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Combining Classical and Operant Conditioning Avoidance Conditioning Classical and operant conditioning often take place in the same situation. We saw this in Rescorla’s fear conditioning experiment: Presenting a CS while dogs jumped back and forth to avoid shock increased or decreased the rate of jumping. In Rescorla’s experiment, the avoidance procedure (operant conditioning) had no warning signal for the shocks; they came at certain times. In another type of avoidance procedure, signalled avoidance, there is a warning signal before the shock. Combining Classical and Operant Conditioning Avoidance Conditioning Signalled Avoidance Warning signal (tone) Avoidance response Aversive stimulus (shock) If there is no avoidance response, the warning signal ends with shock. Combining Classical and Operant Conditioning Avoidance Conditioning Signalled Avoidance Warning signal (tone) Aversive stimulus (shock) Note that the warning signal is paired with shock. This is classical conditioning. The tone will become a CS and produce a CR of fear. Combining Classical and Operant Conditioning Avoidance Conditioning Signalled Avoidance Warning signal (tone) Aversive stimulus (shock) Key Point: The warning signal will become an aversive stimulus because it produces a fear CR. Aversive stimuli are negative reinforcers. They reinforce responses that remove them. Combining Classical and Operant Conditioning Avoidance Conditioning Signalled Avoidance Warning signal (tone) Avoidance response Aversive stimulus (shock) If the avoidance response occurs before the shock, the tone goes off immediately and no shock is given on that trial. Combining Classical and Operant Conditioning Avoidance Conditioning Signalled Avoidance Warning signal (tone) Avoidance response Removal of the aversive warning signal negatively reinforces the avoidance response. The avoidance response occurs faster and faster on later trials because it receives negative reinforcement. This is operant conditioning. Combining Classical and Operant Conditioning Avoidance Conditioning The 2-Process Theory of Avoidance Learning Avoidance behavior is not reinforced by avoidance of the aversive stimulus! It is reinforced by termination of the warning signal. Process 1: Classical Conditioning: The warning signal becomes aversive through pairings with the aversive stimulus (fear conditioning). Process 2: Operant Conditioning: Avoidance responses are negatively reinforced by termination of the warning signal. Combining Classical and Operant Conditioning Avoidance Conditioning The 2-Process Theory of Avoidance Learning Pros Key prediction: Delay of reinforcement weakens behavior. When an avoidance response occurs, if the warning signal goes off after a delay, the avoidance response should occur less often. Warning signal (tone) Avoidance response Delay of reinforcement This prediction was supported (Kamin, 1956). Combining Classical and Operant Conditioning Avoidance Conditioning The 2-Process Theory of Avoidance Learning Cons 1. Unsignalled avoidance: Avoidance learning can take place without a warning signal (e.g., Rescorla’s experiment). 2. No extinction of avoidance response: Avoidance responding should stop because the warning signal is not paired with shock on these trials, but the avoidance response keeps going. Why? Combining Classical and Operant Conditioning Avoidance Conditioning Cognitive Theory of Avoidance Learning The subject forms two kinds of “expectancies”: 1. Stimulus-Outcome: Warning signal leads to shock if there is no response. 2. Response-Outcome: Avoidance response leads to safety (no shock). To weaken avoidance response, these expectancies must be weakened through disconfirmation. Avoidance response keeps going because Expectancy #1 not tested and Expectancy #2 is repeatedly confirmed. Combining Classical and Operant Conditioning Avoidance Conditioning Cognitive Theory of Avoidance Learning Supporting evidence: Response Prevention ( “Flooding”) procedure. It’s used to eliminate an avoidance response when there is no longer a threat of being shocked. Physically prevent the subject from making the avoidance response while the warning signal is on. New expectancies are formed: 1. Stimulus-Outcome: Warning signal leads to NO shock if there is no response. 2. Response-Outcome: NOT responding leads to safety.