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Learning. Learning: a relatively permanent change in an organism’s behavior due to experience Are reflexive actions learning?. Conditioning: The practice of learning associations Classical Conditioning: Learning to associate two stimuli, allowing us to anticipate events
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Learning: a relatively permanent change in an organism’s behavior due to experience • Are reflexive actions learning?
Conditioning: The practice of learning associations • Classical Conditioning: Learning to associate two stimuli, allowing us to anticipate events • Operant Conditioning: Learning to associate our behavior with a consequence (good or bad) and thus learning to repeat (or not) that behavior
Classical Conditioning • Ivan Pavlov: Russian scientist • The famous salivating dog experiment
Pavlov broke down the structure of conditioning like this: • Unconditioned Response (UR) – unlearned, natural instinct • Unconditioned Stimulus (US) - triggers the UR • Conditioned Response (CR) – Response to the new stimulus • Conditioned Stimulus (CS) – previously irrelevant stimulus that now triggers a response
Unconditioned Stimulus (UCS) • UCS: A stimulus that automatically-without conditioning or learning- provokes a reflexive response. • In Pavlov’s experiment, food was used as the UCS because it produced a salivation reflex. • Classical conditioning cannot happen without UCS. The only behaviors that can be classically conditioned are those that are produced by unconditioned stimulus.
Unconditioned Response (UCR) • UCR: A response resulting from an unconditioned stimulus without prior learning. • In Pavlov’s experiment, the UCR was the dog salivating when its tongue touched food. • Realize that the UCS-UCR connection involves no learning or acquisition.
From Unconditioned to Conditioned • During acquisition, a neutral stimulus is paired with the unconditioned stimulus. • After several trials the neutral stimulus will gradually begin to elicit the same response as the UCS. • Acquisition: The learning stage during which a conditioned response comes to be elicited by the conditioned stimulus. =
Conditioned Stimulus • A CS is the originally neutral stimulus that gains the power to cause the response. • In Pavlov’s experiment, the bell/tone began to produce the same response that the food once did.
Conditioned Response • A CR is a response elicited by a previously neutral stimulus that has become associated with the unconditioned stimulus. • Although the response to the CS is essentially the same as the response originally produced by the UCS, we now call it a conditioned response.
Pavlov’s Conclusions Unconditioned Response (UCR) Unconditioned Stimulus (UCS) Conditioned Response (CR) Conditioned Stimulus (CS) because of because of
Taste Aversions • First, dream up a the perfect bowl of soup, one that you would rate a “9” on a 9 point scale
Now imagine that the soup was served to you in an ordinary bowl, but had been stirred by a thoroughly washed, used flyswatter. How much would you like to eat that soup?
If that flyswatter were brand new, how much would you like to eat the soup?
If the soup was first stirred with a thoroughly washed but used comb, how much would you like to eat it?
If the soup was served in a thoroughly washed, used dog bowl, how much would you like to eat it?
Now fantasize about your favorite cookie, again one that would rate a 9.
How much would you like to eat this cookie if you’d dropped it on the grass first?
How much would you like to eat it if a waiter had taken a bite first? an acquaintance? a good friend?
1. Eighty-two percent of Rozin’s participants rated the “clean-flyswatter soup” a 4 or less; they would dislike eating it. 2. Fifty-eight percent disliked this bowl of soup. Since the flyswatter is brand new, it has less of an association with insects. However, the idea that the soup had been stirred by an object that might meet a fly in the future was enough to make some people pass it up. 3. Seventy-six percent disliked this soup. Presumably, the thought of human hair is slightly less disgusting than insect contamination.
4. Seventy-one percent disliked soup served in a dog bowl. 5. Only 34 percent would want to pass up this cookie. There’s no assurance of perfect cleanliness, but grass itself has few negative associations for most of us. 6. Eighty-four percent would reject this cookie after a waiter had taken a bite. Only 31 percent would refuse it after an acquaintance had taken a bite, and just 16 percent, if a friend had taken a bite.
Watson took a a baby named Albert and conditioned him to be afraid of white furry objects using Pavlov’s techniques. Watson & Raynor with Little Albert
5 Conditioning processes • Acquisition – initial learning • Extinction – diminishing response • Spontaneous recovery – reappearance of a CR after a time • Generalization – tendency to respond to stimuli similar to the CS • Discrimination – ability to distinguish between CS and irrelevant stimuli
Extinction • Extinction: The diminishing (or lessening) of a learned response, when an unconditioned stimulus does not follow a conditioned stimulus. • To acquire a CR, we repeatedly pair a neutral stimulus with the UCS. But, if we want to reverse this learning, we must weaken the strength of the connection between the two stimuli. • It is important to realize that extinction does not mean complete elimination of a response.
Spontaneous Recovery • Extinction merely suppresses the conditioned response, and the CR can reappear during spontaneous recovery. • Spontaneous Recovery: The response after a rest period of an extinguished conditioned response. • Spontaneous recovery is weaker than the original CR.
Acquisition (CS+UCS) Strength of CR Spontaneous recovery of CR Extinction (CS alone) Extinction (CS alone) Pause Classical Conditioning
Reinforcement Procedures • What if we could not distinguish between stimuli that were similar? • The bell ending class vs. fire alarm • The door bell vs. our cell phones • Discrimination: The ability to distinguish between two similar signals stimulus.
How to train birds to spoil college (or high school) football games • 1. Select your target school and wait until summer, when the football field won’t be in use • 2. Put on a shirt with black and white vertical stripes • 3. Spread birdseed all over the football field • 4. As birds flock to the football field and eat the birdseed, blow a whistle and leave • 5. Repeat steps 2-4 until the football season begins • 6. Wait for the payoff. With any luck, when the referee walks onto the field and blows his whistle to start the game, a flock of hungry birds should show up and disrupt the proceedings
Biological Predispositions • Conditioning takes place more easily when the subject is biologically predisposed to respond a certain way
Operant Conditioning • Associating actions with consequences (behavior operates on the environment) • Law of Effect: Rewarded behavior is likely to recur
B.F. Skinner • Operant Chamber (Skinner Box)
Shaping • Types of reinforcement • Positive • Negative • Primary • Conditioned
Reinforcement • A reinforceris a condition in which the presentation or removal of a stimulus, that occurs after a response (behavior), strengthens that response or makes it more likely to happen again in the future. • Positive Reinforcement: A stimulus presented after a response that increases the probability of that response happening again. • Ex: Getting paid for good grades
Negative Reinforcement • Negative Reinforcement: The removal of an unpleasant or averse stimulus that increases the probability of that response happening again. • Ex: Taking Advil to get rid of a headache. • Ex: Putting on a seatbelt to make the annoying seatbelt buzzer stop. • The word “positive” means add or apply; “negative” is used to mean subtract or remove.
Examples of negative reinforcement • 1. Taking aspirin to relieve a headache. • 2. Hurrying home in the winter to get out of the cold. • 3. Giving in to an argument or to a dog’s begging. • 4. Fanning oneself to escape the heat. • 5. Leaving a movie theater if the movie is bad. • 6. Smoking in order to relieve anxiety. • 7. Following prison rules in order to be released from • confinement. • 8. Feigning a stomachache in order to avoid school. • 9. Putting on a car safety belt to stop an irritating • buzz. • 10. Turning down the volume of a very loud radio. • 11. Putting up an umbrella to escape the rain. • 12. Saying “uncle” to stop being beaten.
Punishment • A punishment is an averse/disliked stimulus which occurs after a behavior, and decreases the probability it will occur again. • Positive Punishment: An undesirable event that follows a behavior: getting spanked after telling a lie.
Punishment • Negative Punishment: When a desirable event ends or is taken away after a behavior. • Example: getting grounded from your cell phone after failing your progress report. • Think of a time-out (taking away time from a fun activity with the hope that it will stop the unwanted behavior in the future.)
Reinforcement vs. Punishment • Unlike reinforcement, punishment must be administered consistently. Intermittent punishment is far less effective than punishment delivered after every undesired behavior. • In fact, not punishing every misbehavior can have the effect of rewarding the behavior.
Punishment vs. Negative Reinforcement • Punishment and negative reinforcement are used to produce opposite effects on behavior. • Punishment is used to decrease a behavior or reduce its probability of reoccurring. • Negative reinforcement always increases a behavior’s probability of happening in the future (by taking away an unwanted stimuli). • Remember, “positive” means adding something and “negative means removing something.
