3.1 Learning

• A lasting change in behavior or mental processes as the result of an experience
– Behavior can be observed
– Mental processes are more difficult to study

Instincts
• Instincts are unlearned behaviors due to evolutionary programming that are found in almost all members of a species
• Example…bears hibernate, geese migrate, salmon swim upstream to spawn
• Humans…debated, but…
– Grasping reflex, sucking reflex, pull hand away from fire, blinking
Learning
• Represents a significant evolutionary advance over instinctive behavior
• Enables humans to acquire new knowledge that can be transferred from one generation to another

• Ivan Pavlov (1849-1936)
• Russian (later Soviet) physiologist who was awarded a Nobel Prize in 1904 for his research on the digestive system of dogs
• While conducting experiments…Pavlov noticed that his dogs tended to salivate before food was actually delivered to their mouths

• Spent 3 decades…532 experiments to studying classical conditioning
• Discovered classical conditioning (because first to be extensively studied in psych)
• Condition = learned
• Elicit = cause / produce / bring forth

5 Components of Classical
Conditioning
1. Unconditioned Stimulus (UCS) (US)
- natural stimulus that reflexively elicits a response without the need for prior learning
- Pavlov used food as the US because it produced naturally occurring salivation reflex
- Unlearned stimulus = automatic

5 Components of Classical
Conditioning
2. Unconditioned Response (UCR) (UR)
- Unlearned response that is elicited by an US
- In Pavlov’s experiments, salivation was the UR

5 Components of Classical
Conditioning
3. Neutral Stimulus (NS)
- Any stimulus that produces no conditioned response prior to learning
- In Pavlov’s experiments a ringing bell was originally a neutral stimulus.

5 Components of Classical
Conditioning
4. Conditioned Stimulus (CS)
- The CS was originally the NS.
- When systematically paired with the US, the
NS becomes a conditioned (learned) stimulus as it gains the power to cause a response
- In Pavlov’s experiments, the ringing bell became a CS when it began to produce the same salivating response that the food once produced

5 Components of Classical
Conditioning
5. Conditioned Response (CR)
- A CR is a learned response elicited by the CS
- Pavlov called the process by which a CS elicits a
CR “acquisition”
- In Pavlov’s experiments, he paired the ringing bell with food. Originally a NS, the ringing bell became a CS when the dog reacted with a CR by salivating
- The dog’s salivation was both an UR and CR
- **CC is most efficient when the CS immediately precedes the US**

• Toilet flush and shower
• US – hot water
• UR – jumping back
• NS – originally the toilet flush
• CS – becomes the toilet flush
• CR – jumping back

• Taught baby Albert to fear a rat
• NS - Rat
• Reflex: US (loud noise)  UR (cry)
• Acquisition: NS + US  UR
• Acq. Demonstrated:
– CS (rat)  CR (cry)
• Shows how phobias and human emotions develop

• Gradual weakening of a conditioned behavior when the CS is not followed by the US
• Example…Pavlov presented the ringing bell without food --- as a result, the ringing bell gradually lost its power to elicit the CR of salivation

• The reappearance of an extinguished CR after a time delay
• Example…Pavlov discovered that after a period of time, his dogs began salivating when they heard the sound of the bell **Note – the
CR reappears at a lower intensity
• This shows how difficult it can be to eliminate a CR

• Occurs when stimuli that are similar to the original stimulus also elicit the CR (when a new stimulus was not paired with the US
• Example…Pavlov found that a dog conditioned to a low-pitched tone would also respond to a high-pitched tone

• Ability to distinguish between two similar stimuli
• Example…students have learned different responses to the sound of bells in the classroom, cell phones, and front doors
• Example…gardeners demonstrate discrimination when they respond differently to weeds and to flowers

• Example…
• A young boy is bitten by his neighbors dog
• He runs away when he sees any neighborhood dog (Generalization)
• He still enjoys playing with his family's pet collie (Discrimination)

• Aka – second-order conditioning
• A CS from one learning trial is paired with a new
• The new US becomes the new CS capable of eliciting the CR even though it has never been paired with the US
• Example… Pavlov CC a dog to salivate to the sound of a ticking metronome . He then paired the metronome with a black square. After several pairings, the black square produce salivation even though it had never been paired with food.

A rat has already been conditioned to associate the blue stick with a cat odor(US). A red light is flashed on before the blue stick is placed in its cage. The rat displays a second-order conditioned response when just the red tight is turned on.

• A CC dislike for and avoidance of a particular food that develops when an organism becomes ill after eating the food
• Many people have experienced vivid examples of taster aversion

• Aka – Aversive Conditioning
• NS: food
• Reflex: US (stomach virus)  UR (vomiting)
• Acquisition: NS + US  UR
• Acq. Demonstrated:
– CS (food)  CR (vomiting – sick)

• John Garcia experiments (1917)
• Conducted experiments to demonstrate that taste aversions could be produced in laboratory rats
• NS (saccharin-flavored water)
• US (drug) -> UR (gastrointestinal distress)
• After recovering from illness, the rats refused to drink the flavored water (taste aversion)

• Garcia’s findings challenged two basic principles of CC
– 1. conditioning only required a single pairing
– 2. conditioning does not always need to be separated by seconds – he separated the stimuli by several hours
**demonstrated there are biological constraints on conditioning!

• Example – Wolves and Sheep

• Limitations on Classical
Conditioning…
– CC focuses on existing reflexive behaviors that are automatically elicited
– Learning, however, involves new behaviors or voluntary actions that classical conditioning cannot explain

• His studies on baby chicks and cats were the first systematic investigation of animal learning
• Focused on how voluntary behaviors are influenced by their consequences

• Responses that lead to satisfying outcomes are more likely to be repeated
• Responses followed by unpleasant outcomes are less likely to be repeated

• Behaviorist who believed that psychologists should focus on observable behavior that could be objectively measured and verified

• Formulated the principle of Operant
Conditioning
• OC – any “active behavior that operated upon the environment to generate consequences”
• OC is a learning process in which behavior is shaped and maintained by consequences
(rewards or punishments) that follow a response
CC (S  R) / OC (R  S)

• The box is a chamber that includes at least one lever, bar, or key that the animal can manipulate.
• When the lever is pressed, food, water, or some other type of reinforcement might be dispensed.
• Other stimuli can also be presented including lights, sounds, and images.
• In some instances, the floor of the chamber may be electrified

Operant Conditioning: Reinforcement
• Reinforcement occurs when a stimulus
(reinforcer) follows an active behavior or response
• The reinforcer increases the probability that the behavior or response will be repeated

• Behavior is followed by the addition of reinforcing stimulus
• Stimulus increases the probability that the response will occur again
• NOTE – positive does not mean “good” or
“desirable”
• Positive like a “+” sign
– Indicates a response is strengthened because something is added

• Flawless performance is school play (the operant) / your drama coach applauds and exclaims “Bravo!” reinforcing stimulus)
• You earn a “A” on an AP Psychology Test (the operant) / your teacher writes you a letter
(reinforcing stimulus))

• Behavior or response is followed by the removal of an adverse stimulus
• NOTE - negative does not mean “bad” or
“undesirable”
• Negative like a “-” sign
– Indicates that a response is strengthened because something is subtracted or removed

• You take out the garbage (the operant) to avoid your mother’s repeated nagging (aversive stimulus)
• You put on sunscreen (the operant) to avoid getting sunburned (aversive stimulus)
• You give your little brother a candy bar (the operant) to prevent him from crying (aversive stimulus)
• Your little sister is crying (the operant), you hug her and she stops crying (aversive stimulus)

• David Premack
• Stated that the opportunity to engage in a preferred activity can be used to reinforce a less-preferred activity

• You enjoy playing video games far more than studying for the ACT.
• Knowing this, you tie the less-preferred activity (studying for the
ACT) to your preferred activity (playing video games)
• You enjoy eating ice cream for dessert far more than eating vegetables.
• Knowing this, your mother ties the lessdesired activity (eating veggies) to your preferred activity
(eating ice cream)

• Primary Reinforcers
– Naturally reinforcing for a species
– Ex…food, water, shelter, sex
• Secondary Reinforcers
– Gains effectiveness by a learned association with primary reinforcers
– Ex…money

• Token Economy
– Individuals rewarded with tokens that can act as secondary reinforcers.
– The tokens can be redeemed for rewards and priveledges
– Elementary Teachers – gold stars

• Reinforcement schedule in which all correct responses are reinforced
• Responses extinguish faster when they are learned through this

• Technique of strengthening behavior by reinforcing successive approximations of a behavior until the entire correct routine is displayed
• Used by athletic coaches and animal trainers

• Rewarding of some, but not all, correct responses
• Advantages
– Most efficient way to maintain behaviors already learned
– Are very resistant to extinction
– Example – Gambling (very difficult habit to extinguish)

Ratio Schedules
• Based on number of responses
• Fixed ratio
• Variable ration
Interval Schedules
• Based on responses made within a certain time period
• Fixed interval
• Variable interval

• Reinforcement occurs after a predetermined set of responses
– Produce high response rates (brief drop-off after reinforcement)
• Examples…
– an employer pays workers every three baskets of fruit
– Mario Bros – 100 coins = life

• Reinforcement is unpredictable because the ratio varies
• High response rates and resistant to extinction
• Examples…
– Casino slot machines
– Golf
– Door-to-door salesman

• Reinforcement occurs after a predetermined time has elapsed
– Moderate response rates followed by a flurry of activity near the end of each interval
• Examples…
– Employers paying employees every two weeks
– Teachers who give a quiz every week
– Baking a cake

• Reinforcement occurs unpredictably since the time interval varies
– Produce low but steady response rates
• Examples…
– Teachers and pop quizzes
– Fishing
– Parent attending to children crying

• Process by which a behavior is followed by an aversive consequence that decreases the likelihood the behavior being repeated.
• Is NOT the same as reinforcement
– Punishment decreases the likelihood of a behavior
– Reinforcement increases the likelihood of a behavior

• Application or adding of an aversive stimulus after a response
• Examples…
– You arrive late for work (operant) you are docked pay (aversive stimulus)
– You show off your knowledge by answering all the teacher’s questions (operant) a popular girl makes a snide remark about you (aversive stimulus)

• Removal or subtraction of a reinforcing stimulus
(privilege)
• NOT negative reinforcement!
– Negative punishment makes a behavior less likely to happen
– Negative reinforcement makes a behavior more likely to happen
• Examples…
– You arrive at work late (operant) and are sent home without pay (loss of reinforcing stimulus)
– You show off your knowledge by answering all the teacher’s questions (operant) and the popular girl doesn’t invite you to her party (loss of reinforcing stimulus)
– Person who was caught driving while intoxicated also loses her driver’s license

• Can produce undesirable results (fear, hostility, aggression)
• Often produces temporary change
• Can produce Learned Helplessness
– Occurs when a learner feels that it is impossible to escape punishment
– Leads to passive feeling hopelessness that may lead to depression
• Example…
– A student is doing poorly in AP Psych
– “No matter what I do, I’m going to fail”

• Should be delivered immediately after the offensive behavior
• Should be certain
• Should be limited and sufficient so that it “fits the crime”
• Should focus on the behavior, not the character, or the offender

Comparing CC and OC
Classical Conditioning
• Pioneers
– Pavlov and Watson
• Types of Behavior
– Involuntary responses
• Timing of Stimuli
– Precedes the response
– S  R
• Use of Rewards/Punishment
– Does not use
Operant Conditioning
• Pioneers
– Thorndike and Skinner
• Types of Behavior
– Voluntary responses
• Timing of Stimuli
– Follows the response
– R  S
• Use of Rewards/Punishment
– Based on