sensation unit slides

Sensation & Perception unitm12-17

m12 - Introduction to Sensation

Psychophysics beginnings

Top-down vs Bottom-Up Processing

Absolute threshold

Signal detection

Absolute threshold

Signal detection

“Yes there are two paths that you can go by, but in the long run there’s still time to change the road you’re on”

Stairway to Heaven

“Yes there are two paths that you can go by, but in the long run there’s still time to change the road you’re on”

Stairway to Heaven

“Oh here’s to my sweet Satan. The one whose little path would make me sad, whose power is Satan.”

Stairway to Heaven

“Oh here’s to my sweet Satan. The one whose little path would make me sad, whose power is Satan.”

Stairway to Heaven

Another One Bites the Dust

“Another one bites the dustAnother one bites the dustAnother one bites the dust”

Another One Bites the Dust

“Another one bites the dustAnother one bites the dustAnother one bites the dust”

Another One Bites the Dust

“It’s fun to smoke marijuanaIt’s fun to smoke marijuanaIt’s fun to smoke marijuana”

Another One Bites the Dust

“It’s fun to smoke marijuanaIt’s fun to smoke marijuanaIt’s fun to smoke marijuana”

“subliminal” associations

“subliminal” associations

“subliminal” associations

“subliminal” associations

“subliminal” associations

“subliminal” associations

Difference threshold (Just noticeable difference)

Weber’s Law

Light must differ by 8%

Weight by 2%

Tone by 0.3%

Sensory adaptation

Sensory attention

Cocktail party effect

x

What do you see?

What do you see?Who

What do you see?Who

m13 - Vision

Hue = wavelengthIntensity = amplitude

Normal Nearsighted Farsighted

Ganglion Cell Activity

Ganglion Cell Activity

Ganglion Cell Activity

Feature Detection Cells

Visual Processing

Vis

ual P

roce

ssin

g pr

oced

ure

What do you see?

What do you see?

What do you see?

What do you see?

What do you see?

Young-Helmholtz trichromatic theory

additive color mixing

Color Vision

Color Vision

Opponent-Process Theory

after-image effects . . .

Color processing seems to occur in two stages:

Retinal cones respond like Young-Helmholtz trichromatic theory

Signal processed via opponent-process in the central nervous system

Col

or C

onst

ancy

m14 - Hearing

Amplitude = volumeFrequency = pitch

Amplitude = volumeFrequency = pitch

Echolocation

Place Theory

Frequency Theory

Conduction Hearing Loss

Sensorineural Hearing Loss

m15 - Other Senses

TouchPressure, warmth, cold, and pain

• Only pressure has identifiable sensory neurons

Pain is adaptive

• Hyperalgesia and Congenital Analgia

Phantom Limb

Gate Control Theory

Taste

• Sweet, sour, salty, bitter ... and umami

• Super-tasters

Vestibular Sense vs Kinesthesis