1Listen to the audio lecture while viewing these slidesPsychology 100Introduction to Psychology1Chapter 7: Learning & ConditioningModule 7.3: Operant/Instrumental Conditioning2Psyc 100 Psyc 100 –– Introduction to PsychologyIntroduction to PsychologyLearning and Consequences: Operant/Instrumental Conditioning• Procedure for studying how organisms learn about the consequences of their own voluntary actions• Also called instrumental conditioning• Example: Learning that studying leads to a good exam grade• Important early idea in study of learning: Law of effect (Thorndike) • If a response in a particular situation is followed by a satisfying consequence, it will be strengthened; if followed by an unsatisfying consequence, it will be weakenedFig. 7.103Psyc 100 Psyc 100 –– Introduction to PsychologyIntroduction to PsychologyFig. 7.114Psyc 100 Psyc 100 –– Introduction to PsychologyIntroduction to PsychologyFig. 7.125Psyc 100 Psyc 100 –– Introduction to PsychologyIntroduction to PsychologyHow Do You Know When to Respond?• Discriminative stimulus: Stimulus situation that sets the occasion for a response to be followed by reward or punishment• Can be a particular situation or thing in the environment• Response happens in the presence of that situation/thing• May produce the behavior in response to a similar stimulus (stimulus generalization), unless it doesn’t produce same reward (stimulus discrimination)6Psyc 100 Psyc 100 –– Introduction to PsychologyIntroduction to PsychologyFig. 7.1327Psyc 100 Psyc 100 –– Introduction to PsychologyIntroduction to PsychologyReinforcement• Response consequences that increase likelihood of responding in a similar way again•Two kinds:• Positive reinforcement: Event that, when presented after a response, increases likelihood of that response occurring again• Negative reinforcement: Event that, when removed after a response, increases likelihood of that response occurring again8Psyc 100 Psyc 100 –– Introduction to PsychologyIntroduction to PsychologyHow Positive Reinforcement Works• Usually involves an appetitive stimulus -something the organism needs, likes, wants• Example: Food, water, reinforcing activities• But: Can be learned (conditioned reinforcers)• Example: Money• Bliss point: Baseline level of satisfaction with an event/stimulus; varies by person• Response deprivation theory: Events are reinforcing as long as they move you toward your bliss point• Example: Eating is reinforcing when you are very hungry9Psyc 100 Psyc 100 –– Introduction to PsychologyIntroduction to PsychologyHow Negative Reinforcement Works• Response leads to removal of some stimulus• Example: Shutting off a loud alarm clock•Two kinds:• Escape conditioning• Example: Animal learns to escape an ongoing shock• Avoidance conditioning• Example: Animal learns to escape first to avoid shock10Psyc 100 Psyc 100 –– Introduction to PsychologyIntroduction to PsychologyPunishment• Consequences that decrease the likelihood of responding in a similar way again• Two kinds; they lower likelihood of response happening again when they:• Are presented after response (positive punishment)• Example: Sentencing someone to jail• Are removed after response (negative punishment) • Example: Charging a fine (that is, removing money)11Psyc 100 Psyc 100 –– Introduction to PsychologyIntroduction to PsychologySchedules of Reinforcement• Rule that an experimenter uses to determine when particular responses will be reinforced• Strongly affects speed and strength of learning• Continuous: Every response followed rapidly by reinforcement• Example: Salesperson paid for each sale• Partial: Reinforcement delivered only some of the time•Ratio•Interval12Psyc 100 Psyc 100 –– Introduction to PsychologyIntroduction to PsychologyPunishment: Practical Considerations• Does effectively suppress behavior• Example: A child fighting with a sibling• Limitation: Does not promote better, alternative behavior• Example: Does not teach a child to cooperate with sibling• Better: Reinforce an alternative response• Other possible negative side effects:• Can be too strong or forceful, creating physical/emotional trauma• Can produce anger, resentment, aggression313Psyc 100 Psyc 100 –– Introduction to PsychologyIntroduction to PsychologyRatio Schedules• Fixed-ratio: Number of responses required for reinforcement stays the same• Example: Salesperson paid for every 10 sales• Tend to produce steady, consistent rates of responding, but might stop for a period after reinforcement• Extinction when reinforcement no longer given• Variable-ratio: A certain number of responses required for reinforcement, but this number changes• Example: Salesperson paid after some number of sales, but doesn’t know how many• Extinction takes much longer14Psyc 100 Psyc 100 –– Introduction to PsychologyIntroduction to PsychologyInterval Schedules• Fixed-interval: Reinforcement delivered for first response after a fixed interval of time• Example: Salesperson paid for first sale in each week, but no others until next week begins• Tend to produce low rates of responding• “Scalloping” pattern• Variable-interval: Allotted time before a response will yield reinforcement changes• Example: Salesperson paid for first sale on a randomly chosen day15Psyc 100 Psyc 100 –– Introduction to PsychologyIntroduction to PsychologyFig.