Basic Forms of Learning

n Learning – a relatively enduring change in behavior as a result of previous experience

n The most basic forms of learning occur automatically, subconsciously – without any particular effort on our part.

n 2 forms of basic learning or “conditioning” involve learning associations between environmental events or stimuli and our behavioral responses.

Classical Conditioning

n We automatically learn what stimuli are usually associated with situations that demand a reflexive bodily response. Those stimuli come to trigger the body’s response.

n Classical conditioning is useful because learning to predict what’s coming allows the body to get ready ahead of time.

Ivan Pavlov

Pavlov’s Lab Setup

Evidence of Learning

n After repeated pairings, Bell Ringing (on its own) produced salivation.

n That response (e.g. salivating when you hear a bell ring) would never occur if learning had not taken place. It is a “conditioned (learned) response” (CR).

Acquisition, Extinction & Recovery

Example: Emotional & Sexaul Responses

Remember:

n Classical conditioning always begins with a stimulus (UCS) that triggers an unavoidable reflexive response of the body (UCR)

n Other neutral stimuli that regularly precede or accompany the UCS register in memory.

n Then those stimuli become CS for a learned response (CR) similar to original UCR.

n Classical conditioning is not just about drooling dogs – it’s the basis for all sorts of learned (conditioned) emotional responses as well. Our body has many natural emotional reflexes.

John B. Watson

n And the tale of Little Albert

Learning to Associate:

n Stimuli that occur just before a reflex (“classical conditioning” or “Pavlovian conditioning”)

Classical Conditioning of Bees

n Presenting a smell with sucroseàlearned extension of proboscis to smell alone

Classical Conditioning of Worms

n Presenting neutral smell along with noxious chemical à learned retraction

Learning to Associate:

n Stimuli that occur just before a reflex (“classical conditioning” or “Pavlovian conditioning”)

n Behavior with the consequences that follow that behavior

n Edward Thorndike-first to call attention to the importance of consequences, but then B.F. Skinner spent years revealing the principles of “operant conditioning”

Operant Conditioning

n Skinner Box or Operant Chamber

2 Types of Consequences:

n Reinforcement: a consequence that increases the likelihood of the behavior it follows

n Punishment: a consequence that decreases the likelihood of the behavior it follows

Positive Reinforcement

Modifying Behavior of Animals

Inadvertent Reinforcement

Learning Terms

n Same terms we encountered with classical conditioning can be applied to the operant conditioning situation:

n Acquisition (behavior which is reinforced gradually increases because of learning)

n Generalization (behavior reinforced in one situation may be shown in other situations)

n Extinction – disappearance of the behavior if we fail to reinforce it for too long

n Spontaneous Recovery- return of a previously extinguished response

2 Kinds of Reinforcement

n In addition to there being different types of consequences (+ rf, - rf, + pun, - pun), there are different contingencies for presenting the consequence – that is, what are the requirements before the consequence is delivered?

One Possibility:
Continuous Reinforcement

n Every correct response is followed by the reinforcing consequence

Partial or Intermittent Reinforcement

n Every correct response is NOT followed by the reinforcing consequence; reinforcement occurs only some of the time, according to some “schedule” or “contingency”

n Different schedules of reinforcement generate different patterns of behavior.

n Behaviors reinforced on a schedule of partial reinforcement are more resistant to extinction.

Common Schedules of Rf

n Skinner did not focus on consequences alone. He pointed out we also learn what situational stimuli typically indicate when certain consequences are likely.

Stimuli in Operant Situations

n Although stimuli do not automatically “trigger” operant responses the way an UCSàUCR, stimuli that are part of the situation in which a behavior has been reinforced are learned. These stimuli allow us to predict when reinforcement may be available.

n These are “discriminative stimuli” or the “antecedents” that set the stage for the operant behavior.

Cognitive Learning

n Learning based on observation and mental processing of what we’ve observed

n Does not require reinforcement

n Does not always require direct experience

3 Examples

n Edward Tolman – “latent” learning of a cognitive map

n Albert Bandura- observational learning, modeling, vicarious conditioning or “social learning”

n Wolfgang Kohler – insight learning in chimps