Transcript Sensation and Perception

Sensation and
Perception
Sensation vs. Perception

Sensation
 Energy

 receptor cell  transduction
Perception
 Interpretation
of sensation
Sensory Thresholds
Absolute threshold
 Difference threshold
 Just noticeable difference
 Weber’s law

 How

sensitive are you?
Sensory adaptation
Visual System

Psychologists have studied vision more
than any other sense
The Visual System

Light enters the eye
through the cornea
The Visual System

Light enters the eye
through the cornea

Neural impulses are
created in the retina
by receptor cells
 rods
and cones
Cells in the Retina
Trichromatic Theory
Trichromatic Theory

There are three types of cones:
 red,
green, and blue
 Perceived colors are result from differing
amount of light absorbed by the three types of
cones.
Opponent-Process Theory

Color-sensitive ganglion cells are arranged
in opposing cells
 Red-green,
yellow-blue, black-white

Activation of one cone inhibits another

May explain some kinds of afterimages
Gestalt Psychology

Gestalt psychologists investigated the
principles that guide how we create a
coherent perceptual experience

Figure-Ground Distinction
Proximity
Proximity – Take 1
Proximity – Take 2
Similarity
Continuation
Closure
Good Figure
Common Fate
Depth Perception

Binocular Cues
 Retinal
disparity
Depth Perception

Binocular Cues
Depth Perception

Monocular Cues
 Object
size/Size constancy
Depth Perception

Linear Perspective
Depth Perception

Relative size
and linear
perspective
Depth Perception

Detail

Interposition
Depth Perception

Texture Gradient
Depth Perception

Shadows
Depth Perception

Aerial
Perspective
Depth Perception
Motion Parallax
 Demonstration

Hearing
Sound…

How do we hear?
Hearing Loss
Conductive Hearing Loss
 Nerve Deafness

Pitch Perception
Place Theory
 Frequency Theory

 Volley
principal
Auditory Perception
 Localizing Sound

Smell
Taste

Receptor cells are in buds on tip, sides,
and back of the tongue.
Kinesthetic and Vestibular Senses

Kinesthetic sense
 Muscle
movement, changes in posture, and strain on
muscles and joints
 Stretch receptors and golgi tendon organs

Vestibular sense
 Equilibrium
& body position in space
 Semicircular canals of inner ear & vestibular sacs
The Skin Senses

Receptors in the skin
 Touch,
Pressure, Temperature,
Pain

Information goes to brain
through two routes
 Through
medulla and
thalamus to sensory cortex, or
 From thalamus to reticular formation.
Pain

Gate-control theory
A
gate in spinal cord permits, prevents pain
signals from passing
Other impulses can overwhelm
 Perception can influence pain
