Operant Conditioning

Operant Conditioning

learning to operate on the environment to produce a consequence that influences future behavior. It involves reinforcement and punishment to shape behavior.

Skinner Box

B.F Skinner - used to control animal’s experience of reinforcement and punishment could be controlled. Includes food dispenser (reinforcer), lever that animals could press (target behaviour), coloured lights and speakers that signalled incoming food or shocks

Reinforcer

consequence of a behaviour that makes that behaviour more likely to recur in future

Positive Reinforcement

reinforcer added as rewarding consequence = behaviour more likely to reoccur - e.g. food released when lever is pressed

Negative Reinforcement

eliminating an aversive consequence = reproduce behaviour - e.g. pressing the lever stops electric shocks

Continuous Reinforcement

Reinforcement schedule where behaviour is reinforced every time it occurs = rapid extinction once reinforcer is withheld

Partial Reinforcement

Reinforcement schedule where behaviour is only reinforced some of the time = more persistent learning as becomes accustomed to reinforcement sometimes = greater resistance to extinction when reinforcement stops.

Extinction of a Reinforced Behavior

Occurs when reinforcement is withheld, leading to a decrease in the trained behavior

Shaping Behavior

Reinforces successive approximations to the desired behaviour (reinforcing small steps)

• start by reinforcing the initial behaviors that resemble the desired outcome

• drop reinforcement and wait for response closer to desired response = reintroduce reinforcement

• continue cycle until reach desired behaviour

Punisher

Any consequence of a behavior that makes that behaviour less likely to recur in the future = not as effective as reinforcement because it may only suppress behavior temporarily without teaching a more desirable alternative

Positive Punishment

aversive stimulus is presented as consequence of a behaviour e.g. in Skinner box electric shock

Negative Punishment (Response Cost)

when something desirable is removed as consequence of behaviour

Contingency

The relationship between the behavior and the punisher must be clear.

Contiguity

The punisher must follow the behavior swiftly.

Consistency

The punisher needs to occur for every occurrence of the behaviour = continuous schedule can’t be partial. This is because when undesirable behaviour goes unpunished learner experiences reinforcement and may continue the unwanted behavior.

Antecedent

A stimulus that occurs before a behavior, prompting the individual to respond in a certain way.

• ABC model of operant behaviour - Antecedent>Behaviour>consequence

Discriminative Stimuli

type of antecedent - signals availability of reinforcement for particular behaviour e.g. in Skinner box red light = impending shock, green light = food - based on classical CS-UCS association

reinforcement

A consequence that increases the likelihood of a behaviour being repeated. It can be positive, adding a desirable stimulus, or negative, removing an aversive stimulus.

types of reinforcement schedules

ratio (reinforced to non-reinforced behaviours) and interval (timing of reinforcers) - both can be either fixed or variable

fixed ratio schedule

delivers reinforcement after a specific number of responses - e.g. food after pressing lever 5 times

variable ratio schedule

delivers reinforcement after an average number of responses, unpredictable to the subject; creates a high rate of responding, e.g., gambling.

fixed interval schedule

delivers reinforcement after a specific amount of time has passed, provided at least one response has occurred; e.g., paycheck every two weeks = scallop shaped pattern of responding where behaviour increases before reward is due and drops off post-reinforcement

variable interval schedule

delivers reinforcement after varying amounts of time have passed, encouraging steady behavior, e.g., checking for a text message. = steady rate of responding more frequent than fixed interval

when is punishment effective

contingency, contiguity and consistency

drawbacks of punishment

positive punishment rarely leads to long-term behavior change and can create fear or resentment. Does not teach a more desirable behaviour