ABSTRACT
The experimental study of learning has been a major contributor to the ability of scientists and practitioners to produce, analyze, and control learned behavior in humans and nonhumans, in both the laboratory and in everyday life. During the first half of the 20th century, laboratory research systematically advanced the study of learning beyond descriptive and anthropomorphic accounts by introducing two powerful reinforcement procedures that reliably produced and controlled learned behavior. One of these procedures is Pavlovian conditioning—the presentation of reward contingent on a predictive cue (as in signaling proximate food to your dog by opening the cupboard where food is stored). The other is operant conditioning—the presentation of reward contingent on the performance of a specific behavior (as in presenting a treat to your dog only when it holds up a paw, or giving a weekly allowance to a child only after she does her chores). Elements of Pavlovian and operant procedures often intertwine, as in your signaling a car trip to the dog by picking up your keys (based on Pavlovian pairings of key sounds and trips in the car), followed by requiring the dog to sit before you open the car door (based on an operant contingency in which access to the car follows the required response of sitting).
