Sensation/Perception
 Absolute Threshold
 Minimal amount for a stimulus to be detected
 Just Noticeable Difference (difference threshold)
 Minimum amount of distance between two stimuli that can
be detected
 Example: playing pairs of tones of varying volumes
 Weber’s Law
 Size of JND is in constant proportion of the size of the initial
stimulus weight lifting 1/30
Signal-Detection Theory
 Involves decision processes as well as sensory processes
 Hit – signal present, person reports sensing it
 Miss – signal present, participant did not sense it
 False Alarm – signal absent, participant reports sensing
it
 Correct Rejection – signal absent, participant did not
report sensing it
Transduction
 Converted from outward stimulus to the
electorchemical signal
The Eye
 Lens
 Focuses light rays on retina
 Pupil
 Light goes through (black part)
 Retina
 Absorbs light, processes images, sends visual info to the brain
 Rods
 Night vision & peripheral vision
 Cones
 Day time vision & color
 Fovea
 Tiny spot in the center of the retina, cones only, visual activity
greatest at these spots
Parallel Processing
 Simultaneous extraction of different kinds of info from
the same input
 Example: Parvocellular channel handles color and
perception, and magnocellular handles brightness
Color Theory
 Young-Helmholtz or Trichromatic Theory
 The eye has 3 receptors with different sensitivity to different
light waves
 Blue, red, green
 Opponent Process Theory
 Color perception depends on receptors that make antagonistic
responses to three pairs of colors
 Red v. Green
 Yellow v. Blue
 Black v. White
 After image
 Stair at a red dot, turn to white paper is green
Feature Analysis
 Bottom-up processing
 Individual elements to whole
 Top-down processing
 Whole to individual
 People perceive the whole world before seeing the
individual letters
Phi Phenomenon
 Illusion of movement created by presenting visual
stimuli in rapid succession
 Separate still pictures projected rapidly one after the
other, leads you to believe motion is occurring
 Max Wertheimer
Formulating Perception
 Distal Stimuli
 Stimuli that lie in the distance (exists in environment)
 Proximal Stimuli
 Stimulus energies that impinge directly on sensory
receptors (on the retina)
Hearing
 Cochlea
 Fluid filled coiled tunnel contains the receptors for
hearing
 Basilar membrane
 Runs length of spiraled cochlea holding auditory
receptors
 Auditory receptors = hair cells
Theories of Hearing
 Place Theory
 Hermann von Helmholtz
 Perception of pitch corresponds to the vibration of
different portions, or places, along basilar membrane
 Different hairs set up by different sounds (wrong)
 Frequency Theory
 Perception of pitch corresponds to the rate, or frequency
at which the entire basilar membrane vibrates
 The whole membrane vibrates in unison in response to
sound
Senses
 Olfactory - smell
 Habituation – we become accustomed to stimulus notice
it less over time
 Dishabituation – small change in stimulus causes to
notice it again
 Gustation – taste
 Tactile – touch
 Law of Pragnanz – we see things in its simplest form
Gate-Control Theory
 Pain can only be felt if it can pass through a gate in the
spinal cord
 Louisville’s Kevin Ware
Consciousness
 Subliminal perception
 Preconscious processing
 Presented with a stimulus so rapidly we do not detect
 Conscious
 Pre (sub) conscious
 Unconscious
 Repression – forgettabout it
 Freudian slips - oops!
Sleep
 Melatonin – chemical associated with sleep
 Circadian Rhythm




24 hour biological cycle found in humans
We fall asleep at certain points of the day
Sleep (body temp drops) awake (body temp rises)
Occurs even without time cues
Electroencephalograph
(EEG)
 Beta


13 – 24 cps – normal waking thought, alert
Dreaming
 Alpha

8 – 12 cps – deep relaxation, blank mind, meditation
 Theta

4 – 7 cps – light sleep
 Delta


Less then 4 cps – deep sleep
Stage 4
Dreaming
 REM




Stage 5
Paradoxical sleep – brain waves resemble when we are awake even
though we are in a deep sleep
Manifest – storyline of dream
Latent – symbols underlying meaning
 NREM

Stages 1 – 4
 Sleep Spindles


Stage 2
Brief bursts of higher-frequency brain waves
Sleep Disorders
 Narcolepsy
 Sleep apnea
 Nightmares v. Night terrors
 Narcolepsy
 Sleep walking (somnambulism)
 Insomnia
Activation-synthesis
hypothesis of dream
 Dreams are a product of our awareness of neural
activity due to sensory input while we are sleeping.
Neural repair, consolidation of memories, and protein
synthesis seem to occur during dreams
Dreaming
 Manifest content – Story line of dream
 Latent content – underlying meaning
Classical Conditioning
 Ivan Pavlov, John Watson & Rosalie Rayner
 UCS – stimulus creates a unconditioned response without
previous conditioning
 UCR – unlearned reaction to an unconditioned stimulus
occurs without previous conditioning
 CS – previously neutral stimulus that has through
conditioning acquired ability to create a CR
 CR – Learned reaction
Classical Conditioning
 Acquisition – initial stage of learning, pairing items
 Discrimination – Do not respond to new stimuli as did
with the old
 Generalization – responds to similar stimuli
 Extinction – gradual weakening/disappearance of CR
 Spontaneous Recovery – reappearance of extinguished
response
Classical Conditioning
 Second Order Conditioning
 Previous CS now used as UCS
 Higher Order Conditioning
 a conditioned stimulus functions as if it were an
unconditioned stimulus
 New conditioned responses are built on the foundation
of already established conditioned response (Red light
paired with bell)
Garcia Effect
 Conditioned taste aversion (CTA)
 Garcia Effect
 Animals eat food and as a result become nauseated by
drug/radiation will not eat that food again
 Highly resistant to extinction
Instrumental Conditioning
(Operant Conditioning)
 Edward Thorndike
 Law of Effect – behavior is more likely to recur if
reinforced
 Cat and the puzzle box
Instrumental Conditioning
(Operant Conditioning)
 B.F. Skinner
 Shaping – rat near the lever, touching lever, pressing lever
 Differential reinforcement of successive approximations –
only rewarded for pushing the lever
 Primary (natural) reinforcement – Events that are inherently
reinforce behaviors because they satisfy biological needs
 Food, sex, warmth, water
 Secondary Reinforcement - Events that acquire reinforcing
qualities by being associated with primary
reinforcement
 Examples: Money, good grades, attention, flattery, praise,
cars, jewelry
Two Kinds of Stimuli
Positive
Positive Reinforcement
Negative
Negative Punishment
• Add something that
follows the stimulus
•Removal of an
appetitive
•Appetitive (good).
•Grounded
•Timeout
Positive Punishment
• Add an aversive (bad) that
follows the stimulus
•Spanking
Negative Reinforcement
• Removal of an aversive
•Seatbelt noise
•Doing chores
Ratio - #
Fixed
Schedules
(Regular)
Reinforced after a fixed number of
responses
Interval - Time
Reinforcement of first response after
a fixed amount of time ahs passed.
• Paid for every 10 pairs of
jeans I sell at the GAP.
• Pick up check every two
weeks.
• Two yellow cards =
ejected from the volleyball
game.
• Cram for a test, but study a
lot less afterwards.
Variable
Reinforcement after varying
number of responses
Reinforcement of first response after
varying amounts of time.
Schedules
• Slot machines
• Surprise quiz in class.
• Door to door sales
• Dialing a friend on the
phone and getting a busy
signal.
(Irregular)
More Terms . . .
 Token Economy
 Artificial economy based on . . . (you guessed it) tokens
 Tokens act as secondary reinforcer and can be used for
purchasing primary reinforcer (food).
 Learned Helplessness
 Consistent effort fails to bring reward
 Example: Study for test get bad grade
Social Learning (Vicarious
Learning)
 Bobo Doll
 Learning from watching others
Cognitive Processes
 Edward Tolman
 Trained rats to run maze to obtain food (reward)
 Cognitive Map
 Tolman concluded that rats had a “cognitive map” of
where the food was and that it was “over there” (not just
a series of right-left responses
Latent Learning
 Learning that is not expressed until needed
 Rats in Tolman’s experiment