Fig. 1.

Example of a rat tested on the place and response discriminations. In the place version, this rat was started from the S and W arms and always had to enter the N arm to receive a cereal reinforcement. In the response version, this rat was started from the E and W arms and always had to turn right to receive a cereal reinforcement. The arrows in the maze represent the correct navigation patterns to receive a reinforcement. ●, Food well containing cereal reinforcement.