Unit V: Learning

Learning A relatively permanent change in an organism’s behavior due to experience. We learn by association. Our minds naturally connect events that occur in sequence.

Associative Learning Learning that two events occur together. Two stimuli A response a nd its consequences.

Classical Conditioning A basic form of learning in which a stimulus that produces an innate reflex becomes associated with a previously neutral stimulus, which then acquires the power to elicit essentially the same response. The tapping of the yardstick on the desk causes you to flinch. .

Classical Conditioning Ivan Pavlov first demonstrated classical conditioning. His work provided a basis for later behaviorists like John Watson and B. F. Skinner.

Classical Conditioning and Pavlov’s Dogs: Hypothesis Dogs salivate when food is placed in their mouths (a reflex). Dogs salivate at the mere sight of food Hypothesis: Dogs can be trained, or conditioned, to salivate when exposed to an external, neutral stimulus.

Pavlov’s Methodology and Results Harness an untrained dog and place a vial to collect saliva. Sound a bell immediately before giving a bit of food Results: After a few trials, the dog salivates upon hearing the bell alone. Works with other stimuli as well; buzzer, metronome etc.

Pavlov’s Experiment Before conditioning, food (Unconditioned Stimulus, US) produces salivation (Unconditioned Response, UR). However, the tone (neutral stimulus) does not.

Pavlov’s Experiment During conditioning, the neutral stimulus (tone) and the US (food) are paired, resulting in salivation (UR). After conditioning, the neutral stimulus (now Conditioned Stimulus, CS) elicits salivation (now Conditioned Response, CR)

Pavlov’s Conclusions Unconditioned Stimulus (UCS) Unconditioned Response (UCR) Unconditioned Stimulus (UCS) Conditioned Response (CR) Conditioned Stimulus (CS) because of because of

Garfield

UNCONDITIONED STIMULUS Classical Conditioning UNCONDITIONED STIMULUS REFLEX ACTION will elicit a NEUTRAL STIMULUS CONDITIONED STIMULUS CONDITIONED RESPONSE elicit NO REACTION

Classical Conditioning Vocabulary Unconditioned Stimulus - UCS stimulus that unconditionally--automatically and naturally--triggers a response Unlearned. Unconditioned Response (UCR) Unlearned, naturally occurring response to the unconditioned stimulus salivation when food is in the mouth.

Classical Conditioning Vocabulary Conditioned Stimulus (CS) originally irrelevant stimulus that, after association with an unconditioned stimulus, comes to trigger a conditioned response Conditioned Response (CR) learned response to a previously neutral conditioned stimulus

Pavlov’s Homeroom

Other Aspects of Classical Conditioning Acquisition The first stage in classical conditioning. The phase associating a neutral stimulus with an unconditioned stimulus so that the neutral stimulus comes to elicit a conditioned response. In most cases, for conditioning to occur, the neutral stimulus needs to come just before the unconditioned stimulus. The time in between the two stimuli should be about half a second.

Other Aspects of Classical Conditioning Extinction Diminishing of a CR; when the CS occurs repeatedly without the UCS. The tone is heard several times without the food following.

Other Aspects of Classical Conditioning Spontaneous Recovery After a rest period, an extinguished CR spontaneously recovers. However, if the CS persists alone, the CR will become extinct again.

Other Aspects of Classical Conditioning Stimulus Generalization The tendency to respond to stimuli similar to the CS.

Other Aspects of Classical Conditioning Stimulus Discrimination Discrimination is the learned ability to distinguish between a conditioned stimulus and other irrelevant stimuli. Pavlov’s dogs did not respond to other sounds.

Cognitive Processes Early behaviorists believed that learned behaviors of various animals could be reduced to mindless mechanisms. However, later behaviorists suggested that animals learn the predictability of a stimulus, meaning they learn expectancy or awareness

Biological Predispositions Pavlov and Watson believed that laws of learning were similar for all animals. Therefore, a pigeon and a person do not differ in their learning. However, behaviorists later suggested that learning is constrained by an animal’s biology.

Conditioned Taste Aversions Can you think of a food that you once had a bad experience with that still produces a feeling of nausea when you encounter it? Can you think of a benefit to food aversions?

Taste-Aversion Learning The tendency to develop taste aversions appears to be part of our biological nature. Raises questions about Pavlov’s original Classical Conditioning theory.

John Garcia Garcia showed that the time duration between the CS and the US may be long (hours), but yet result in conditioning. Rats avoid drinking or eating from containers that made them sick. They associated flavored water with illness.

Pavlov’s Legacy Pavlov’s greatest contribution to psychology is isolating elementary behaviors from more complex ones through objective scientific procedures.

Applications of Classical Conditioning Watson used classical conditioning procedures to develop advertising campaigns for a number of organizations, including Maxwell House, making the “coffee break” an American custom.

Operant Conditioning Reward Punishment The consequences of behavior, such as reinforcers and punishments, influence the chance that the behavior will occur again. Behavior change is brought about by the consequences of behavior. Also a form of associative learning. An “operant” is an observable behavior that an organism uses to have an effect on their environment. Reward Punishment

B.F. Skinner The “founding father” of operant conditioning. American psychologist who based his entire career on the idea that the most powerful influences on behavior are its consequences.

Reinforcement Reinforcer: Any condition that follows and strengthens a response. Positive: Strengthens a response by occurring after the response and making the behavior more likely to occur again. Praise, attention, money, food etc. Negative: The removal of an unpleasant or averse stimulus. Negative = subtract or remove Using an umbrella in a rainstorm. Buckling your seatbelt.

The Skinner Box A simple device for studying the effects of reinforcers on laboratory animals. A box with a lever that an animal could press to obtain food. Could be set to control the timing and frequency of the reinforcement. Skinner called it an “operant chamber.”

Contingencies of Reinforcement The timing and frequency of rewards are crucial. Continuous Reinforcement: A reward is given for every correct response. The best strategy for teaching and learning new behaviors. Does have drawbacks: Accidental failure to reward a correct response could be misinterpreted. Will loose its reinforcing quality as the organism becomes satisfied.

Shaping Shaping: Used to create complex new behaviors because the teacher can continually “raise the bar” and increase the standards required for earning a reward. It tells the learner when progress is being made. An example of continuous reinforcement.

Intermittent Reinforcement The rewarding of some, but not all, correct responses. Also known as partial reinforcement. The best way to maintain behaviors that have already been learned. Helps resist extinction.

Schedules of Reinforcement The ratio schedule rewards a subject after a certain number of responses. Fixed Ratio (FR): Receive a reward after a specific number of responses. For example, one dollar for every 5 paper roses produced; piecework Variable Ratio (VR): Ever changing number of responses needed to receive a reward. Produces more responding than any other schedule of reinforcement. Slot machines.

Interval Schedules Reinforcement is based on responses made within a certain time period (instead of number of responses.) Fixed Interval (FI) Schedules: The time period between rewards remains constant. A monthly paycheck for example. Produces lowest level of responses. Variable Interval (VI) Schedules: The time interval between rewards varies. The most unpredictable of all. For example, fishing and elevators.

Schedules of Reinforcement Interval Ratio Fixed Variable

Primary and Secondary Reinforcers Primary: Reinforcers such as food, water and sex that have an innate basis because of their biological value to the organism. Secondary: Stimuli, such as money or grades, that acquire their reinforcing power by a learned association with a primary reinforcer. Also called Conditioned Reinforcers.

The Premack Principle A more-preferred activity can be used to reinforce a less-preferred activity. Sit still during a lesson so that you can run around during recess time afterwards. Discovered by David Premack.

The Problem of Punishment It is an aversive consequence used to weaken the behavior it follows. Acts as the opposite of reinforcement. Comes in two forms: Positive Punishment: requires the application of an averse stimulus. Negative Punishment: The removal of a reinforcer. Omission training. Must be administered consistently! Not punishing an occurrence of unwanted behavior can have the effect of rewarding it.

Problems with Punishment Punishment usually doesn’t work well in the long run. Why? The power of punishment to suppress behavior usually disappears when the threat of punishment is removed. Punishment triggers escape or aggression. Punishment makes the learner apprehensive, which inhibits learning new and better responses. Learned helplessness. Punishment is often applied unequally.

When Using Punishment When punishment is used it must be: Swift Consistent Limited in duration and intensity Clearly targeted on the behavior Limited to the situation in which the behavior occurred Giving clear, not mixed messages The most effective punishment is usually omission training.

Punishment vs. Negative Reinforcement An animal in a Skinner Box can turn off a loud noise by pressing a lever. Negative Reinforcement; Used to increase the behavior. A loud noise plays when the same animal presses a lever. Punishment; used to decrease the behavior.

Operant Conditioning Reinforcement Punishment Positive (Add) Chocolate Bar Electric Shock Negative (Remove) Excused from Chores No TV privileges

Skinner’s Work Play Skinner Video

Cognitive Explanations Many theorists believe not all learning can be explained with behaviorism. There is a cognitive element to some learning. Some learning must be explained as changes in mental processes, rather than just changes in behavior.

Insight Learning Wolfgang Kohler studied chimpanzees during WWI. He found: Once chimps solved a problem they would do the same thing in a similar situation. Chimps “thought out” their solutions ahead of time. They often reached a solution suddenly. He called this insight learning; a sudden understanding about what is required to solve a problem.

Insight Learning

Edward Tolman Latent Learning: learning that is not evident when it first occurs. Tolman’s rats had late rewards. The food rewards affected performance, but not learning. Rats had already developed a cognitive map; a mental representation of the environment (the maze.) They had developed it naturally, without reinforcement.

Observational Learning Observational Learning: learning how to perform new behaviors by watching others. Also known as social learning. Efficient and adaptive. Modeling is the process of observing and imitating a specific behavior.

Mirror Neurons Mirror neurons in our brains fire not only when we experience or do something, but also when we see someone else do or experience the same thing. We feel disgust when we see someone react to the taste of sour milk. May partly provide a biological basis for observational learning.

Bandura’s Study Children are particularly influenced by the adults and peers who act as models for appropriate behavior in various situations. Bandura showed preschool school children a film of an adult and a large “Bobo” doll. The children who saw the adult rewarded for aggression toward the doll showed the most aggressive acts in their own play. Vicarious Learning: a kind of observational learning in which a person is influenced by seeing or hearing about the consequences of other people’s behavior.

Social Learning Theory Some key aspects of Bandura’s theory include: People learn from observation of others, however, this can depend on the amount of attention that is given to the behavior. The person whose behavior is being observed is called a model. Learning takes place without effort; however, the observer must be paying attention. Reinforcement is not necessary for learning to take place; however, it does determine whether the behavior is imitated. Reinforcements and punishments can be vicarious; if the model’s behavior has a pleasurable outcome it is more likely to be repeated by the observer. The learner may receive reinforcements or punishments for imitating the model, this also affects behavior. Some models are more likely to be imitated than others

Watch Bandura’s Study Play Film Clip

Observational Learning Seems to be a powerful source of the socialization process through which children learn about which behaviors are, and are not, appropriate in their cultures.