Skinner designed a soundproof apparatus, often equipped with a lever or bar, with which he conducted his experiments in operant conditioning. this has been called a:
I believe the answer is: Skinner box. Skinner box is a box design that often used by researchers to study animal behavior. Skinner box consist of two important features: - Food dispensers where researchers could give rewards for the subjects - Electrical grid that could be used to impose punishment to the subject.