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Punishment Definitions? • Learning from the consequences that produce pain or discomfort • The loss of reinforcers: This has survival value for the individual and for the species. • Punishment teaches us not to repeat responses that cause us harm • Any stimulus or event, when used contingently, decreases the probability of a response. Nature of Punishment • Punishment is defined neither by – the actions of the person delivering the consequences – nor by the nature of those consequences. • A decrease in the future frequency of the occurrence of the behavior must be observed before a consequence qualifies as punishment. Definitions of Punishment • Positive or Type I Punishment : – Presentation of a stimulus (or an increase in the intensity of an already present stimulus) immediately following a behavior – results in a decrease in the frequency of the behavior. – Spanking, electric shock, etc. • Negative or Type II Punishment: – termination of an already present stimulus (or a decrease in the intensity of an already present stimulus) immediately following a behavior – results in a decrease in the future frequency of the behavior. – Response cost, overcorrection Discriminative Effects • Stimulus condition in the presence of which a response has a lower probability of occurrence than it does in its absence • Response-contingent punishment: – Delivery occurs in the presence of a stimulus cue – Punishment only occurs when emitting contingent response. • Stimulus control is important: – If punishment occurs only in some stimulus conditions and not in others: the suppressive effects of punishment will be most prevalent under those conditions – Organism learns the setting conditions as to when punishment will occur – E.g.: Teacher has to see you misbehave Punishment is also Known as Aversive Control • Note that aversive events are associated with both: – positive punishment – negative reinforcement • Term aversive control is often used to describe intervention involving either or both of these two principles. Aversive but not contingent? • Aversive stimuli can also affect operant behavior when given noncontingently – That is, a targeted behavior neither produces nor prevents the punisher – when aversive stimuli occur independently of responding. • Most famous example is conditioned emotional response (CER) Conditioned Emotional Response (CER) • Basic set up: – Rat must lever press to obtain food. – Rat receives periodic pairings of tone with electric shock. (tone signals the shock) – Rat eventually press lever at a lower rate when tone is on than when it is off. • Phenomenon is called conditioned suppression or conditioned emotional response (CER; Estes & Skinner, 1941). Why are CER’s important? • The “threat” of an upcoming aversive event can decrease responding – Even when noncontingent – Unpredictability produces GREAT CERs • Because the aversive event is likely, organism “prepares” or “gets ready” for the event – Can be cued or uncued – Really gets in the way of ongoing responses • E.g., in dog training: if dog is afraid of being punished – Rate of overall responding goes down – Animal is afraid of punisher, so doesn’t ‘risk’ behaving Parameters of Punishment • Is all we learned about positive reinforcement true, in mirror-image form, of punishment? – Yes and no. – Are some additional characteristics of punishment • Any operant punishment situation is really a punishment plus reinforcement situation. – Just like any reinforcement situation =Sr + P – If get punished, don’t get the reinforcer. – If get the reinforcer, don’t get punished. Punishment + Reinforcement? • For punishment to suppress operant responding, responses must already be occurring with some frequency. • For responses to occur, they must be producing reinforcement. • So, effect of punishment reflects interaction of two contingencies--reinforcement and punishment. • Jointly operate in most situations. Punishment Effectiveness • Punishing only reinforced response is often not an effective procedure. – Suppresses responses – Doesn’t provide a “replacement” response • If you give organism an alternative, unpunished route to reinforcement, then effects of punishment are enhanced. • Always shape an incompatible response! – A response that is the opposite of the inappropriate response – E.g., punish getting out of seat but reinforce sitting in seat Punishment Intensity: • As intensity of punishing stimulus increases, degree of suppression increases. • If very intense shock is used, then suppression may be virtually complete. • Partially due to physiological effects; partially due to contingency effects Role of past experience! • Experience with the punisher is important – If never experienced shock, don’t know it hurts! – Punishment effects are relative: What has been prior experience and how is the punisher COMPARED to previous punishers? • Lots of research showing this: – Suppressive effect of intermediate shock intensity depends on animal’s past experience with shock. – If animal has experienced intensities going from mild to intermediate, then there will be little suppression. – If animal has experienced intensities going from severe to intermediate, then there will be substantial suppression. Immediate is Best! • For punishment to be maximally effective, it must immediately follow operant response. • As delay interval between response and punishment increases, amount of suppression decreases. • Too many other behaviors can occur between R and P; contingency not as effective when initially using P Probability of a punisher • Initially: should be certain and follow each operant response. – Probability of punishment should be 1.0 – When responses are punished intermittently, effectiveness of punishment procedure is reduced. • Can shape towards partial schedule of punishment • Is this different than what observe with reinforcement? Think about it! Recovery from Punishment: Extinction • When punishment is discontinued, suppressive effects on responding ARE not permanent • The rate of responding after punishment is discontinued will – not only recover – But briefly exceed level at which it was occurring prior to punishment – Opposite of extinction burst – Is this really surprising? Unconditioned Punishers • Unconditioned punisher: stimulus whose presentation functions as punishment without having been paired with any other punishers. – Innate – Biologically relevant – Still, all organisms not respond the same! • Unconditioned punishers will suppress any behavior that precedes their onset. • Again, is this similar to reinforcement? How are Conditioned Punishers different? • Conditioned punisher is a stimulus that functions as punishment as a result of a person’s conditioning history. – E.g., the word “no” is a conditioned stimulus – A child’s name can become a punisher!!!! • Acquires capability to function as punisher through stimulus-stimulus pairing with one or more unconditioned or conditioned punishers. Extinction of Conditioned Punishers • If responses occur in absence of punisher, the response will return, potentially to prepunishment levels • If the conditioned punisher is repeatedly presented without the punisher with which it was initially paired, effectiveness as punishment will diminish until it is no longer a punisher. Generalization and Discrimination • Stimulus that has been paired with numerous forms of unconditioned and conditioned punishers becomes a generalized conditioned punisher. • Stimulus that has been paired with only one specific conditioned or unconditioned punisher becomes a discriminated punisher. Other factors influencing effectiveness of punishment: • Schedule or frequency of punishment – Continuous punishment schedules knock down behavior more quickly – Partial punishment schedules keep behavior suppressed more effectively • Availability of reinforcement for the target behavior – Must eliminate inadvertent sources of reinforcement for your behavior targeted for punishment – Teacher may punish, but the other kids may keep reinforcing “class clown” behavior • Availability of reinforcement for an alternative behavior. – Punishment more effective if reinforce the opposite behavior – Again, must give organism alternative path to the reinforcer that was maintaining the unwanted behavior Punishment can lead to Aggression • Reflexive aggression: – When punished, act out aggressively – Is called reflexive because appears to be innate – When in pain, you bite! • Operant Aggression – Learn to be aggressive contingently – retaliatory Punishment and Aggression • Aggression may model aggression – That is, aggression breeds aggression – Use of aggression as punishment may provide model of how to “solve problems” • Social Disruption – The person who delivers the punishment/situation in which punishment occurs become tainted – Poisoning cues – Also called social disruption: • Behavior is disrupted in presence of cues that predict punishment • May get freezing, reduced effort, etc., in presence of punisher Is Time Out a Punisher? • Yes, by definition it is a negative punisher – Losing the opportunity to get reinforcement from many other sources – Again, to be effective, must really isolate so can’t get reinforced. • Time out is not isolation – Time out is brief, focused and contingent – Isolation is of long duration, often noncontingent, and often not effective. Rules for Using Time-Out • 1 minute per year of age – Not really effective for children under 6-9 mos – For really little ones, VERY brief withdrawal of attention • Must be quiet to get the timer to start • Cannot use for dangerous, disruptive or selfstimulatory behavior • Must really be “time out” from other rewards Negative Punishment • Response cost: your response costs you something or some behavior • OVERCORRECTION: two parts – Restitution: reinstatement of environment (clean up) – Positive practice: practice better response for situation – Can also use satiation/habituation Guidelines for using positive punishment • Behavior must be (immediately) dangerous to person or others • Rate of responding is so high that there is NO chance to interrupt and reinforce “good” behavior • Must have tried other alternatives • An example: http://www.youtube.com/watch?v=13UcT1FVVts Examples: • Severe self injurious behavior (SIB) • Highly aggressive behavior to others • Behavior which creates in immediate danger for self or others – Running into the street – Pulling a hot pan off the stove