Psych 1x03 final review PDF

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Classical conditioning ● ●

Conscious learning - student in the classroom, reading books Unconscious reflex learning - child only needs to touch a hot stove once to learn to avoid red hot objects ○ Vital to survival of species ○ More basic than conscious learning ● Case study ○ Nicole suffers chronic pain from low atmospheric pressure. The pain from her headaches usually coincides with the first few drops of rain falling to the ground. Recently, Nicole has noticed that her head begins to throb at the mere sight of a cloudy sky. To alleviate the pain, her doctor has prescribed her a medication, which comes in the form of a red pill. The side effects of ingesting the red pill are sweaty palms and some nausea. Classical conditioning ● Allows to relate two associate two related events ● Learning of contingency between a particular signal and a later event that are paired in time and or space ● Classical condition studied by Ivan Pavlov ○ Noticed that dogs would salivate before the food had reached the mouth ○ Would sound metronome before food being delivered to dogs ○ Before training, the sound would not affect the dog ○ After training, the dog would salivate - condition reflex ● He was studying contingent relationships ○ The presentation of one stimulus leads to the presentation of another ○ E.g. flash of lightning before the thunder ○ When an organism learns the association between a signal and an event, known as contingent relationships ● E.g. think of lemons, the mouth may start to salivate ○ The body getting ready to neutralizing citric acid from the lemon, prepare for digestion ○ Learned from previous times of eating a lemon Components of classical conditioning ● Unconditional stimulus (US) ○ Any stimulus or event ○ Occurs naturally, before learning ○ E.g. food placed in the dog’s mouth would make the dog salivate. The US would be placing food in the dog’s mouth ● Unconditional response (UR) ○ When the US occurs, UR always follows without the need for any training ○ Occurs naturally, prior to learning ○ Often biologically programmed reflex ○ E.g. food placed in the dog’s mouth would make the dog salivate. The UR would be salvation

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Conditional stimulus (CS) ○ A previously neutral stimulus that becomes associated with an unconditional stimulus ■ CS paired with US ○ Eventually triggers an event on its own ○ E.g. Sound of metronome paired with food being placed in dog’s mouth ○ Conditional stimulus always placed before the unconditional stimulus ■ To form a contingent relationship between CS and US ○ CS typically appears before US ■ May take several trials ■ When this happens, contingency forms ● Conditioned response (CR) ○ The response that occurs once contingency between CS and US are learned ○ Very similar to UR ○ E.g. sound of metronome eventually elicit a conditional response of salvation ● Acquisition ○ The process by which contingency between CS and US is learned ○ Shown as negatively accelerated increasing function ■ Most learning happens during early trails ■ There is some additional learning in every trail after, but never as much as early trials Contingencies acquired in one trial ● Rats developed special learning mechanisms for food selection ○ Often avoid unfamiliar food (dietary neophobia) ● They will eat small quantities of food at a time to pinpoint specific food that leads to sickness ○ Can learn this contingency in a single trial Does response require any prior learning ● If not, then is it unconditioned ● If it is, then it is conditioned Triggering event or its outcome ● If it is an event, then it is a stimulus ● If it is an outcome, then it is the response As long as conditional stimulus continues to be a reliable cue for unconditioned stimulus, continency will remain If conditions change so that the CS is a no longer a reliable cue, continency will fade Extinction ● Loss of CR when Cs no longer predicts the US ● CR made to fade through the process fo extinction ○ Presenting CS alone, repeatedly over many trials, without the US ○ At first, CS will elicit a conditional response ○ Over several trials, the response will become weaker and weaker

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Extinction is learning to inhibit the CS ○ Two processes that sit side by side ■ Original learned response to CS ■ New inhibitory learned response to the CS ● Spontaneous recovery ○ Sudden recovery of CR following a rest period after extinction ○ This phenomenon suggests extinction involves a new inhibitory learned response ■ Following the extinction procedure, the conditional-response fades ■ Following a rest period, if CS is presented again, it elicits CR ■ This suggests that the original relationship between CS and US was not unlearned ■ Extinction promotes a learned inhibitory response that competes with original contingency Stimulus generalization ● The process by which stimuli similar to the CS will also elicit CR ○ E.g. a child was bitten by a black Doberman ■ Black Doberman elicit fear ■ So does the sight of other dogs ● The strongest conditional response is elicited by the original CS ○ Similar CS also elicit a response at similar levels ■ Not as strong as original CS ● Stimulus generalization adds flexibility and efficiency to classical conditioning ○ If the stimulus is potentially dangerous, there is no need to require separate conditioning ○ Generalize learning to avoid similar stimuli ● After extinction, the generalization gradient should be flattened Stimulus discrimination ● Restricts the range of CS that elicit a response ○ Different stimulus similar to the original CS is shown without the UR ○ That conditioned response that is usually associated with this stimulus will diminish ■ However, the rest of the stimuli along the gradient remains intact ● CS+ predicts the presence of the unconditional stimulus (original stimuli) CS+ paired with the original US ● CS- predicts the absence of the unconditional stimulus (similar stimuli) CS- paired with the absence of original US ● If Cs+ and CS- are presented at the same time (following training) ○ The participant will show an intermediate response ○ Somewhere between the responses elicited by the two cues ● Generalization provides efficiency and flexibility, discrimination refines the learning process ○ Allows organisms to build complex responses Implosive therapy ● The individual is encouraged to confront the CS that evokes their anxiety

● CS is presented in absence of associated US ● Can be a traumatic experience Systematic desensitization ● Gradual exposure to the feared stimulus ● With generalization gradient ○ Start with extinguishing stimuli at the far end of the curve, working to the middle Homeostasis ● The body actively working to keep body processes within strict parameters ○ E.g. after drinking a sugary beverage. Internal blood glucose levels will surge. Insulin released to take up excess glucose to be stored ■ Blood glucose levels can be regulated, homeostasis maintained ● Compensatory response ○ The response that counteracts or compensates for changes in the body ○ E.g. US is ingestion of sugar, raises blood glucose ■ Naturally elicits insulin release to counter - UR ■ The taste of cola acts as CS which predicts a spike in blood glucose ■ Eventually, flavour cues will elicit CR of insulin release ● Classical conditioning allows the body to prepare for challenges to homeostasis Drug administration ● Chemical changes associated with drug administration also signalled by cues ● E.g. Morphine effects include decreased respiration and decreased pain sensitivity ○ Naturally-occurring effects of drugs are the US ○ The body responds with compensatory mechanisms that counteract drug effects, when morphine is taken, the body counters with UR so increased respiration and increased pain sensitivity ○ CS of the environment become paired with drug effect (US), contingency is learned ■ CS includes cues of the location ■ Paraphernalia ○ Environmental cues can trigger CR - compensatory responses which prepare the body for the drug effects

Instrumental Learning ● ●

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Involves explicit training between voluntary behaviours and their consequences Specific behaviour leads to a specific consequence ○ Hot stove - being burned ○ Mess with bulls - hurt by horns Instrumental conditioning is learning a contingency between behaviour and a consequence Psychologist Edward Thorndike ○ Investigating by studying cats in a puzzle box ○ Focus on overt behaviour rather than on mental elements or conscious experiences ○ A puzzle box could be opened by performing a specific behaviour (pulling a rope)

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Outside was a dish of food that provided motivation The prediction that Thorndike made was ■ At first, the cat would engage in random behaviour to try to escape ■ Eventually, come across a method to get out by accident ■ The cat would then escape immediately when placed in the same box ■ This did not happen ○ Cat learned from trial and error, rather than conscious learning of escape behaviour ■ Over several trials, random behaviours that did not lead to escape would occur less frequently ● A decrease in the frequency of random behaviours ■ Suggested that animals followed a simple stimulus-response type process ● No aha moment ○ Hypothesized a process called “Stamping in” and “Stamping out” ■ Behaviours that followed by a favourable consequence is stamping in ● Rope pulling ■ Random behaviours that did not lead to a favourable consequence is stamping out ● Turning in a circle ■ Leads to refinement ● Cats learn the contingency between specific behaviour of rope pulling and the consequence of food reward ● Law of Effect ○ Behaviours that produce a positive/pleasant consequence are stamped in ■ performed more frequently ○ Behaviours that produce a negative/unpleasant consequence are stamped out ■ performed less frequently ● The key difference between instrumental and classical conditioning ○ Instrumental is considering overt behaviours that are operated by an actor ■ Also referred to operant conditioning Four consequences (4 types of instrumental conditioning) ● Difficult to define satisfying or annoying states which determine the frequency of a behaviour ● Refer to the reinforcer, any stimulus ○ When presented after a response, leads to a change in the rate of that response ○ Responses are changed by positive and negative reinforcers 4 different types ● Reward training - presentation of a positive reinforcer following a response ○ Increase the frequency of the behaviour ○ E.g. presenting puppy every time he sits on command ● Punishment training - presentation of a negative reinforcer following a response ○ A decrease in the behaviour being reinforced ○ E.g. putting money in a vending machine is followed by an electric shock, the behaviour would decrease quickly

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Must consider the ethics of experiencing fear or pain in the recipient ■ When punishment used, the authority figure may, through classical conditioning, become a signal for pain, contingency formed ● Omission training - removal of a positive reinforcer following response ○ Discourages a behaviour ○ Removing a positive reinforcer is a situation that person would avoid ○ E.g. Child watching TV and teasing the sister ■ The mother wants to eliminate the teasing behaviour ■ Turns off TV for 30 seconds every time the sister is teased ■ Access to the TV is a positive reinforcer ■ Removing will cause the child to stop teasing behaviour ○ Time out procedure ■ A child is made to leave the play area and sit alone after performing undesirable behaviour ■ With the removal of positive reinforcers, the child will stop the unwanted response ○ Punishment and omission training both lead to the same decrease in responding ■ Very different in instrumental conditioning ● Escape training - removal of a negative reinforcer ○ Escaping a bad situation ○ Constant negative reinforcer being presented that learner is motivated to remove ○ When performing a specific response ■ A negative reinforcer can be removed ■ Increase in that response behaviour ○ E.g. the Landlord bangs on the ceiling which leads to music being turned off ■ The landlord has learned that he can avoid the music (negative reinforcer) by initiating the response of a banging on the ceiling ● With all types of instrumental conditioning ○ It proceeds best when the consequence immediately follows the response ○ E.g. Punishment training ■ To train a rat to stop using its left paw ■ Present a mild electric shock every time it is used ■ More difficult if there was a long period between using the left paw (response) and receiving the shock (consequence) ■ Learning the contingency is part of the problem Acquisition and shaping ● Contingencies ○ Classical conditioning ■ Organism learns contingency between stimulus and biologically event ○ Instrumental conditioning ■ The process of acquisition leads to learning the contingency between a response and its consequences ● Acquisition of instrumental conditioning is measuring the rate of responding to the new behaviour

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The response rate for a given behaviour will move up a notch leading to the acquisition When line comparing the cumulative number of responses (Y-axis) to the amount of time (x-axis) ○ The flat horizontal line indicates the subject is not responding ○ Slope upward indicates when a response has been made ○ The pattern depends on the subject, the complexity of the behaviour and the type of reinforcement used ● E.g. experiment ○ A pigeon placed in a special cage with a keyhole, when the keyhole is pecked, a grain of seed is released ○ Initially, the pigeon is unaware of the contingency ○ Over time, the pigeon will come across the keyhole ○ It then learns the contingency between the behaviour and the consequence ○ Behaviours such as pecking a keyhole can be learned without careful guidance ○ The response of pecking leads to reinforcement with a food reward ○ This special type of instrumental conditioning is called autoshaping ● Not all behaviours can be autoshaped ○ Some instrumental responses are too complex for the subject to discover by themselves ● Shaping by successive approximation ○ Complex behaviours organized into smaller steps ■ Build up to a full response ■ Each step can be reinforced through reward training ■ Successive approximation leads to the final complex behaviour ■ As the subject progress through these stages, the criteria for the reward became stricter Generalization and discrimination ● Discriminative stimulus - SD or S+ ○ Signals when contingency between the response and reinforcement is on ● S-delta - S○ Indicate when the contingent relationship is not valid ● E.g. Pigeon learns to peck a keyhole to receive food ○ When a green light is on, the contingent relationship is valid ■ Peaking leads to reward ○ When a clicking sound is on, the contingent relationship is not valid ■ Peaking does not lead to reward ○ The green light is the SD ○ The clicking sound is S-delta ● Generalization gradient also happens to the discriminative stimulus in instrumental conditioning ○ E.g. In the pigeon example ■ The bird learns to respond with peaking when the green light is on ● Also will respond with peaking behaviour to lights of a similar wavelength to the original SD

○ The range is captured on an SD generalization gradient SD and S-delta can be manipulated ○ Can train subjects to better discriminate between stimuli ● Association between the behaviour and an instrumentally conditioned outcome can be lost through extinction ○ The process of learning no longer predicts an outcome ○ E.g. the pigeon peaking at the keyhole ■ The presence of green light will lead to food ■ Then teach the pigeon that red light leads to the absence of food ● Greenlight is an SD ● Redlight is an S-delta ■ When shown a yellow light, in between green and red ● The similarity of the stimulus to the S-delta (yellow light to red light) would interfere with the typical response expected given how similar the stimulus is to the SD (green light to yellow light) ● Therefore, the yellow light will not be treated like a blue light (equally similar to green light as is the yellow light) ● It is instead treated like a weak cue that prompts minimal responding ○ Extinction can be generalized across stimuli ● The difference between SD and CS ○ CS is paired with a US, elicit response reflexively ■ The response is involuntary and automatic ○ SD is paired with response-reinforcer outcome ■ The SD itself does not reflexively elicit the response ■ The SD sets the occasion for a response by signalling when the response-reinforce outcome relationship is valid ■ Instrumental conditioning is voluntary Schedules of Reinforcement ● Continuous reinforcement ○ When a response leads to a reinforcer on every trial ○ Not common in the real world ● Partial reinforcement ○ Can have reinforcement delivery determined by total responses (ratio) or time (interval) ■ The ratio schedule is based on the number of responses made by a subject which, determines when reinforcement is given ● E.g. pigeon on the FR-1 schedule is rewarded with food for each pecking response ○ On FR-10 schedule is rewarded with food for every 10 peaking response ■ The interval schedule is based on the time since the last response that was reinforced ●

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E.g. pigeon on FI-1 minute schedule is rewarded with food for the first pecking response after 1 minute period ○ Can earn up to 60 pellets of food ● Pigeon on the FI-10 schedule is rewarded with food for the first pecking response after a 10 minute period ○ Can earn up to 6 food pellets Both ratio and interval schedules can be either fixed or variable ■ Examples given on top are fixed schedules ● For an FR-10 schedule, only after exactly 10 pecks is food given Variable schedule twist ■ Rewards on a variable ratio and interval scales are provided following a variable amount of work or length of time ● E.g. VR 10 schedule ○ Pigeon must peck an average of 10 to get a food reward, but the exact number of pecks that yields reward changes across trials (the first trial = 8, the second trial = 12) ● E.g. VI-10 schedule ○ The average of 10 minutes will be reinforced. The exact time changes between trials (the first trial = 7 minutes, the second trial = 13 minutes) Four basic types of schedules ■ Fixed ratio (FR) ● Limit to how stingy an FR schedule can be ○ Too stingy will lead to ratio strain ○ E.g. pigeon won’t respond if FR-500 ● Piece work pay scales ○ A set amount of shirts for a set amount of pay ● Display record called pause and run pattern ○ The subject will pause with inactivity before beginning to next run of responding ○ E.g. if the pigeon is not hungry after the FR-20 schedule, it will pause before starting the next round, lack of motivation ○ Step wise pattern ■ Variable ratio (VR) ● Reinforcement delivered after a random number of responses around a mean ● E.g. slot machine, after a random number of plays set around a pre-set mean, slot machine returns rewards ● A cumulative record of responses reinforced on a variable ratio schedule may look like a diagonal line with no pauses ○ The slope of the variable ratio schedule reflects the average number of responses required before reinforcement is delivered ○ VR-10 will have a steeper slope than the VR-40 schedule

○ Steeper slope reflects the increased incentive Fixed interval (FI) ● Reinforcement is delivered follwoing the first response after a set interval of time ● FI schedules produce a cumulative record with a scallop pattern ○ Following reinforcement, there is a lull period which responding drops ○ Then slowly starts to pick up again and peaking just before the next reinforcement is scheduled ○ The individual does not want to miss the reinforcement window ○ There is no direct reinforcement for responding beforehand ■ Variable interval (VI) ● Could receive reinforcement at any time, there is an idea of how often reinforcement is likely to come up ● VI schedule tends to respond at a steady rate ○ Ensure not to miss an opportunity of reinforcement ● Straight-line on the cumulative record ○ More frequent reinforcement will support higher response rates ○ VI-2 minute will have a steeper slope than VI-6 minute slope Instrumental condit...