Learning Experiments and Concepts

What is learning?

Albert Bandura argued that individuals, especially children learn aggressive responses from observing others, either personally or through the media and environment.

There are four component processes influenced by the observer’s behavior following exposure to models.

These components include: attention; retention; motor reproduction; and motivation

PAVLOV’S DOG

He noted that dogs were not only responding to a biological need (hunger), but also a need developed by learning.

PAVLOV’S DOG

Even when Pavlov took away the meat powder, the dog continued to salivate at the sound of the tuning fork.

PRINCIPLES OF CLASSICAL CONDITIONINGIn classical conditioning, an organism learns to associate one stimulus with another. The organism learns that the first stimulus is a cue for the second stimulus. In Pavlov’s experiment above, the tuning fork cued the dogs that food might be coming. Following is an example of classical conditioning.

PAVLOV’S DOG

In technical terms, the food is an unconditioned stimulus (UCS) and the salivation is the unconditioned response (UCR). The bell is a neutral stimulus until the dog learns to associate the bell with food. Then the bell becomes a conditioned stimulus (CS) which produces the conditioned response (CR) of salivation after repeated pairings between the bell and food.

WATSON’S BABY ALBERTJohn B. Watson was interested in how classical conditioning could be applied to humans.

KEY CONCEPTS OF CLASSICAL CONDITIONING Unconditioned Stimulus (UCS)

A stimulus that elicits a response without conditioning

Unconditioned Response (UCR)Automatic response elicited by the unconditioned stimulus

Conditioned Stimulus (CS)A neutral stimulus that when paired with an unconditioned stimulus (UCS) elicits a similar response

Conditioned Response (CR)A response that is learned by pairing the originally neutral conditioned stimulus (CS) with theunconditioned stimulus (UCS)

Perhaps Psychology’s most famous Experiment

AcquisitionThe acquisition phase is the consistent parings of the CS (bell) and the UCS (food) that produces a CR (salivation). In the example above, this phase occurs when the dog begins to salivate at the sound of the bell. Conditioning occurs more rapidly when the food follows the bell by a half a second.

ExtinctionThe extinction phase is when the conditioned response no longer occurs after repeated pairings without the unconditioned stimulus. The dog’s response to the bell can be extinguished by repeatedly presenting the bell (CS) without the food (UCS). The dog has not completely forgotten the association between the bell and the food. If the experimenter waits a day, the dog may have a spontaneous recovery of the conditioned response and salivate again to the bell.

GeneralizationOccurs when there is a small difference in the presented stimulus and the original conditioned stimulus. If Pavlov’s dog heard a bell of a similar tone, the dog would still salivate.

DiscriminationThe opposite of generalization, discrimination happens when a conditioned response does not occur when there is a difference between the presented stimulus and the original conditioned stimulus. If Pavlov’s dog heard a bell with a different tone and was not awarded the unconditioned stimulus (food), the dog would learn not to salivate to the second tone.

SKINNER’S OPERANT CONDITIONINGBeginning in the 1930’s, Skinner started his experimentation on the behavior of animals. Skinner's quest was to observe the relationship between observable stimuli and response. Essentially, he wanted to know why these animals behaved the way that they do. Skinner controlled his experiments by using “Skinner boxes.”

PRINCIPLES OF OPERANT CONDITIONING

The main principles of operant conditioning, as defined by Skinner, are reinforcement, punishment, shaping, extinction, discrimination, and generalization.

KEY CONCEPTS OF OPERANT CONDITIONING Reinforcement

The process in which a behavior is strengthened, and thus, more likely to happen again.

Positive ReinforcementMaking a behavior stronger by following the behavior with a pleasant stimulus. For example, a rat presses a lever and receives food.

Negative ReinforcementMaking a behavior stronger by taking away a negative stimulus. For example, a rat presses a lever and turns off the electric shock

PunishmentThe process in which a behavior is weakened, and thus, less likely to happen again.

Negative Punishment Reducing a behavior by removing a pleasant stimulus when the behavior occurs. If the rat was previously given food for each lever press, but now receives food consistently when not pressing the lever (and not when it presses the lever), the rat will learn to stop pressing the lever.

Positive PunishmentReducing a behavior by presenting an unpleasant stimulus when the behavior occurs. If the rat previously pressed the lever and received food and now receives a shock, the rat will learn not to press the lever.

ShapingTechnique of reinforcement used to teach new behaviors. At the beginning, people/animals are reinforced for easy tasks, and then increasingly need to perform more difficult tasks in order to receive reinforcement. For example, originally the rat is given a food pellet for one lever press, but we gradually increase the number of times it needs to press to receive food, the rat will increase the number of presses.

ExtinctionThe elimination of the behavior by stopping reinforcement of the behavior. For example, a rat who received food when pressing a bar, receives food no longer, will gradually decrease the amount of lever presses until the rat eventually stops lever pressing.

Generalization In generalization, a behavior may be performed in more than one situation. For example, the rat who receives food by pressing one lever, may press a second lever in the cage in hopes that it will receive food.

DiscriminationLearning that a behavior will be rewarded in one situation, but not another. For example, the rat does not receive food from the second lever and realizes that by pressing the first lever only, he will receive food.