Effect of response effort on the reward value of distinctively flavored food pellets

This study was designed to test whether distinctively flavored food pellets, used as rewards for lever-pressing by rats, would acquire different reward values as a function of the differential effort involved in making the lever pressing response which would be predictable from the concept of cognitive dissonance. Subjects were seven Long-Evans strain hooded rats, 301-308 days old at the start of the study and had had their body weights reduced to 80%, of their free-feeding weights. Testing was done in a Y-maze, with food pellets associated with the difficult lever-press response serving as the reward for one choice and pellets associated with the easy lever-press response for the other. Analysis showed there was no preference in the choice of either the "easy" or the "difficult" pellets, the choice not being significantly different from chance. This indicated that the effort involved in making a response did not affect the reward strength of food pellets when used to reward a response with a different topography.