Learning and Classical Conditioning Concepts

Learning

• Learning is defined as the process of acquiring new knowledge, skills, or behaviors.
• Learning involves understanding how new information is acquired and how existing knowledge is modified.
• Learning can be divided into various categories depending on what helps, and what hinders the process.
• A key aspect of learning is the role of associations, which will be discussed.

Pavlov's Unexpected Discovery

• Pavlov was studying digestion in dogs.
• He observed that dogs salivated in response to stimuli associated with food, even in the absence of food.
• This observation led to the discovery of classical conditioning.
• Learned associations between stimuli were found even when food was absent.
• Dogs responded to stimuli not only based on biological need, but as a result of learning.

Classical Conditioning

• A learning process where a neutral stimulus becomes associated with a stimulus naturally producing a response.
• Involves five primary components
  • Neutral Stimulus (NS): Initially does not elicit a particular response
  • Unconditioned Stimulus (UCS): Naturally triggers a response
  • Unconditioned Response (UCR): Natural response to UCS
  • Conditioned Stimulus (CS): Formerly neutral stimulus, now triggers a response after association
  • Conditioned Response (CR): Learned response to CS

The Basics of Classical Conditioning

• Neutral stimulus (NS): A stimulus that before conditioning does not naturally bring about a response of interest
• Unconditioned stimulus (UCS): A stimulus that naturally brings about a particular response without having been learned- Unconditioned response (UCR): A response that is natural and needs no training (e.g., salivation at the smell of food)
• Conditioned stimulus (CS): A neutral stimulus that has been paired with an unconditioned stimulus to bring about a response formerly caused only by the unconditioned stimulus.
• Conditioned Response (CR): A response that, after conditioning, follows a previously neutral stimulus.

Classical Conditioning Steps

• Neutral stimulus (NS) does not elicit a specific response
• Pair NS repeatedly with UCS, which elicits a UCR
• Eventually, the NS becomes a conditioned stimulus (CS), eliciting a conditioned response (CR)

The Basics of Classical Conditioning- Remember

• Conditioned = learned; unconditioned = not learned
• An unconditioned stimulus leads to an unconditioned response
• An unconditioned stimulus triggers the unconditioned response innately
• During conditioning, a previously neutral stimulus is transformed into the conditioned stimulus

The Basics of Classical Conditioning-Stimulus and Response

• Neutral stimulus & conditioned stimulus are the same stimulus after conditioning.
• Unconditioned response and conditioned response are the same response.
• The difference between the responses is what triggers them: the unconditioned response is triggered by the unconditioned stimulus whilst the conditioned response is triggered by the conditioned stimulus.

Unlearning?

• What if we want to unlearn something?
• What if there is an association between two things we do not want to continue?
• How do we break that association?

Extinction

• Occurs when a previously conditioned response decreases in frequency and eventually disappears.
• To produce extinction, one needs to break the association between the CS and UCS
• Extinction occurs when the conditioned stimulus is repeatedly presented without the subsequent unconditioned stimulus
• Example: The bell followed by no meat, repeatedly.

Stimulus Generalization and Discrimination

• After a conditioned stimulus elicits a response, similar stimuli will elicit a similar response
• The more similarity between stimuli, the more likely generalization will occur
• If a stimulus is very different, there will be no similar response—discrimination.
• Example: Pigeons learn that a green light signals food, whereas a red light signals no food.

Evaluative Conditioning

• Changing the liking of a stimulus by pairing it with other positive or negative stimuli.
• Pairing a neutral stimulus with a stimulus that triggers positive reactions leads to the neutral stimulus becoming a conditioned stimulus.

Conditioned Fears & Phobias

• Classical conditioning can lead to the development of fears and phobias
• Example: Watson's Little Albert experiment, where a white rat was paired with a loud noise, eliciting a fear response.

Conditioned Taste Aversions

• Develop aversions to foods followed by nausea or illness
• Example: Seligman's “sauce Bearnaise syndrome”
• Lengthy delay between food and illness—why only the sauce as a CS?
• Biological preparedness: organisms more readily learn certain associations.

Operant Conditioning

• Learning in which a voluntary response is strengthened or weakened depending on its consequences
• Unlike classical conditioning, behaviours are not automatic or involuntary responses.

Thorndike's Law of Effect

• Responses leading to satisfying consequences are more likely to be repeated
• Responses followed by negative outcomes are less likely to be repeated

The Basics of Operant Conditioning

• Thorndike's research influenced B. F. Skinner, who created the Skinner box.
• Thorndike's goal was to get cats to learn to obtain food by leaving the box; in the Skinner box animals learn to obtain food by operating on their environment within the box.
• Skinner became interested in specifying how behaviour varied as a result of alterations in the environment.

Reinforcement

• Process by which a stimulus strengthens the probability of a preceding behavior being repeated
• A reinforcer is any stimulus that increases the likelihood of a preceding behaviour occurring again.
• Primary reinforcer: satisfies biological needs (food, water, warmth)
• Secondary reinforcer: gains reinforcing properties through association with a primary reinforcer

Shaping

• Process of teaching a complex behavior by reinforcing closer and closer approximations of the desired behavior
• Start by reinforcing any behavior similar to the target
• Gradually reinforce only responses closer to the desired behavior
• Finally, reinforce only the desired behavior

Positive and Negative Reinforcers

• Positive reinforcer: stimulus added to the environment increasing a response
• Negative reinforcer: unpleasant stimulus removed increasing a response

Positive and Negative Punishment

• Punishment: stimulus decreasing the probability that a behavior will occur again
• Positive punishment: introducing an unpleasant stimulus
• Negative punishment: removing a pleasant stimulus

Schedules of Reinforcement

• Different patterns of frequency and timing of reinforcement
• Continuous reinforcement: reinforcing a behavior every time it occurs
• Partial reinforcement: reinforcing a behavior some but not all times

Schedules of Reinforcement (Two Main Categories)

• Fixed-ratio schedules
• Variable-ratio schedules
• Fixed-interval schedules
• Variable-interval schedules

Discrimination and Generalization

• Similar to classical conditioning, operant conditioning involves discrimination and generalization.
• Stimulus control training: process by which people learn to discriminate stimuli.
• Reinforcers follow responses based on the presence or absence of a stimulus.

Latent Learning

• Learning that is not apparent from behavior when it first occurs.
• Learning can occur without reinforcement.
• Example: Rats learning a maze without reinforcement, then performing well when reinforcement became available.

Observational Learning

• Learning by observing another person and watching whether they are rewarded or punished for their behavior
• Example: Observational learning in Bandura's famous Bobo Doll experiments.