Skinner’s Experiments Skinner’s experiments extend Thorndike’s thinking, especially his law of effect. This lawstates that rewarded behavior is likely to occur again. Yale University Library
Operant Chamber Using Thorndikes law of effect as a starting point, Skinner developed the Operantchamber, or the Skinner box, to study operant conditioning. Edition by Michael P. Domjan, 2005. Used with permission From The Essentials of Conditioning and Learning, 3rd by Thomson Learning, Wadsworth Division Walter Dawn/ Photo Researchers, Inc.
Operant Chamber The operant chamber, or Skinnerbox, comes with a bar or key that an animalmanipulates to obtain areinforcer like food orwater. The bar or key is connected to devices that record the animal’s response.
Shaping Shaping is the operant conditioning procedurein which reinforcers guide behavior towards the desired target behavior through successive approximations.
Types of ReinforcersReinforcement: Any event that strengthens the behavior it follows. A heat lamp positively reinforces a meerkat’s behavior in the cold. Reuters/ Corbis
Primary & Secondary Reinforcers1. Primary Reinforcer: An innately reinforcing stimulus like food or drink.2. Conditioned Reinforcer: A learned reinforcer that gets its reinforcing power through association with the primary reinforcer.
Immediate & Delayed Reinforcers1. Immediate Reinforcer: A reinforcer that occurs instantly after a behavior. A rat gets a food pellet for a bar press.2. Delayed Reinforcer: A reinforcer that is delayed in time for a certain behavior. A paycheck that comes at the end of a week. We may be inclined to engage in small immediate reinforcers (watching TV) rather than large delayed reinforcers (getting an A in a course) which require consistent study.
Reinforcement Schedules1. Continuous Reinforcement: Reinforces the desired response each time it occurs.2. Partial Reinforcement: Reinforces a response only part of the time. Though this results in slower acquisition in the beginning, it shows greater resistance to extinction later on.
Ratio Schedules1. Fixed-ratio schedule: Reinforces a response only after a specified number of responses. e.g., piecework pay.2. Variable-ratio schedule: Reinforces a response after an unpredictable number of responses. This is hard to extinguish because of the unpredictability. (e.g., behaviors like gambling, fishing.)
Interval Schedules1. Fixed-interval schedule: Reinforces a response only after a specified time has elapsed. (e.g., preparing for an exam only when the exam draws close.)2. Variable-interval schedule: Reinforces a response at unpredictable time intervals, which produces slow, steady responses. (e.g., pop quiz.)
PunishmentAn aversive event that decreases the behavior it follows.
Punishment Although there may be some justification for occasional punishment (Larzelaere &Baumrind, 2002), it usually leads to negative effects.1. Results in unwanted fears.2. Conveys no information to the organism.3. Justifies pain to others.4. Causes unwanted behaviors to reappear in its absence.5. Causes aggression towards the agent.6. Causes one unwanted behavior to appear in place of another.
Positive Reinforcement• Behavior or response increases when followed by the addition of a reinforcing stimulus – Examples: • Dog treats • Teacher’s praise • Good grades = money
Negative Reinforcement• Behavior or response increases when followed by the removal, avoidance or escape of an unpleasant stimulus – Examples: • Taking an aspirin • Crying = toy • Alarm clock
More examples – Negative Reinforcement1. Taking aspirin to relieve a headache.2. Hurrying home in the winter to get out of the cold.3. Giving in to an argument or to a dog’s begging.4. Fanning oneself to escape the heat.5. Leaving a movie theater if the movie is bad.6. Smoking in order to relieve anxiety.7. Following prison rules in order to be released fromconfinement.8. Feigning a stomachache in order to avoid school.9. Putting on a car safety belt to stop an irritatingbuzz.10. Turning down the volume of a very loud radio.11. Putting up an umbrella to escape the rain.12. Saying “uncle” to stop being beaten.
Positive Punishment• Behavior or response decreases when followed by the addition or application of an aversive stimulus – Examples: • Spanking • Bad behavior = more chores • Yelling at spouse
Negative Punishment• Behavior or response decreases when followed by the removal of a reinforcing stimulus – Examples: • Dude I’m grounded • Time-out • Driving drunk = loss of license
Identify the Type of Conditioning Tim is learning to play the trombone. His teacher notices that Tim likes baseball so she begins to give him a baseball card every time he successfully learns to play a new piece of music. How is Tim being conditioned?
Identify the Type of Conditioning Anna ate something that upset her stomach. Anika suggested that she take a special mixture of peppermint tea and saltine crackers. Anna took the cure and felt much better. The next time Anna felt sick to her stomach, she fixed herself peppermint tea and crackers. How has Anna been conditioned?
Identify the Type of Conditioning Jen was in a hurry to meet her friends for dinner. Jen is going 85 in a 65 and gets pulled over by a police officer. The officer gives her a ticket. How is Jen being conditioned?
Intrinsic MotivationIntrinsic Motivation:The desire to perform abehavior for its ownsake.Extrinsic Motivation:The desire to perform abehavior due topromised rewards orthreats of punishments.
Skinner’s Legacy Skinner argued that behaviors were shaped byexternal influences instead of inner thoughts and feelings. Critics argued that Skinnerdehumanized people by neglecting their free will. .Falk/ Photo Researchers, Inc
Applications of Operant Conditioning Skinner introduced the concept of teachingmachines that shape learning in small steps and provide reinforcements for correct rewards. In School LWA-JDL/ Corbis
Applications of Operant ConditioningReinforcers affect productivity. Many companies now allow employees to share profits and participate in company ownership. At work
Applications of Operant Conditioning At HomeIn children, reinforcing good behavior increases the occurrence of these behaviors. Ignoring unwanted behavior decreases their occurrence.