EFFECTS OF INFANTILE UNDERNUTRITION ON ADULT LEARNING IN RATS - METHODOLOGICAL AND DESIGN PROBLEMS

Research bearing upon possible confounding variables involved in the study of the effects of early undernutrition upon later learning in rats was examined. The procedures currently used to produce undernutrition also produce changes in the infant rats'' social and environmental conditions. Evidence from other sources indicate that these types of changes may play an important role in the determination of later behavior. Attribution of the causes of later effects of undernutrition must be reinterpreted in light of this evidence. Early undernutrition and the variables confounded with it produce effects on later size, motor ability, behavior toward food, ability to absorb and use food and to adjust to food deprivation, and responsivity to aversive and environmental stimuli. Thus, the effects of undernutrition upon later learning may be due to the effects upon these other variables which can affect learning performance rather than upon learning capacity. Strategies for dealing with these problems depend upon the goals of the researcher.