Which psychologist used cats in puzzle boxes to study learning?

Which psychologist used cats in puzzle boxes to study learning? Edward Thorndike.

Edward Lee Thorndike used homemade puzzle boxes to investigate how cats learned to escape. A cat was placed inside a box containing a mechanism such as a lever, loop, or pedal. At first, the animal tried many ineffective movements; eventually, an accidental successful action opened the door and allowed it to reach a reward, usually food.

Thorndike repeated the trials and measured escape times. The cats generally escaped more quickly with practice, producing gradual learning curves rather than a sudden breakthrough. He interpreted this pattern as trial-and-error learning rather than human-like insight.

From these experiments, Thorndike formulated the law of effect: behaviors followed by satisfying consequences become more likely to recur in similar situations. His work helped establish the study of animal learning and influenced later behaviorists, including B. F. Skinner.

A common mix-up is confusing Thorndike’s puzzle box with Skinner’s operant-conditioning chamber. Thorndike’s apparatus was designed around escape and trial-and-error behavior; Skinner’s later chamber allowed researchers to control reinforcement contingencies more systematically.