psych chapter 7 learning

learning

process by which experiences produce a relatively enduring change in an organism’s behaviour or capabilities, measured by changes in performance

habituation

decrease in the strength of response to a repeated stimulus

• different from sensory adaptation

• adaptive, conserves energy

sensitization

an increase in the strength of response to a repeated stimulus

• can also be adaptive, increased response to danger

• increases sensitivity to sounds after a loud, startling noise

• some mental health conditions (anxiety, PTSD)

classical conditioning

organism learns to associate 2 stimuli such that one stimulus comes to produce a response that originally was produced only by the other stimulus

• ex: Pavlov’s dogs - dogs learned to salivate at the found of a bell because it was repeatedly paired with food

  • before conditioning: neutral stimulus (bell) → nothing, UCS (food) → UCR (salivating)

  • during conditioning: CS (bell) + UCS (food) → UCR (salivating)

  • after conditioning: CS (bell) → CR (salivating)

• acquisition: refers to period during which response is being learned

extinction

if CS is presented repeatedly in absense of UCS, CR weakens and eventually disappears

spontaneous recovery

reappearance of a previously extinguished CR after rest period without new learning trials

stimulus generalization

when CR is acquired, organism responds not only to original CS but also to stimuli similar to it

• ex: Little Albert experiment

higher order conditioning

neutral stimulus becomes a CS after being paired with an already established CS

exposure therapy

basic goal is to expose phobic patient to feared stimulus (CS) without any UCS, allowing extinction to occur

aversion therapy

attempts to condition an aversion (a replusion) to a stimulus that triggers unwanted behaviour by pairing it with a noxious UCS

• short term results that fade over time

operant conditioning

• are not elicited responses trigger by a stimulus, are emitted (voluntary responses)

• instrumental learning: organism’s behaviour is instrumental in bringing about certain outcomes

Thorndike’s law of effect

in a given situation, response followed by satisfying consequence will become more likely to occur and response followed by unsatisfying consequence outcome less likely to occur

Skinner’s analysis of operant conditioning

• operant behaviour: organism operates on its environment in some way

  • emits responses that produce certain consequences

• operant conditioning: type of learning in which behaviour is influenced by its consequences

reinforcement

a response is strengthened (increase in frequency of response) by an outcome that follows it

• positive reinforcement: something pleasurable is presented, ex: receive praise for a job well done → response strengthened by subsequent presentation of a stimulus

• negative reinforcement: something aversive is removed, ex: when throat is sore, take a lozenge → sore throat gone → response strengthened by subsequent removal of avoidance of a stimulus

punishment

response is weakened by outcome that follows it

• positive punishment: something unpleasant is presented, ex: touch hot stove → burn finger, produce rapid results

• negative punishment: something pleasurable is removed, ex: late for curfew → car keys taken

analysis of operant behaviour involves:

• antecedents (A) → stimuli that are present before the behaviour occurs

• behaviours (B) → that organism emits

• consequences (C) → follows behaviour

• relations between A, B, and C are called contingencies

operant extinction

weakening and eventual disappearance of a response because it is no longer reinforced

• resistance to extinction: degree to which non-reinforced responses persist

discriminative stimulus

a signal that a particular response will now produce certain consequences

• ex: a green light signalling it’s okay to cross the street (behaviour: crossing, reinforcement: safety)

primary reinforcers

stimuli that an organism naturally finds reinforcing because they satisfy biological needs

secondary/conditioned reinforcers

stimuli that have no inherent value but become motivating through association with primary reinforcers

• ex: money, praise, grades

shaping

reinforcing successive approximations toward a final response

• ex: teaching a child to brush their teeth by praising small improvements until they master the full routine

chaining

used to develop a sequence of responses by reinforcing each response with the opportunity to perform the next response

• ex: making tea, break into manageable steps (get kettle, fill with water, boil, add tea bag, pour water, add milk/sugar)

  • link and reinforce: teach each step individually, then link them, reinforcing the completion of the entire sequence

operant generalization

an operant response occurs to a new antecedent stimulus or situation that is similar to the original one

operant discrimination

an operant response will occur to one antecedent stimulus but not to another

continuous reinforcement schedule

every response of a particular type is reinforced

partial reinforcement schedule

every response of a particular type are reinforced

partial reinforcement (intermittent reinforcement): only some responses are reinforced

• ratio schedules: certain percentage of responses are reinforced

• interval schedules: certain amount of time must elapse between reinforcements, regardless of how many correct responses might occur during that interval

• fixed schedule: reinforcement always occurs after fixed number of responses or after fixed interval of time

• variable schedule: required number of responses or time interval varies at random around an average

fixed ratio schedule

reinforcement is given after a fixed number of responses

• ex: FR-3 means reinforcement occurs after fixed number of responses

variable ratio schedule

reinforcement is given after a variable number of correct responses, based on average

• ex: VR-3 schedule means that, on average, 3 responses are required for reinforcement

fixed interval schedule

the first correct response that occurs after a fixed interval is reinforced

variable interval schedule

reinforcement given for first response that occurs after a variable time interval

escape conditioning

organisms learn a response to terminate an aversive stimulus

• escape behaviours acquired and maintained through negative reinforcement

• ex: if a loud alarm goes off (aversive), you press the snooze button (behaviour) to stop the noise (reinforcement)

avoidance conditioning

organism learns a response to avoid an aversive stimulus completely

• learn to respond before aversive stimulus even begins

• ex: a person with a history of migraines takes preventative medication to avoid the onset of a migraine

two-factor theory of avoidance learning

avoidance learning first involves the classical conditioning of fear, followed by learning operant responses that avoid an anticipated aversive stimulus and thus are reinforced by anxiety reduction

• ex: a dog learning to jump a barrier after hearing a buzzer to avoid a shock

  • the buzzer (CS) becomes scary (classical conditioning), and jumping (response) stops the buzzer and prevents the shock (negative reinforcement), reducing fear and strengthening the jump

token economics

desirable behaviours quickly reinforced with tokens

• ex: teacher gives students stickers for completing their homework or participating in class

applied behaviour analysis (behaviour modification)

combines a behavioural approach with scientific method to solve individual and societal problems

• usually based on positive reinforcement

preparedness

through evolution, animals are biologically “prewired” to easily learn behaviours related to their survival as a species

conditioned taste aversion

pairing smell and taste of food (CS) with toxin or illness-producing agent (UCS) produces CR

instinctive drift

a conditioned response drifts back towards instinctive behaviour

cognitive model of learning (S-O-R)

in between stimulus (S) and response (R), there is an organism’s mental representation of world (O)

Edward Tolman

learning provides knowledge, and based on knowledge, organisms develop expectancy

• ex: a rat learning in a lab maze doesn’t just form a habit; it develops an expectation that turning left at a specific junction will lead to a food reward

latent learning

learning that occurs but is not demonstrated until there is incentive to perform

• ex: a student who learns the route to school by riding in the car for months, but doesn’t actually drive until the parent is unable to drive them; they can then navigate to school because they had previously absorbed the route knowledge

observational learning

learning that occurs by observing behaviour of a model

• 4 steps: attention, retention, reproduction, motivation

• ex: Bobo doll experiment - showed children learn aggressive behaviours through observational learning (modeling) by imitating adults, even repeating aggressive words and actions they saw towards an inflatable doll