OPERANT CONDITIONING OPERANT CONDITIONING Operant Conditioning is the

OPERANT CONDITIONING

OPERANT CONDITIONING � � � Operant Conditioning is the same process as Instrumental Learning. Just a new name! An operant is a response that generates a consequence. Operant conditioning is based on Thorndike’s law of effect that an organism will tend to repeat a behaviour (operant) that has desirable consequences (such as receiving a treat), or that will enable it to avoid undesirable consequences (such as being given detention). Furthermore, organisms will tend not to repeat a behaviour that has undesirable consequences (such as disapproval or a fine).

Three-Phase Model of OC Stimulus (S) Response (R) (Always answered poorly on exams) Consequenc e (C)

Three-Phase Model of OC Sequence of events Terminology 1. Organism is placed in a situation 1. Stimulus 2. Organism produces a behaviour 2. Response 3. There is a consequence for this behaviour 3. Consequence: reinforcement or punishment 4. This consequence determines future behaviour 4. Behaviour continues or ceases

The Skinner Box

The Skinner Box

Skinner’s Experiments with Rats

Skinner’s Experiments with Rats � � � Skinner believed that all behaviour could be explained by the relationship between the behaviour, its antecedents (events that come before it) and its consequences. Skinner placed hungry rats in the Skinner Box and they scurried around the box randomly touching parts of the box. Eventually, the rat accidently pressed a lever. Immediately a pellet of rat food dropped into the food dish and the rat ate it. The rat’s random movements would eventually disappear and it was as fast at pressing the lever as it was at eating the pellet. The pellet was a reward for making the correct response. Skinner referred to different types of rewards as reinforcers.

Elements of Operant Conditioning Reinforcement Schedule of Reinforcement Types of Reinforcement Punishment

Reinforcement � � � Reinforcement is said to occur when a consequence (object or event) strengthens or increases the frequency or likelihood of a response that it follows. A reinforcer is any consequence (object or event) that strengthens or increases the frequency or likelihood of a response that it follows. Does reinforcer = reward? Not quite. . A reward implies something pleasurable, not something that strengthens a response.

Types of Reinforcement POSITIVE REINFORCEMENT � A positive reinforcer is a stimulus that strengthens or increases the frequency or likelihood of a desired response by providing a satisfying consequence. � $100 for every A+ NEGATIVE REINFORCEMENT � � A negative reinforcer is any unpleasant or aversive stimulus that, when removed or avoided, strengthens or increases the frequency or likelihood of a desired response. Not being grounded anymore because you cleaned your room

Drying Wet Hands. Thomas has wet hands after washing them. He rubs them in the towel and the water is now removed from them. He knows that every time he doesn’t want his hands to remain wet he can use a towel to get rid of the water. He now uses a towel every time he wants to remove the water from his hands. Why is this negative reinforcement? The water on his hands was present before he rubbed them in the towel. His behaviour of rubbing his hands in the towel removes the water and he uses a towel every time he wants this to happen. Therefore negative reinforcement is occurring. • Before (Stimulus): hands are wet. • Behaviour (Response): rub them in the towel. • After (Consequence): water is gone from his hands. • Future behaviour: Thomas will rub his hands when they are wet (strengthened)

Schedules of Reinforcement CONTINUOUS REINFORCEMENT � Initially, learning is most rapid if every correct response is followed by a reinforcer. PARTIAL REINFORCEMENT � However, once the behaviour is established, providing reinforcement for only some of the correct responses makes the behaviour much stronger.

Partial Reinforcement Schedules Fixed Ratio Variable Ratio Fixed Interval Variable Interval

Partial Reinforcement Schedules FIXED RATIO � � Reinforcement is given after a fixed number of responses have occurred. E. g. : You get paid money for every basket of fruit you pick or for every 10 dresses that you sew. VARIABLE RATIO � � You get reinforced after an unpredictable number (but constant mean number) of responses has occurred. E. g. : Gambling – pokies, Tattslotto etc

Partial Reinforcement Schedules FIXED INTERVAL � � Reinforcement is delivered after a fixed amount of time has elapsed. E. g. : Getting paid fortnightly VARIABLE INTERVAL � � Reinforcement is given for the first correct response after an irregular period of time has passed. E. g. : Fishing

Effectiveness of Schedules of Reinforcement

� � FIXED-RATIO: Quick, steady rate of response. However, the ratio needs to be a relatively frequent one in the acquisition phase of the learning process. VARIABLE-RATIO: Rapid, constant rate of response. This schedule is very effective in relation to the speed with which a response is acquired and the length of time taken for the response to cease. It seems that uncertainty about when the next reinforcement will occur actually keeps organisms responding steadily in the desired way, and extinction of the behaviour takes longer. FIXED-INTERVAL: Erratic, slow rate of response. Once the organism realises that time is the key factor, it stops responding for a while after the delivery of each reinforcer, but quickly responds as the time for next reinforcer approaches. VARIABLE-INTERVAL: Slow, steady rate of response. Reinforcement cannot be predicted. Weakening of a particular response under this schedule is gradual and much slower than under a fixed-interval schedule.

Punishment • Punishment is the delivery of an unpleasant consequence following a response. • Punishment has the same unpleasant quality as a negative reinforcer, but unlike a negative reinforcer, the punishment is given or applied, whereas the negative reinforcer is prevented or avoided. • When closely associated with a response, punishment weakens the response or decreases the probability of that response occurring again over time.

Types of Punishment PUNISHMENT � � � Punishment is the delivery of an unpleasant consequence following a response and thereby decreasing (or weakening) the likelihood of a response occurring again. A slap on the wrist for swearing Also known as ‘positive punishment’ RESPONSE COST � � Response Cost involves the removal of a (pleasant) stimulus and thereby decreasing (or weakening) the likelihood of a response occurring again. Common Room lost for messy behaviour Pocket money lost for swearing Also known as ‘negative punishment’

Reinforcement vs Punishment REINFORCEMENT � Strengthens behaviour PUNISHMENT � Weakens behaviour

Factors changing effectiveness or reinforcement and punishment Order of presentation Timing Appropriateness Pages 430 -431

Key Processes in OC Acquisition Extinction • Establishment of a response though reinforcement • Gradual weakening of a response due to nonreinforcement reappearance of a Spontaneous • The behaviour after Recovery apparent extinction.

Key Processes in OC • Occurs when a correct response is made to Stimulus something similar to Generalisation the original stimulus. • Occurs when a response does not Stimulus occur in the presence Discrimination of similar stimuli.

APPLICATIONS OF OPERANT CONDITIONING

Applications of OC Shaping Token Economies

Shaping � � � Shaping is a procedure in which a reinforcer is given for any response that successively approximates and ultimately leads to the final desired response, or target behaviour. Also called method of successive approximations – steps along the way to the desired behaviour are reinforced until the desired behaviour is shown. This process is routinely used in animal training.

Token Economy � � A token economy is a setting in which an individual receives tokens (reinforcers) for desired behaviour and these tokens can then be collected and exchanged for other reinforcers in the form of actual, or ‘real’, rewards. To be effective. . . � The desired behaviour and the token reward must be clear. � The rewards in exchange for tokens needs to be made clear. � Opportunities to “cash in” the tokens must be given.

Comparison of OC and CC Similarities � � � Both processes have an acquisition phase, extinction, stimulus generalisation, stimulus discrimination and spontaneous recovery. In CC we make an association between a neutral stimulus and unconditioned stimulus. In OC we make an association between the behaviour, the stimulus that caused it and the consequence that follows. CC and OC often happen at the same time. . . Little Albert was CC’ed to fear rats, but was OC’ed to move away from them

Comparison of OC and CC Differences � � In CC the response is involuntary, OC involves voluntary and involuntary responses. In CC the learner is a passive participant and the response is an automatic one. In OC the learner is an active participant and must demonstrate a behaviour before any consequence is given. In CC, the reinforcer is given BEFORE the behaviour. . . Food is given before salivation. In OC, the reinforcer is given AFTER the behaviour. In CC, the response is a reflexive behaviour. In OC the response is a conscious, voluntary one.

REVISION � � � � 11. 11 11. 12 11. 13 11. 14 11. 15 11. 16 11. 17 11. 18 11. 19 11. 20 11. 21 11. 23 11. 24 11. 25 Brain Teaser #19: ‘How do consequences influence future behaviour? ’ Discuss with reference to examples and research. Brain Teaser #20: ‘Classical Conditioning involves a passive participant and an automatic and involuntary response’. Discuss what is meant by this statement with the use of research and examples and explain how this differs with Operant Conditioning. Brain Teaser #21: Compare acquisition, extinction, spontaneous recovery, stimulus discrimination and stimulus generalisation in Classical Conditioning and Operant Conditioning.