5.02 Classical and Operant Conditioning Psychiatry review for the USMLE Step 1 Exam Classical Conditioning: Pavlovian conditioning discovered by Ivan Pavlov, a Russian physiologist known for his experiments with dogs. Learning through association. Example: Conditioning dogs to respond to a noise the way they would respond to meat. Involves associating an unconditioned stimulus with a new conditioned stimulus to elicit the same response. Process of Classical Conditioning: Start with a stimulus that produces a response (e.g., smelling pizza makes you hungry). Pair the stimulus and response with an unconditioned stimulus (e.g., receiving a text indicating pizza delivery). Eventually, the conditioned stimulus (the text notification) alone elicits the conditioned response (mouth watering). Extinction and Spontaneous Recovery in Classical Conditioning: If the conditioned stimulus (text notification) is presented without the unconditioned stimulus (pizza), the conditioned response (mouth watering) will weaken and eventually extinguish. Spontaneous recovery may occur, where the conditioned behavior briefly reappears after a period of extinction. Terms in Classical Conditioning: Unconditioned stimulus (US): Triggers a response unconditionally. Unconditioned response (UR): The response elicited by the unconditioned stimulus. Conditioned stimulus (CS): Initially neutral stimulus that becomes associated with the unconditioned stimulus. Conditioned response (CR): The response elicited by the conditioned stimulus. Operant Conditioning: Developed by B.F. Skinner. Learning occurs through rewards and punishments for behavior. Three types of responses: neutral operants, reinforcers, and punishers. Examples of Operant Conditioning: Positive reinforcement: Giving a child candy for good behavior. Negative reinforcement: Taking away a child's phone until homework is done to increase desired behavior. Positive punishment: Using physical force as punishment (not recommended). Negative punishment: Taking away a child's phone to decrease unwanted behavior. Different Schedules of Reinforcement: Continuous Reinforcement: Positive reinforcement every time a specific behavior occurs. Fixed Ratio Reinforcement: Reinforcement after a specified number of correct responses. Fixed Interval Reinforcement: Reinforcement after a fixed time interval with at least one correct response. Variable Ratio Reinforcement: Reinforcement after an unpredictable number of responses. Variable Interval Reinforcement: Reinforcement after an unpredictable amount of time. Summary: Classical conditioning involves learning through association of stimuli. Operant conditioning involves learning through rewards and punishments for behavior.