Performance of Malnourished Rats on the Hebb-Williams Closed-Field Maze Learning Task

Abstract

3 groups of rats were subjected to protein restrictions during development, while two control groups received normal diets throughout the experiment. The protein restricted groups were raised on dams that were maintained on 12% protein diets and were weaned at 21 days of age to a diet containing 3% protein. One group was maintained on the diet for 7 wk. and then rehabilitated on a 21% protein diet while a second group was maintained on the 3% protein diet for 27 wk. and then rehabilitated for 7 wk. At this time these two groups and a control group maintained on a normal dam prior to weaning and maintained on 21% protein throughout the experiment were tested on a Hebb-Williams maze for liquid reinforcement. The third diet-restricted group was maintained on the 3% protein diet throughout the experiment and was tested in the Hebb-Williams maze along with a control group raised on 21% diet when they were 6 mo. of age. The nonrehabilitated group made the most errors and differed significantly from both the control groups and the rehabilitated groups. The rehabilitated groups did not differ significantly from one another, but they made significantly more errors than the nonrehabilitated groups. The effects of early diet restriction were compared with the effects of early environmental restrictions in their effects on problem-solving behavior.