Figure 2 Latent learning results.
The obvious way of getting a rat to learn a maze is to provide it with a food incentive at the end. Rats always rewarded in this way show a gradual decrease in errors (turning the wrong way in a maze like that shown in figure 1). Rats who are never rewarded continue to make many errors. But animals run initially without any food incentive (in this case for the first ten days), who have apparently learned nothing, show an immediate improvement in performance after just one reward, proving that some learning had taken place on the non-rewarded trials, even though this was not obvious in the rats' behaviour until rewards were given. (After Tolman and Honzik, 1930)