Operant Conditioning

What is it?Learning from the consequences of

behavior Depending on the consequences the

learner will learn to repeat or eliminate the behavior

Law of Effect

Responses are selected if they are followed by positive consequences.

Thorndike argued this was similar to a process of natural selection.

B.F. Skinner

ReinforcementStimulus/event that affects the

likelihood that a preceding behavior will be repeated

Skinner used shaping - reinforcers to guide an animal’s action toward a desired behavior. Immediate reinforcement is best.

Dolphins working for the military?

Positive v. Negative Reinforcement

Adding something good as a consequence

Examples: chimps and food; person working hard for a bonus

Removing something negative

Examples: students who complain about grades receive higher grade; daydreaming during a boring lecture

2 types (escaping something bad, or avoiding it)

Aversive Conditioning

Punishment - Adding something negative

Where reinforcement increases behavior, punishment will decrease a behavior. But: fails to provide an

alternative and has potentially negative by-products

Other PrinciplesFeedback:Essential to learning is that you need to

find out the response/results to your actionReinforcement is a type of feedback from

your actionsExtinction: Forget the learning if there is no longer a

response – it is distinct from punishment.

Contingency of Reinforcement

A description of the relationship between a response and a reinforcerExample of scolding a child for undesired

behavior, but the behavior remains…what’s happening?

Omission – reduce the probability of a response by giving positive reinforcement when the behavior does not occur…keep it REAL!

SHAPINGBehaviorists view reinforcement as the

underlying principle of all behavior – but how do we explain complex behavior?Baby steps

Skinner argued that new behavior came from random “behavioral drift.” Desired behaviors are developed through shaping.

Shaping – guiding acquisition of a response by providing successive reinforcement.

Reinforcement Schedules

Continuous Reinforcement - desired response is reinforced everytime it occurs.

Partial (intermittent) Reinforcement Fixed Ratio/Interval -

reinforce after a set number of responses/set amount of time.

Variable Ratio/Interval - reinforcement at unpredictable response numbers/unpredictable amount of time

Discriminative Stimuli – being able to determine which specific stimulus will bring a consequence.

Non-contingent Reinforcement – when a reinforcer is not related to a response.Consequences that

seem to come from random events.

We develop responses to these reinforcers - superstitious

Issues with Punishment

Depends on contiguity – need to be sure that the consequence is associated with the undesired behavior.

Avoidance – are you changing the behavior, or learning to avoid the consequence?Escape and Avoidance learning – learn new

behaviors to avoid something negative...how does this complicate behaviorism?

Other IssuesBiofeedback – Autonomic conditioningBiological constraints on learning

Critical Periods and PreparednessLorenz and the ducksGarcia et al. and “bait shyness” – essentially

taste aversion

So why does any of this matter?

Animal training Child raising

Reinforce good behavior.

Ignore whining. No harsh

punishment, explain misbehavior.

Or YOU…. (token economies)

LEARNED HELPLESSNESS

What if you keep trying to do something and just can’t get it?

What if the reinforcement just doesn’t matter that much to you?

Would you just give up?

Behavioral Neuroscience

Combining the behaviorist and biological perspectives.Learning is a process that involves

changes in neural activity.

Neural Plasticity – ability of the neural system to change in response to experience

Non-Associative LearningHabituation -

behavioral response that decreases over successive presentations of the stimulus.

Sensitization – behavioral response increases during presentations of the stimulus.

Associative LearningEye Blink

Learning resides in the cerebellum

Cerebellum normally inhibits the eye blink, but is conditioned to “synaptically” not respond.

FearLearning resides

in the amygdala.Long Term

Potentiation – persistent increase in synaptic transmission

Long Term Potentiation

Increased ability of a neuron to receive a message.Involves activity

of NMDA receptors on neurons.

Social Learning Theory

Social Learning Theory – focuses on learning within a social context, that people learn from one another. Includes the concepts of observational learning, imitation, and modeling.

An observer sees a model – and repeats

the behavior of the model.

General Principles:People learn by observing behavior of others, and the outcomes of that behavior.Learning can occur without a change in behavior – just through observation.Cognition (thinking) plays a role in learning. Awareness of events and future thinking determine what we learn.Social Learning is a bridge between behavioral learning and cognitive learning.

Role of the Environment in Reinforcing Learning:

Observer can be reinforced by the model.Observer reinforced by 3rd person.Imitated behavior leads to reinforcing

consequences.Consequences of the model’s behavior

affect the observer’s behavior vicariously.