► Chapter 3: SENSORY PROCESSES ◄

SENSING AND PERCEIVING: A FEW BASIC CONCEPTS A. Sensation: is the conversion of energy from the

environment into a pattern of responses by the nervous system.

Perception: is making sense of that information (sensation)

B. Transducer: a mechanism that converts energy from one form

to another

Problem: neurons use only chemical & electrical energy

Outside World Sensory System Sensation/Perception

Electromagnetic Vision Seeing Pressure Audition Hearing Chemicals Gustation Tasting Chemicals Olfaction Smelling

Mechanic Somatosensation Touch Transduction

C. SENSORY THRESHOLDS AND ADAPTATION: 1. Psychophysics: The study of how physical stimuli are

translated into psychological (sensory) experiences

2. Absolute Thresholds: is the minimum amount of stimulation

that an organism can detect 50% of the time.

Exam 2 Notes -2-

3. Difference Thresholds - Just Noticeable Difference (jnd):

is the smallest difference in the amount of stimulation

that a specific sense can detect

4. Signal Detection Theory: A decision making process

5. Sensory Adaptation: Involves a gradual decline in

sensitivity to prolonged stimulation (you get use to it).

Dark Adaptation: eyes become MORE SENSITIVE to light in

low illumination.

• VISION •

THE EYE A. STRUCTURES THAT FOCUS VISUAL IMAGES 1. Cornea: serves as protection for the structures behind it

2. Lens:

- Transparent eye structure - FOCUSES the light rays falling on the retina (focuses the

visual image)

3. Iris: ring of muscle whose pigmentation gives the eye its

characteristic color (blue, brown, hazel)

Exam 2 Notes -3-

B. RETINA: neural tissue lining the inside back surface of the eye (light energy is changed to neural energy)

1. Photoreceptors:

- Cells that are light-sensitive - Two types rods & cones

a) Rods: specialized visual receptors that play a key role

in NIGHT VISION and PERIPHERAL vision

b) Cones: specialized visual receptors that play a key role in DAYLIGHT VISION and COLOR VISION

2. Optic Nerve:

- Collection of axons from the retina that connect the eye

with the brain.

3. Blind Spot: The area at which the optic nerve exits the

retina.

4. Fovea: tiny spot in the center of the retina that contains

PRIMARILY CONES

III. THEORIES OF COLOR VISION:

A. Trichromatic: (Young-Helmholtz)

- The human eye has THREE TYPES of receptors with differing

sensitivities to different wavelengths

Primary Hues: red, green, & blue

Exam 2 Notes -4-

B. Opponent-Process:

- Color is perceived in three channels, where an either-

or-response is made to pairs of ANTAGONISTIC colors

• HEARING AND THE OTHER SENSES • I. HEARING A. Cochlea (snail like structure):

- Fluid filled

B. Basilar Membrane: runs the length of the cochlea

- Contains hair cells which convert physical stimulation

into neural signals

II. CHEMICAL SENSES A. Taste and smell are stimulated by chemical molecules

B. Taste and smell are interrelated

C. Taste Buds: Fire neural impulses when they absorb

chemicals dissolved in your saliva

D. Hair Cells:

Exam 2 Notes -5-

III. POSITION SENSES: A. Vestibular Sense: Important for posture and SENSE OF

BALANCE

B. Kinesthetic Sense: monitors the POSITION of the VARIOUS

PARTS of your body

• SELECTION AS PART OF ATTENTION •

A. STIMULUS FACTORS (Bottom up) Physical characteristics of

the stimuli

A) Contrast D) Motion B) Intensity E) Novelty-Familiarity C) Size F) Repetition

B. PERSONAL FACTORS (Top-Down):

Mental Set: Predisposed way to perceive something (an expectation).

C. PERCEPTUAL ORGANIZATION

1. Contour: the point at which a change in brightness occurs.

2. Gestalt: Interested in how perception enable us to group

and organize stimuli together

Exam 2 Notes -6-

3. Figure-Ground Relationship:

Figure:

Ground:

Reversible Figure: drawing that is compatible with two

different interpretations that can shift back and forth

D. STIMULUS FACTORS: Characteristics of stimuli that help us

perceive them as being organized together in one figure

1. Proximity (or contiguity): things that are near each

other seem to belong together.

2. Similarity: We tend to group stimuli that are similar

3. Continuity: Principle of continuity reflects our tendency

to follow in whatever direction we have been led.

4. Common Fate: Elements that move together tend to be

grouped together.

5. Closure: Grouping of elements so that they create a sense

of closure, or completeness.

SUBJECTIVE CONTOURS: (special case of closure)

6. Simplicity: law of "pragnanz" we tend to group elements

that combine to form a good figure.

Exam 2 Notes -7-

• PERCEPTION OF DEPTH AND DISTANCE • + We do not directly sense Depth and Distance; it is

something we PERCEIVE.

+ Rely on indirect predictors of distance (binocular & monocular cues)

+ Construction of three-dimensional vision is one of the

brain’s most important activities.

A. BINOCULAR CUES (ocular cues): are cues about distance

that one obtained by comparing the differing views of the two

eyes.

a) Retinal Disparity: (Principle Binocular depth cue) Objects project images to slightly different locations on

your right and left retinas.

b) Convergence (Another Binocular cue): Sensing your eyes

converging toward each other as they focus on closer objects.

c) Accommodation: is the changing of the shape of the lens by

the ciliary muscles to focus images on the retina.

B. MONOCULAR CUES (Pictorial Cues): are depth cues that can be

seen with ONE eye

a. Linear Perspective: parallel lines that run away from the

viewer seem to get closer together

b. Interposition: The shapes of near objects overlap or mask

those of more distant ones.

Exam 2 Notes -8-

c. Relative Size: If separate objects are expected to be of

the same size, the larger ones are seen as closer.

APPARENT MOTION

Image moves across the retina (stimulates successive rods &

cones)

• CONSTANCY OF PERCEPTIONS • - Organize & Interpret stimuli

1. Size Constancy: Our tendency to view objects as stable in

size even though the size of their image changes when they

are viewed from different distances.

2. Shape Constancy: compensates for distortions due to the

three dimensional nature of the world (e.g. door)

3. Brightness Constancy: white shirt sensed as gray at night

but perceived as white.

• GEOMETRIC ILLUSIONS & IMPOSSIBLE ILLUSIONS •

Illusion: perception that is at odds with what we know as

physical reality. 1) They do not depend upon our ignorance 2) They do not "occur" at the retina 3) They do not depend on movement of the eye.

Exam 2 Notes -9-

► Chapter 5: CLASSICAL CONDITIONING ◄

I. Learning: is a relatively durable change in behavior or

knowledge that is due to experience.

II. Reflex: unlearned automatic response that occurs in the

presence of a specific stimulus

III. CLASSICAL CONDITIONING (Pavlovian Conditioning OR

Respondent Conditioning): is a type of learning in which a

neutral stimulus acquires the ability to evoke a response that

was originally evoked by another stimulus.

Example of classical conditioning

Exam 2 Notes -10-

A. Conditioning: is the simplest form of learning it involves

learning associations between stimuli and responses.

1) Unconditioned Stimulus (UCS): Is a stimulus that evokes

an unconditioned response without previous conditioning.

2) Unconditioned Response (UCR): Is an unlearned reaction to

an unconditioned stimulus that occurs without previous

conditioning.

3) Conditioned Stimulus (CS): Is a previously neutral

stimulus that has, through conditioning, acquired the

capacity to evoke a conditioned response.

4) Conditioned Response (CR): Is a learned reaction to a

conditioned stimulus that occurs due to previous conditioning.

B. Orienting Reflex: a simple, unlearned response of orienting

toward, or attending to a new or unusual stimulus.

C. Habituation: is when an organism comes to ignore a stimulus

of no consequence.

Exam 2 Notes -11-

IV. CLASSICAL CONDITIONING PHENOMENA A. Acquisition: Is the formation of a new conditioned response

tendency.

B. Extinction: The GRADUAL WEAKENING and DISAPPEARANCE of a

conditioned response tendency.

C. Spontaneous Recovery: is the reappearance of an

extinguished response AFTER a period of NONEXPOSURE to the

conditioned stimulus.

D. Generalization: occurs when an organism responds to new

stimuli that are SIMILAR to the ORIGINAL STIMULUS used in

conditioning

E. Discrimination (OPPOSITE OF GENERALIZATION): Occurs when

one DOES NOT RESPOND to stimuli that are similar to the

original stimulus used in conditioning.

V. CLASSICAL CONDITIONING IN EVERYDAY LIFE: A. ADVERTISING CAMPAIGNS SOMETIMES TRY TO TAKE ADVANTAGE OF

CLASSICAL CONDITIONING:

Unconditioned Stimulus: Unconditioned Response:

Conditioned Stimulus: Conditioned Response:

Exam 2 Notes -12-

B. PHOBIC DISORDERS:

- Example of Classical Conditioning in everyday life.

C. Systematic Desensitization: the use of classical

conditioning in which a state of relaxation is paired with

anxiety-producing stimuli to alleviate irrational fears.

D. CONDITIONED TASTE AVERSION: Conditioned ONLY through the

pairing of taste stimuli & nausea.

VI. JUST WHAT IS LEARNED IN CLASSICAL CONDITIONING? * Conditioning is now viewed as the LEARNING OF RELATIONSHIPS

that exists among events in the world.

VII. APPLYING CLASSICAL CONDITIONING TO YOUR STUDY OF PSYCHOLOGY - Find a special place to study - RESERVED ONLY for

studying. - Common locations can act as conditioned stimuli and come to elicit conditioned responses.

Exam 2 Notes -13-

● OPERANT CONDITIONING ●

I. OPERANT CONDITIONING (Instrumental Learning): is a form of

learning in which voluntary responses come to be controlled by

their consequences.

Law Of Effect (Thorndike): if a response in the presence of a

stimulus leads to satisfying effects, the association between

the stimulus and the response is strengthened.

II. COURSE OF CONDITIONING: A. Shaping: The reinforcement of closer & closer approximation

of the desired response

B. Acquisition: an increase in response rate due to the

process of operant conditioning.

C. Extinction: Gradual weakening & disappearance of a response

tendency because the response is no longer followed by a

reinforcer.

D. Spontaneous Recovery: extinguished response returns after a

rest interval.

Exam 2 Notes -14-

III. REINFORCEMENT A. Reinforcement: occurs when an event following a response

strengths the tendency to make the response & can be

thought of as a reward.

1) Positive Reinforcer: occurs when a response is

strengthen because it is followed by the arrival of a

(presumably) pleasant stimulus.

2) Negative Reinforcer: a response is STRENGTHENED because

it is followed by the removal of a (presumably)

unpleasant stimulus.

TWO WAYS TO INCREASE A BEHAVIOR: we can a. give someone something that they "like" (positive

reinforcement) OR

b. take away something that they "dislike" (negative

reinforcement)

3) Primary Reinforcers: are stimulus events that are

inherently reinforcing because they satisfy biological

needs for humans.

4) Secondary Reinforcers: are stimulus events that acquire

reinforcing qualities by being associated with primary

reinforcers.

5) Continuous Reinforcement Schedule (CRF): EVERY instance of a designated response is reinforced.

Exam 2 Notes -15-

6) Intermittent Reinforcement Schedules: Occurs when a designated response is reinforced only some of the time.

a) Fixed-Ratio Schedule (FR): the reinforcer is given

after a FIXED number of non-reinforced responses

b) Fixed-Interval Schedule (FI): reinforcement is given

for the FIRST RESPONSE that occurs AFTER a FIXED

INTERVAL has elapsed.

c) Variable-Ratio Schedule (VR): the reinforcer is given after a VARIABLE NUMBER of non-reinforced responses.

d) Variable-Interval Schedule (VI): The reinforcer is

given for the first response after a variable time

interval has elapsed.

B. PUNISHMENT: Occurs when an event that follows a response

weakens or suppresses the tendency to make the response. 1) Positive Punishment: a response is followed by the presentation of aversive stimulus

2) Negative Punishment: a response is followed by the

removal of a pleasant stimulus.

Reinforcement Punishment

Positive

Negative

Exam 2 Notes -16-

C. GENERALIZATION:

D. DISCRIMINATION:

E. Instinctive Drift: occurs when an animal's innate response

tendencies interfere with conditioning processes.

Walden Two – B. F. Skinner

You can reinforce your own actions for studying!

• COGNITIVE APPROACHES TO LEARNING •

COGNITIVE APPROACHES TO LEARNING: Learning that need not

involve an observable behavior.

Latent Learning: learning that is NOT shown in behavior at

the time it occurs.

Cognitive Map: a mental representation or a mental picture of

a physical environment due to learning.

Exam 2 Notes -17-

Social Learning Theory: learning can take place through

imitation and observation of models

Learning the consequences of one's behavior by observing the consequences of someone else's behavior

Vicarious Reinforcement:

Vicarious Punishment:

Exam 2 Notes -18-

► Chapter 4: LEVELS OF CONSCIOUSNESS ◄

A. Consciousness: all mental experiences

B. Three Levels of Consciousness (Freud):

1) Conscious:

2) Preconscious:

3) Unconscious:

C. Subliminal Perception: stimulus presented below the threshold

for conscious perception.

• VARIETIES OF CONSCIOUSNESS • A. SLEEP

1. Electroencephalogram (EEG):

a) BETA Activity: Wide awake

b) ALPHA Activity: EEG pattern, eyes closed, not

a sleep, calm and relaxed state

2. Electromyogram:

Exam 2 Notes -19-

3. STAGES OF SLEEP

Stage 1: Brief transitional stage usually last 5-10 min.

* ALPHA waves give way to THETA waves.

Stage 2: Characterized by brief burst of higher-frequency brain waves, sleep spindles-> fairly regular intervals * START to get DELTA WAVES

Stage 3: 20% of EEG activity DELTA WAVES

Stage 4: More than 50% of EEG DELTA WAVES

REM Sleep (Rapid Eye Movement):

* Deep stage of sleep Difficult to awaken a person

* EEG activity dominated by BETA WAVES * Stage where most dreaming occurs.

Atonia: Muscle tone is extremely relaxed, bodily movement

are minimal & sleeper is virtually paralyzed. ENTIRE SLEEP CYCLE RUNS ABOUT 90 Min.

6. Dreams:

Nightmares: are anxiety arousing dreams that lead to

awakening (usually from REM sleep).

Night Terrors: Abrupt awakening from Non-Rem sleep accompanied by intense autonomic arousal & feelings of panic.

7. Somnambulism (sleepwalking): occurs when a sleeping

person arises and wanders about in deep Non-REM sleep (stage 3 or 4).

Exam 2 Notes -20-

• VOLUNTARY ALTERATIONS OF CONSCIOUSNESS •

A. HYPNOSIS: an altered state of consciousness one enters

voluntarily. * Can produce sensory distortions & hallucinations HALLUCINATIONS: are perceptual experiences that occur

without sensory input.

1) SPECIAL PROCESS THEORY: Hidden Observer Theory:

HIGHWAY HYPNOSIS: person drives a great distance

responding to traffic signals & other cars with no recall of any consciousness effort to do so.

2) NONSTATE-VIEW THEORY:

B. MEDITATION: self-induced state of altered consciousness

C. ALTERING CONSCIOUSNESS WITH DRUGS

PSYCHOACTIVE DRUGS: Psychoactive Drugs are chemical

substances that modify mental, emotional, or behavioral

functioning.

Dependence:

Tolerance:

Withdrawal:

Addiction:

Drug Abuse:

Exam 2 Notes -21-

1) STIMULANTS: are drugs that tend to increase central

nervous system activation and behavioral activity.

a) Caffeine: found in may foods as well as many varieties of pain killers.

b) Nicotine: activate excitatory synapse in both CNS & PNS

c) Cocaine: elevates blood pressure & heart rate,

d) Amphetamines: (Norepinephrine & Dopamine)

2) DEPRESSANTS: reduces one's awareness of external stimuli,

Alcohol:

3) Opiates, Heroine, & Barbiturates:

a) Opiates (Narcotics): can reduce or eliminate sensation of pain, tend to ignore real-world stimuli.

Examples: Heroin & Morphine

b) Barbiturates: synthetically produced sedatives

4) HALLUCINOGENS: Are a diverse group of drugs that have a

powerful effect on mental and emotional functioning.

- Distortions in sensory and perceptual experiences. LSD (Lysergic Acid Diethylamide):

5) MARIJUANA: A mild, relaxed euphoria, accompanied by

enhanced sensory awareness and a distorted sense of time.