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LEARNING Long lasting change in behavior, due to experience
Classical Conditioning crash course khanacademy • Ivan Pavlov – studied digestion of dogs – noticed dogs would salivate before they were given food (triggered by sounds, lights etc…) – concluded: dogs must have LEARNED to salivate in response to stimuli other than the food Click above to see a reenactment of Pavlov’s experiments.
Classical Conditioning • This is passive learning. • First, we need an unconditional relationship. ü Unconditioned Stimulus (UCS) - something that elicits a natural, reflexive response ü Unconditioned Response (UCR) - response to the UCS
Classical Conditioning • Next, we choose a neutral stimulus (something that by itself elicits no response). • We present the stimulus with the UCS a whole bunch of times.
Classical Conditioning • After a while, the body begins to link together the neutral stimulus with the UCS. • Acquisition
Classical Conditioning • We know learning takes places when the previously neutral stimulus provokes the response. • At this point, the neutral stimulus is now a conditioned stimulus (CS) and the unconditioned response becomes the conditioned response (CR).
Classical Conditioning • Acquisition is not permanent. • The moment the CS is no longer associated with the UCS, we have EXTINCTION.
Spontaneous Recovery • Sometimes, after extinction, the CR will randomly appear when CS is presented.
Classical Conditioning Examples See if you can identify the UCS, UCR, CS and CR. Click above to see classical conditioning as portrayed in The Office. Click above to see classical conditioning in a high school student’s own “experiment”.
TEST YOUR KNOWLEDGE: UCS ? UCR? CS? CR? You typically take showers in the locker room after practice. During one such shower, you hear someone flushing a nearby toilet. Suddenly, extremely hot water rushes out of the shower head, causing serious discomfort. As you continue the shower, you hear another toilet flush and immediately jump out form under the shower head.
UCS? UCR? CS? CR? Your mother prepared a tuna sandwich for your lunch. Unfortunately, the mayonnaise she used had been left out too long and was spoiled. Not long after eating, you felt extremely nauseated and had to rush to the bathroom. Thereafter, the mere mention of a tuna sandwich sent you scurrying to the bathroom with a hurting stomach.
UCS? UCR? CS? CR? You were happy when you heard your family's plan to go to a water show. Then you heard the weather report, which predicted temperatures exceeding 100 degrees. As you watched the water skiers perform routines to blaring organ music, you got more and more sweaty and uncomfortable. Eventually, you fainted from the heat. After the family outing you could never again hear organ music without feeling a little dizzy.
Classical Conditioning and Humans • John Watson brought classical conditioning to psychology with his “Baby Albert” experiment. Click the image to the left to see footage from the “Baby Albert” experiment.
Generalization and khanacademy • Something is so similar to the CS that there is the CR. Discrimination • Something is so different from the CS there is no CR.
Garcia and Koelling Study • Studied rats / conditioning • Conclusion #1 - Even if sickened several hours later, rats developed taste aversions. • Conclusion #2 – Rats developed aversions to taste, but not sight, sound, etc. CS UCS CR Loud Noise Radiation (nausea) NONE Sweet Water Shock NONE Sweet Water Radiation (nausea) Avoid Water
Taste Aversions • In cases of food paired with nausea & sickness, conditioning is incredibly strong. ü even when food and sickness are hours apart
Contingency Model • Robert Rescorla – revised Pavlov’s classical conditioning model – starts with the realization that something must account for the ability to discriminate between stimuli – emphasized the role of cognitive processes during acquisition – said that classical conditioning “is not a stupid process by which the organism willy -nilly forms associations between any two stimuli that happen to occur. ”
Operant Conditioning start @ 5: 47 The Learner is NOT passive. Learning based on consequence!!! khan academy Big Bang
The Law of Effect Click picture to see a better explanation of the Law of Effect. • Edward Thorndike • Locked cats in crates • Behavior changes because of its consequences • Rewards strengthen behavior • If consequences are unpleasant, the stimulusreward connection will weaken. • Called the whole process instrumental learning
B. F. Skinner • Operant Conditioning • Emphasized nurture (environment) and the minimal role of free-will / mental processes. • Used a “Skinner Box” (Operant Conditioning Chamber) to prove his concepts.
Reinforcers khanacademy • A reinforcer is anything that strengthens (increases) a behavior Positive Reinforcement: • The addition of something pleasant Negative Reinforcement: • The removal of something unpleasant
Positively or Negatively Reinforced? Putting your seatbelt on. Faking sick and avoiding AP Psych class. Studying for a test. Taking an aspirin. Breaking out of jail. Receiving a kiss for doing the dishes.
+ Positive Reinforcement Punishment Gives something to increase the likelihood that the behavior will be repeated (the subject wants thing/condition) Gives something to decrease the likelihood that the behavior will be repeated (the subject does not want this thing/condition) Negative Takes something to increase the likelihood that the behavior will be repeated (the subject does not want this thing/condition) Takes something to decrease the likelihood that the behavior will be repeated (the subject would like to have this thing/condition)
Punishment • A stimulus meant to decrease a behavior Positive Punishment • addition of something unpleasant. Negative Punishment (Omission Training) • removal of something pleasant • Punishment works best when it immediately follows behavior and is harsh!
How do we actually use Operant Conditioning? khanacademy • Sometimes, we use a process called shaping. • Shaping is reinforcing small steps on the way to a desired behavior. These small steps are called approximations.
Chaining Behaviors • Subjects are taught to link multiple responses together in order to get a reward. Click picture to see a rat chaining behaviors Click to see a cool example of chaining behaviors. .
Same Terminology as Classical Conditioning If I wanted to reinforce a toddler’s dancing by giving him lollipops when he dances, identify the following… • Acquisition • Extinction • Spontaneous Recovery • Generalization • Discrimination
Primary v. Secondary Reinforcers Primary Reinforcer • things that are intrinsically rewarding Secondary Reinforcer • things we have learned to value (because they are associated with primary enforcers) • Money is a special secondary reinforcer called a generalized reinforcer (because it can be traded for just about anything)
Token Economy • Every time a desired behavior is performed, a “token” is given. • They can trade “tokens” in for a variety of prizes (reinforcers) • Used in homes, prisons, mental institutions and schools.
Reinforcement Schedules khanacademy How often do you give the reinforcer? • Every time the desired behavior is exhibited or just sometimes when it is?
Continuous v. Partial Reinforcement Schedules Continuous • Reinforce the behavior EVERY TIME the behavior is exhibited. • Usually done when the subject is first learning to make the association. • Acquisition comes really fast, but so does extinction. Partial • Reinforce the behavior only SOME of the times it is exhibited. • Acquisition comes more slowly. • But is more resistant to extinction. • FOUR types of Partial Reinforcement schedules.
Ratio Schedules (Responses) Fixed Ratio • Provides a reinforcement after a SET number of responses. Variable Ratio • Provides a reinforcement after a RANDOM number of responses. • Very hard to get acquisition but also very resistant to extinction. Fixed Ratio- She gets a manicure for every 5 pounds she loses.
Interval Schedules (Time) Fixed Interval Variable Interval • Requires a SET amount • Requires a RANDOM of time to elapse before amount of time to elapse giving the reinforcement. before giving the reinforcement. • Very hard to get acquisition but also very resistant to extinction. Fixed Interval: She gets a manicure for every 7 days she stays on her diet.
Which type of reinforcement schedule? • • Fixed Ratio Variable Ratio Fixed Interval Variable Interval
Negative vs. Positive Reinforcement Primary vs. Conditioned Ratio Schedules Concepts / Components Interval Negative Punishment Operant Conditioning Positive Response / Stimulus Associations Thorndike Law of Effect / Cat Experiments Skinner Box / Rat & Bird Experiments People
Latent Learning • Edward Tolman – demonstrated the concept using rats/mazes & reinforcers. • Learning is not always immediately observable in behavior (“latent” means hidden). • Learning doesn’t completely depend on consequences. • cognitive maps – a mental representation of one’s environment
AP PRACTICE A child has learned her grandparents ignore rather than reward her tantrums. Which of the following operant principles are the grandparents using to control the child’s behavior? a. b. c. d. e. Positive reinforcement Negative reinforcement Delayed reinforcement Extinction Stimulus substitution
Insight Learning • Wolfgang Kohler Chimpanzees / Boxes & Bananas experiment • Learning takes place through the “ah ha” experience (gaining “insight”). • Weakens the behaviorist argument (emphasis on external, behavior / consequence relationship)
Images from Kohler’s chimpanzee experiments
Observational Learning khanacademy crash course • Albert Bandura - Bo. Bo Doll experiment • Learning through modeling behavior from others. • Observational learning + Operant Conditioning Principles = Social Learning Theory • Implications of Bandura’s findings? Click pic to see footage from the Bobo Doll experiment.
Associative Learning Classical Conditioning S+S Operant Conditioning R+S Latent Learning Other Insight Learning Observational Learning