PSYU2236 Aversive Control: Escape and Avoidance & Punishment PDF

10/22/24 Aversive control: Escape and Avoidance and Punishment PSYU2236/PSYX2236 Biopsychology & Learning Lecturer: Dr Gaurav Patil Original Slides: Dr Kim Curby 1 2 1 ...

10/22/24 Aversive control: Escape and Avoidance and Punishment PSYU2236/PSYX2236 Biopsychology & Learning Lecturer: Dr Gaurav Patil Original Slides: Dr Kim Curby 1 2 1  10/22/24 Procrastination: the discomfort we often feel when we start working on a difficult assignment serves as positive punishment, motivating escape behaviours that in turn result in negative reinforcement (removal of our discomfort) which in turn reinforces avoidance learning. 3 Today’s Lecture: Overview & Learning Objectives AVERSIVE CONTROL: ESCAPE AND AVOIDANCE Defining escape and avoidance and their relationship Learned helplessness Passive vs active avoidance Discriminative or signaled avoidance Theories of avoidance Two-factor theory One-factor theory Cognitive theory of avoidance 4 2  10/22/24 Behaviour Consequences: Escape & Avoidance Learning Reinforcement: Punishment: Increases the behaviour Decreases the behaviour that precedes it that precedes it Positive: Presentation of a Adding an aversive Adds something to the favourable outcome outcome Motivates Escape environment Negative: Removal of an aversive Removal of a desirable Removes something stimulus stimulus from the environment Reinforces Avoidance Learning 5 Escape / Avoidance Escape: getting away from an aversive stimulus in progress Escape behaviour results in the termination of an aversive stimulus. Avoidance: behaviour occurs before aversive stimulus preventing the delivery of it Negative contingency between response and aversive stimulus Results in an increase in operant responding (behaviour) that is maintained by negative reinforcement 6 3  10/22/24 Escape and Avoidance Escape Avoidance 7 7 Escape In presence of aversive stimulus Make a response Aversive event terminates Action is negatively reinforced 8 4  10/22/24 What if there is no escape? 9 Neurosis, Learned Helplessness Uncontrollable bad events Perceived lack of control Generalised helpless behaviour 10 5  10/22/24 But what if there is escape? Better still, you can anticipate the aversive event before it affects you and evade it? Avoidance Learning! 11 Avoidance Active avoidance Actively making a response to avoid event, e.g., running away! 12 6  10/22/24 Active avoidance In a typical avoidance experiment………. Rat is trained in a shuttle box with a hurdle in the middle. A tone is presented for 10 seconds à electric shock delivered through the floor of the cage. If the rat jumps over the hurdle while the shock is on, the shock is immediately terminated. If the rat jumps before the shock comes on, then the tone is turned off and the scheduled shock is cancelled. Thus, depending on when the rat jumps over the barrier, it can either escape from the shock once it is on or avoid it altogether. This procedure is called signalled avoidance because the experimenter provides a signal to indicate when the shock is imminent. 13 Discriminative Avoidance Stimulus signals onset of aversive US Escape With experience à Avoidance CS CS US US R R 14 7  10/22/24 Measuring avoidance learning Avoidance learning is measured in latency to respond to the signal Escape This subject avoided shock on the 9th trial and continued to do Avoidance so thereafter! 15 Can learn to use SD to avoid US Brogden, Lipman, and Culler (1938) Guinea pigs With escape CS = tone US = shock (stimulated running) Without escape UR = pain Classical conditioning group CR = running Classical conditioning group* CS followed by US Avoidance group CS à run à no US CS à don’t run à US * CC Gp – no opportunity to escape/avoid Avoidance group ran! 16 8  10/22/24 Avoidance Passive avoidance Learning NOT to make response in order to avoid the event, e.g., staying quiet to avoid conflict 17 Passive Avoidance Passive avoidance using shuttle-box procedure It is a form of operant conditioning where the person/animal must abstain from an act or reaction – which will otherwise à a negative outcome The animals learn to suppress their normal dark-seeking reflex because their entry into a dark chamber is paired with a foot shock. Learn to stay in bright side of box (avoid shock) 18 9  10/22/24 Obsessive Compulsive Disorder vs Phobia OCD typically involves an active avoidance response Phobic behaviour typically involves a passive avoidance response. Example: A person with OCD will clean frequently or compulsively check things A person with a phobia will avoid object of their fear (e.g. dogs, or select units that don’t involve giving a presentation). 19 Avoidance “Paradox” A response/behaviour is made before the aversive stimulus occurs Behaviour clearly increases, so is reinforced But what is taken away (or delivered) to reinforce it? Mowrer and Lamoreaux (1942) ― “Therefore, not getting something can hardly, in and of itself, qualify as rewarding.” p. 6 § Bit of a problem for behaviourists who need to be able to specify a stimulus! 20 10  10/22/24 The solution: Secondary negative reinforcement Warning signal/stimulus, via its association with the punishment, produces a fearful response (i.e., it becomes a CS) Avoidance response reduces the conditioned fear response so serves as a (secondary) negative reinforcer Not getting "punished" or "injured", is rewarding if punishment is expected, i.e., the subject is anxious or fearful, and if this expectation in some ways gets reduced! Mowrer, O.H. & Lamoreaux. R.R. (1942). Avoidance conditioning and signal duration: a study of secondary motivation and reward, Psychological monographs, 54, no. 5 ; whole no. 247 21 Theories of Avoidance Two Factor theory: classical and operant learning experiences are involved in avoidance learning One Factor theory: relies solely on operant conditioning 22 11  10/22/24 Mower’s Two Process Theory of Avoidance Explains avoidance learning in terms of two necessary processes: 1. First the subject learns to associate the warning stimulus with the aversive stimulus This is a classical conditioning process: The warning stimulus of the light is the CS, the aversive stimulus (shock) is the US CS (light) US Shock UR (fear) CR (fear) Mowrer, O.H. (1947). On the dual nature of learning: A reinterpretation of “conditioning” and “problem-solving”. Harvard Educational Review, 17, 102-150. 23 Two Process Theory of Avoidance AVERSIVE CONTROL: ESCAPE AND AVOIDANCE 2. Now the subject can be negatively reinforced during the warning stimulus; this is the second, operant conditioning process Removes R CS i.e. escape fear Strengthens Thus the two-process theory reduces avoidance learning to escape learning! The organism learns to escape from the CS and the fear it elicits. 24 12  10/22/24 Avoidance Conditioning & Phobias Phobia – Irrational fear of specific object or situation – Fear is disproportionate to real threat – Acquisition –classical conditioning Elevator(CS) : Feeling Trapped (US) àFear (UR) Elevator(CS) à Fear (CR) – Maintenance – Avoidance (negative reinforcement) Elevator (SD): Avoid Elevator (RR) à Reduced Fear (SR) 25 Support for Two Factor Theory Two-factor theory predicts that the avoidance responding will be learned only to the extent that the warning signal terminates when a response is made. Kamin (1957)--trained four groups of rats in a two-chamber avoidance apparatus Rats could avoid the shock (US) and terminate the warning signal (CS). Rats could avoid the shock, but the warning signal (CS) remained on. Rats received the shock but could terminate the warning signal (CS). Rats could neither avoid the shock nor terminate the warning signal (CS). 26 13  10/22/24 Support for Two Factor Theory AVERSIVE CONTROL: ESCAPE AND AVOIDANCE A significant amount of avoidance responding occurred in the first group only (response terminates the signal and enables animal to avoid shock) As predicted by two-factor theory, avoidance responding was poor in the group that was able to avoid shock but could not terminate the signal 27 Futher Support for Two Factor Theory We know that delaying the onset of reinforcement reduces the effectiveness of reward. … So it should be possible to reduce the level of reinforcement by introducing a delay between the avoidance response and termination of the feared stimulus. After the avoidance response, the CS was terminated: (1) immediately (2) 2.5 seconds after the response (3) 5 seconds after the response (4) or 10 seconds after the response 28 14  10/22/24 Further Support for Two Factor Theory As predicted, the animals in the zero-delay condition successfully avoided shock on over 80% of the trials. Animals in the 10-second delay condition avoided shock on fewer than 10% of the trials. Effectiveness of CS termination to support avoidance was decreased by increasing delay Results suggest that the source of reinforcement in avoidance conditioning was the reduction of fear generated by the termination of the CS More support for the two-factor theory! 29 Two factor theory and extinction of response If the aversive stimulus is the unconditioned stimulus in the avoidance conditioning paradigm, then whenever an anticipatory (avoidance) response occurs, the US does not occur Based on what we know about extinction, the non-occurrence of the US should lead to a decrease in the likelihood (extinction!) of the response 30 15  10/22/24 Evidence against Two Factor Theory Solomon, Kamin & Wynne (1953) Conditioned avoidance responding in dogs Light (CS) : Shock (UCS) à Fear (UR) Light (CS) à Fear (CR) (fear response elicited by the CS) Light (SD ) : Cross Barrier (R) à Reduced Fear (SR ) Shock then disconnected Dogs jump barrier for 100s of trials to avoid shock!!! But…(R) should extinguish because CS occurred without the US How can a response be maintained if it is followed by nothing happening? 31 The Fearlessness Problem AVERSIVE CONTROL: ESCAPE AND AVOIDANCE Fear and avoidance are not as firmly linked as the theory believes: According to the theory, fear provides the motive to perform the avoidance response Early in experiments a dog would exhibit various signs of fear (whining, urination, shaking) when the tone was presented BUT once the avoidance response is well learned subjects respond without apparent fear 32 16  10/22/24 Alternation of Behaviour (Yo-yo) AVERSIVE CONTROL: ESCAPE AND AVOIDANCE Two-Factor theorists came back with this scenario: Every successful avoidance puts CS on extinction With extinction, fear drops, so motivation to avoid decreases Resulting in more shocks, strengthening CR again and increasing avoidance response But… we don’t really see this…. 34 Sidman Free-Operant Avoidance Avoidance can be learned without a warning CS Shocks at random intervals Response gives safe time Extensive training, but rats learn avoidance (errors, high variability across subjects) 35 17  10/22/24 Evidence against Two Factor Theory AVERSIVE CONTROL: ESCAPE AND AVOIDANCE Herrnstein & Hineline (1966) Rats placed in Skinner box Electric shock delivered randomly (probability =.3 for every 2- second period that elapsed) Probability of shock reduced from.3 to.1 if lever pressed Rats could not avoid or escape shock…just reduce number of shocks received Most rats learned the task and kept lower rate of shock probability Problem for two-factor theory: avoidance learning in absence of CS! Avoidance learning can be explained by one factor – reduction in shock rate (operant conditioning!)! 36 One-factor Theory Avoidance is negatively reinforced by the lower rate of aversive stimulation to which it is associated Reduction of aversive stimulation accompanying avoidance maintains avoidance Which theory is correct??? That depends!!! Several processes seem to be involved in avoidance learning 37 18  10/22/24 Sidman Free-Operant Conditioning Modulated by CS Sidman Free-Operant – bit of a problem for Two Factor theory BUT….. Rescorla and LoLordo (1965) trained dogs using the Sidman avoidance procedure (no warning stimulus and shock is programmed to occur at fixed time intervals) In this study shocks were programmed to occur every 10 seconds but every time the dogs jumped over the hurdle in the shuttle box they ensured a shock-free period of 30 seconds By jumping at least once every 30 seconds the dogs therefore could ensure they would never receive a shock Rescorla, R.A., & LoLordo, V.M. (1965). Inhibition of avoidance behavior. Journal of Comparative and Physiological Psychology, 59, 406-412. 38 Rescorla, R.A., & LoLordo, V.M. (1965) AVERSIVE CONTROL: ESCAPE AND AVOIDANCE Once dogs learned the avoidance response, they were confined to one half of the shuttle box and given discriminative fear conditioning trials: one tone (CS+) was followed by shock and another tone (CS-) was not. Sidman avoidance training was resumed and once dogs were responding reliably, CS+ and CS- were occasionally presented for five seconds. When the CS+ was presented the rate of jumping doubled When the CS- was presented the rate of responding fell to almost zero 39 19  10/22/24 Rescorla & LoLordo (1965) AVERSIVE CONTROL: ESCAPE AND AVOIDANCE Rescorla & LoLordo: CS+ can amplify avoidance CS- can reduce avoidance Evidence that the conditioned stimuli have acquired drive properties Supports the Two Factor Theory’s position that it is the CS that drives the avoidance response! 40 Cognitive theory of avoidance learning Cognitivists believe avoidance responding is based not on fear but on the subjects’ expectation that a response will avoid shock: During initial training, when the warning stimulus is followed by shock, it is assumed that subjects form an expectation that shock will occur when the stimulus is presented When the animal eventually jumps over the barrier to avoid shock, a new expectation forms (shock does not occur if the response is made) So the next time the warning stimulus is presented, the animal recalls both expectations (shock occurs if it doesn’t jump but not if it does) and because it prefers not to be shocked it will perform the response that produces this outcome 42 20  10/22/24 Cognitive explanation of avoidance learning based on expectations Thus, fear has little role in this theory...it can therefore account for the shortcomings of two factor theory. First, regarding the disappearance of fear during training: Two factor theory assumes that once the avoidance response is learned and the warning stimulus is no longer followed by shock, the fear conditioned to this stimulus will extinguish But the animals continue to jump because it still expects shock to occur if it doesn’t jump, and prefers to avoid this outcome. 43 Cognitive explanation of avoidance learning AVERSIVE CONTROL: ESCAPE AND AVOIDANCE Second, regarding the difficulty of extinguishing avoidance behaviour this also follows directly from a cognitive analysis: The theory says that avoidance depends on two expectations: in the absence of a response shock will occur; BUT if the response is made shock will not occur Early in extinction, the dog holds both of these expectations and therefore responds. And when shock doesn’t occur its expectation that responding will not be followed by shock is confirmed and it therefore continues to jump With each new trial this expectation receives further confirmation, so if anything the tendency to jump should be strengthened 44 21  10/22/24 Response Prevention à extinction AVERSIVE CONTROL: ESCAPE AND AVOIDANCE If this analysis is right then animals continue to respond during extinction because they never get a chance to learn what would happen if they didn’t respond... Katzev and Berman (1974) trained rats to avoid shock in a shuttle box and then gave them 50 extinction trials during which the CS was still presented but shock no longer followed. Control Group: was still allowed to jump over the barrier during this phase to terminate CS Response prevention/flooding group: had a barrier placed above the hurdle so that they could not jump. Katzev, R.D., & Berman, J.S. (1974). Effect of exposure to conditioned stimulus and control of its termination in the extinction of avoidance behavior. Journal of Comparative and Physiological Psychology, 87, 347-353. 45 Katzev & Berman, 1974 AVERSIVE CONTROL: ESCAPE AND AVOIDANCE Rats that could control the termination of the conditioned stimulus (CS) showed faster extinction of avoidance behavior. Longer durations of CS exposure without the shock led to more rapid extinction of the avoidance behavior. The combination of longer CS exposure and the ability to control its termination was most effective in extinguishing avoidance behavior. In rats conditioned avoidance reduces more, the longer that response prevention continues. 46 22  10/22/24 Cognitive theory of avoidance AVERSIVE CONTROL: ESCAPE AND AVOIDANCE The fact that fear plays a minor role in this theory allows it to explain the continuation of avoidance responding in the absence of fear; but for the same reason it has difficulty explaining evidence that fear does influence avoidance... In the Rescorla and LoLordo experiment described earlier, for example, presenting a stimulus that had previously been paired with shock doubled subjects rate of responding (even though they were already avoiding shock effectively). 47 Summary AVERSIVE CONTROL LECTURE Positive punishment/aversive events motivate escape behaviours which are strengthened via negative reinforcement Avoidance learning involves avoiding the aversive event before it occurs Learned avoidance can take a passive or active form There are a number of theories of avoidance ― Two Factor theory § Classical and operant conditioning are involved in avoidance learning § Avoidance is driven by an escape from fear, not prevention of aversive event ― Cognitive theory of avoidance § Avoidance responding is based not on fear, but on the subjects’ expectation that a response will avoid an aversive stimulus 51 23  10/22/24 Break LOCATING THE SURVEYS 52 Locating the surveys 53 24  10/22/24 Your responses will be treated confidentially ! You cannot be identified in reports of survey responses. Survey results will only be released to teachers after grades are finalised. 54 Today’s Lecture: Overview & Learning Objectives AVERSIVE CONTROL LECTURE Types of negative punishment Intrinsic Vs. extrinsic punishment Primary Vs. Secondary punishers Limitations of the use of punishment Effective use of the use of punishment Theoretical accounts of how punishment works 56 25  10/22/24 Behaviour Consequences: Escape & Avoidance Learning Reinforcement: Punishment: Increases the behaviour Decreases the behaviour that precedes it that precedes it Positive: Presentation of a Adding an aversive Adds something to the favourable outcome outcome environment Negative: Removal of an aversive Removal of a desirable Removes something stimulus stimulus from the environment 57 Punishment definition AVERSIVE CONTROL LECTURE Punishment is the weakening of a behaviour through either the : 1. application of an aversive stimulus (positive punishment) or 2. removal of an appetitive stimulus (negative punishment). 58 26  10/22/24 Re-cap: Positive Punishment AVERSIVE CONTROL LECTURE Consists of the presentation of an aversive event following a response. This leads to a decrease in the future strength of that response. Examples: A child having to do the dishes for talking back to their parents A person being reprimanded by their boss for missing an important deadline 59 Re-cap: Negative Punishment AVERSIVE CONTROL LECTURE Consists of the removal of an appetitive event following a response. This then leads to a decrease in the future strength of that response. Examples: A loss of employment for being obnoxious A loss of money (fine) for overstaying parking time 60 27  10/22/24 Punishment AVERSIVE CONTROL LECTURE Bear in mind that the ‘to-be-punished’ behaviour is enjoyable to the individual doing the misdemeanour and they won’t want to stop! And what we have seen from extinction is that we cannot unlearn a behaviour – can only hope to suppress or inhibit it; or train individual to omit it. 61 Two types of negative punishment AVERSIVE CONTROL LECTURE 1. Time-out – Loss of access to positive reinforcers following problem behaviour (e.g., send child to room) 2. Response cost - aka Omission Training – Removal of reinforcer for inappropriate behaviour – The stimulus that is removed must decrease the frequency of the operant behaviour (by definition à punisher!) 62 28  10/22/24 Time-Out The loss of access to positive reinforcers for a brief period of time following the occurrence of a problem behaviour. Example: ― Punish a child’s misbehaviour by sending them to the bedroom or by making them sit in a corner for several minutes. It is likely to be ineffective: ― if the time-out setting is actually more reinforcing ― time-outs that are too long will interfere with the development of more appropriate behaviours 63 Time-Out AVERSIVE CONTROL LECTURE Time-out ineffective if the time-out setting is more reinforcing! 64 29  10/22/24 Response Cost AVERSIVE CONTROL LECTURE The removal of a valued reinforcer following the occurrence of a problem behaviour. The stimulus that is removed must decrease the frequency of the operant behaviour (by definition → punisher!) Aim: offender learns to omit the problematic behaviour Examples: Taking a child’s toys away for misbehaving Having to put money in a jar for swearing Speeding/parking ticket 65 Response Cost AVERSIVE CONTROL LECTURE It is easy to adjust the punishment to suit the ‘size’ of the problem behaviour. Time-out à suspension à expulsion School: Time-out → suspension → expulsion Speeding in school zone: 10km/h $389 20 km/h $632 30 km/h $1,224 fine (+ demerits) You must clearly identify a reinforcer that, if removed, will have an impact on targeted behaviour 66 30  10/22/24 Negative Punishment vs Extinction AVERSIVE CONTROL LECTURE Similarities - Both involve removal of reinforcers - Both result in decreasing strength of behaviour Differences - Extinction – behaviour that previously produced the reinforcer no longer does and behaviour stops (e.g., whining no longer produces lollypop) - Negative punishment – performing the behaviour results in loss of reinforcer that is already possessed (e.g., whining results in lollypop being taken away) 67 67 Negative Punishment vs Extinction AVERSIVE CONTROL LECTURE Does the behaviour grow weaker because performing it: no longer leads to something? …. then extinction! Or leads to the removal of something that you would otherwise possess? … then negative punishment! 68 31  10/22/24 Intrinsic vs extrinsic punishment AVERSIVE CONTROL LECTURE Intrinsic punishment – The behaviour being performed is inherently punishing (e.g., less likely to lift a heavy object if you experience pain last time object was lifted) Extrinsic punishment – The event that follows the behaviour is punishing (e.g., being chastised after posting inappropriate message on a discussion board) 69 Primary vs Secondary Punishers AVERSIVE CONTROL LECTURE Primary punishers – Events that are inherently / innately punishing e.g. pain, intense heat, loud noises, hunger pangs… Secondary (conditioned) punishers – an event that has become punishing because it has in the past been associated with some other punisher. E.g. CER paradigm Stage 1: Tone (CS) : Shock (UCS) → Fear (UCR) Tone (CS) → Fear (CR) Stage 2: Rat is in a Skinner box bar-pressing for food….. Tone (CS) sounds à rat stop responding 70 32  10/22/24 Secondary or Conditioned Punisher AVERSIVE CONTROL LECTURE Some human examples: E.g. An icy stare! … Or a speeding ticket! E.g., Greta Thunberg’s death stare directed at Donald Trump 71 Problems with the Use of Punishment AVERSIVE CONTROL LECTURE 1. Punishment of an inappropriate behaviour does not directly strengthen the occurrence of appropriate behaviour It may even result in a general suppression of behaviour - E.g. punishing swearing might i all verbal interactions 2. The person delivering the punishment could become a Discriminative Stimulus - SD - for punishment. The unwanted behaviour is suppressed only when that person is present 72 33  10/22/24 SD or Signal for Punishment AVERSIVE CONTROL LECTURE e.g. excessive speed is only curbed when speed cameras are present 73 73 Problems with the Use of Punishment (cont’d) AVERSIVE CONTROL LECTURE 3. Punishment might simply teach the individual to avoid the person who delivered the punishment, or choose a different route 4. Punishment is likely to elicit a strong emotional response. This might interfere with any subsequent attempts to teach appropriate behaviours Parking tickets – not well received! 74 34  10/22/24 Problems with the Use of Punishment (cont’d) AVERSIVE CONTROL LECTURE 5. Punishment can sometimes elicit an aggressive reaction. The aggression may be directed at the punisher or another target 6. The use of punishment might teach the person that punishment is an acceptable means of controlling behaviour Employee goes home and takes it out on their partner! 75 Problems with the Use of Punishment (cont’d) AVERSIVE CONTROL LECTURE 7. The use of punishment is often strongly reinforced The punisher may be enticed to punish more often because they like the results- i.e., the behaviour of punishing is reinforced so it is likely to continue and strengthen. However, when punishment doesn't work it can result in the punisher making the punishment more intense, frequent, or lasting, triggering an escalating spiral. 76 35  10/22/24 Benefits of Punishment AVERSIVE CONTROL LECTURE Góis et al. (2019) investigated the impact of reward and punishment in collective endeavours that require a minimum collective effort to ensure benefits. In such case, everyone shares the ensuing benefits and thereby individuals can free ride on the effort of others. e.g., strategic decisions by individuals to limit their emissions to mitigate climate change Rewards (positive incentives) were found to be essential to initiate cooperation, mostly when the perception of risk is low.....But sanctions (negative incentives) are instrumental to maintain cooperation. Best results are obtained when both rewards and sanctions (punishment) are synergistically combined into a single policy 77 Effective Use of Punishment AVERSIVE CONTROL LECTURE 1. Punishment should be immediate rather than delayed This aids the association between the punishment and the unwanted behaviour. 2. Punishment should be intense enough from the outset to suppress the target behaviour This can help avoid the use of very intense, abusive punishment. 3. Punishment should consistently follow each occurrence of the unwanted behaviour (Remember the behaviour is enjoyable to the perpetrator!) 80 36  10/22/24 Empty threat – punishment intensity too low! AVERSIVE CONTROL LECTURE Responding to a behaviour with a mild punishment often has little effect To modify future occurrences of the behaviour a more intense punishment is needed than would have been necessary at the outset 81 Other factors to keep in mind… AVERSIVE CONTROL LECTURE 4. Negative punishment is generally preferable to positive punishment. This is less likely to produce many of the harmful side effects of punishment. 5. Punishment is more effective when accompanied by an explanation. Thus, it easier to avoid punishment in the future. 6. Punishment of inappropriate behaviour should be combined with positive reinforcement for appropriate behaviour. E.g. Timeout for being naughty should be supported with praise for good behaviour 82 37  10/22/24 Punishment: Conditioned Suppression Account AVERSIVE CONTROL LECTURE Punishment does not directly weaken a behaviour, but instead produces an emotional response that interferes with the occurrence of the behaviour. Example: When the rat is shocked, it becomes too frightened to press the lever. - Lever response is omitted by default of their fear response i.e. it simply replaces the punished behaviour with an emotional response, or another behaviour, that interferes with being able to produce it. 83 Punishment: Conditioned Suppression Account AVERSIVE CONTROL LECTURE Skinner (1938) experiment: first trained 2 groups rats to bar-press on VI schedule (food) over 3 sessions. Extinction commenced in a 4th session – one group, in addition to extinction, during the first 10 mins on Day 1 the lever slapped their Effects of punishment paws. are temporary Result: Mild punishment initially reduced the number of responses; but the suppression was only temporary 84 38  10/22/24 Avoidance Account of Punishment AVERSIVE CONTROL LECTURE Again, punishment is not believed to directly weaken a behaviour. Punishment actually involves avoidance learning in which the avoidance response consists of any behaviour other than the behaviour being punished Become a better liar, criminal, learn where the speed cameras are. Another example of the permanency of original learning! 85 Summary AVERSIVE CONTROL LECTURE There are two main types of negative punishment Time-out Response cost Punishments can be intrinsic or extrinsic Punishers can be primary or secondary (conditioned) There are a number of important problems/limitations of punishment For punishment to be effective it needs to be administered immediately, consistently, and be of sufficient intensity to suppress the behaviour! There are a number of theoretical accounts of punishment Conditioned Suppression Account Avoidance Account 86 39