Chapter 5: Instrumental Conditioning: Foundations

Chapter 5: Instrumental Conditioning: Foundations  Classical conditioning reflects how organisms adjust to events in their environment that they cannot directly control Instrumental behavior: behavior that occurs because it was previously instrumental (aka- influential) in producing certain consequences Law of effect: If a response in the presence of a stimulus is followed by a satisfying event, the association between the stimulus (S) and the response (R) is strengthened  If the response is followed by an annoying event, the S-R association is weakened.  Thorndike’s proposal is the basis for the compulsive nature of drug abuse Discrete-trial procedure: a method of instrumental conditioning in which the participant can perform the instrumental response only during specified periods, usually determined by either placement of the participant in an experiment chamber, or by the presentation of a stimulus.  Often conducted in a type of maze Free-Operant Procedures: a method of instrumental conditioning that permits repeated performance of the instrumental response without intervention from the experimenter.  Invented by Skinner to study more behavior in a more continuous manner  Used a Skinner box – a box that contains a small lever that the rat can push down repeatedly  Operant response: the effect that it has on the environment (ex- the lever press) Magazine training:  Many steps to produce lever-press responding in rat  1st – rat has to learn when food is available  Classical conditioning – the sound of the food delivery device is repeatedly paired with the delivery of the food  Food-delivery service is called: the food magazine  After enough pairings of the sound of the food magazine with food delivery, the sound comes to elicit a response: the animal goes to the food and pick up the food pellets  This phase called: magazine training  Once rearing over the lever has been established- the food pellet will be given only if the rat actually presses the lever – called shaping Instrumental conditioning Procedures:  Appetitive stimulus: a pleasant outcome  Aversive stimulus: an unpleasant outcome  Positive reinforcement: response produces an appetitive stimulus; produces an increase in response rate. (ex- father gives daughter a cookie when she puts her toys away)  Punishment: the response produces a aversive stimulus; effect punishment procedures produce a decline in the instrumental response. (ex- your boss criticizes you for being late to a meeting)  Negative Reinforcement: the response turns off an aversive stimulus; increase the instrumental response (ex- opening an umbrella to stop the rain from getting you wet)  Omission Training (AKA- differential reinforcement of other behavior (DRO)): the response prevents the delivery of a pleasant/appetitive stimulus; preferred method for discouraging human behavior ( ex- suspending someone’s driver’s license for driving drunk – withdrawal of the pleasure & privilege of driving) Fundamental Elements of Instrumental Conditioning:  The response  The outcome of the response (the reinforce)  The relation/contingency between the response and the outcome The Response  The nature of the response influences the outcome of negative reinforcement & punishment procedures  Behavioral variability vs. stereotypy o Variability in responding can be increased by reinforcement o In the absence of explicit reinforcement of variability, responding becomes more stereotyped with continued instrumental conditioning.  Relevance or belongingness o Belongingness: the theoretical idea that an organism’s evolutionary history makes certain responses fit or belong with certain rein forcers; facilitates learning. o Instinctive drift: a gradual drift of instrumental behavior away from the response required for reinforcement to species – typical, Or instinctive, responses related to the reinforce and to other stimuli in the experimental situation The Reinforcer:  Quality and quantity: if a reinforcer is very small and of poor quality, it will not be effective in increasing instrumental responding

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The effectiveness of a reinforcer depends also on how that reinforcer compares with others the individuals has experienced in the past  Positive contrast: elevated responding for a favorable reward resulting from prior experience with a less attractive outcome  Negative contrast: depressed responding for a small reward because of prior experience with a better outcome The Response-Reinforcer Relation:  2 relationships between a response and a reinforcer: o Temporal relation: refers to the time between the response and the reinforcer  Temporal contiguity: refers to the delivery of the reinforcer immediately after the response o Response-reinforcer contingency: refers to the extent to which the instrumental response is necessary and sufficient for the occurrence of the reinforcer  Immediate reinforcement more effective  A delay in the response makes it difficult to figure out which response deserves the credit for the reinforcer that is delivered  Overcome the delay by: o Secondary/conditioned reinforcer: a conditioned stimulus that was previously associated with the reinforcer (ex: verbal coaching – “good” “keep going”) o Marking procedure: a procedure in which the instrumental response is immediately followed by a distinctive event that makes the response more memorable and helps overcome the deleterious effects of delayed reinforcement  Superstitious behavior: behavior that increases in frequency because of accidental pairings of delivery of a reinforcer with occurrences of the behavior Learned-helplessness effect: interference with the learning of new instrumental responses as a result of exposure to inescapable and unavoidable aversive stimulus. Learned-helplessness hypothesis: a theoretical idea that assumes that during exposure to inescapable and unavoidable aversive stimulation participants learn that their behavior does not control environmental events. This reduces motivation to respond and disrupts subsequent instrumental conditioning.