inner ear hair cells

• Doesn’t amplify sound but

  stimulates the auditory nerve

Vestibular sense

perception of balance determined

by receptors in the inner ear

Temporal coding

used to encode low-

frequencies (up to ~4,000 Hz) auditory

stimuli in which the firing rates of cochlear

hair cells match the frequency of the sound

wave

Place coding

a mechanism for encoding

high-frequency auditory stimuli in which

the frequency of the sound wave is

encoded by the location of the hair cells

along the basilar membrane

Gustation

the sense of taste

Olfaction

the sense of smell

Taste Buds =

Taste Receptors

Stimulated taste buds send

signals to the thalamus, and

then to the frontal lobe of the

brain -

which produces the

experience of taste.

Order of taste-

1. A substance hits the taste buds

2. Taste buds send signals to the thalamus

3. Then the signal is routed to the insula and then to the frontal

lobe

Five Basic Taste Perceptions

Every taste experience is composed of a mixture of five

basic qualities:

○ sweet

○ sour

○ salty

○ bitter

○ umami (Japanese for “savory” or “yummy”)

■ monosodium glutamate (MSG)

come into contact with a

thin layer of tissues embedded

with smell receptors called the

olfactory epithelium

Odorants

Olfactory epithelium

a thin layer

of tissue within the nasal cavity

that contains the receptors for smell

Olfactory bulb

the brain center for

smell located below the frontal

lobes

Haptic sense

the sense of touch

○ Conveys sensation of temperature, pressure, and pain

○ Touch is perceived through the skin, our largest sensory

organ

Skin Sensory Receptors

Anything that makes contact with our skin

provides tactile stimulation.

Pain Perception

Pain is part of a warning system that stops you from continuing activities that may harm you.

● Two kinds of nerve fibers have been identified for pain

Fast fibers for

sharp, immediate pain

Activated by strong physical pressure and temperature extremes

Slow fibers for chronic,

dull, steady pain

■ Activated by chemical changes in tissue when

skin is damaged

Gate control theory

We experience pain when pain

receptors are activated, and a neural

“gate” opens in the spinal cord and

allows pain signals to be carried by

nerve fibers to the brain

What impacts pain perception?

drug treatments, cognitive states, mental processes