Relation between the severity of early malnutrition and the effects of later frontal cortical lesions in rats

Abstract

Rats with an early history of severe malnutrition received frontal cortical (FC) lesions or control operations at 90 days of age. These severely malnourished groups were compared with each other and with moderately malnourished and well-fed groups (FC and control) for acquisition and three reversals of a tactile discrimination (rough-smooth). Main effects of lesion and nutrition were found for acquisition and reversals. The groups with malnutrition plus frontal lesions displayed the poorest performance. Although the severely and moderately malnourished groups did not differ in acquisition of the discrimination, the severely malnourished group made more reversal errors. The severely malnourished rats also showed greater brain growth retardation (size and weight) than the moderately malnourished rats. These results indicate that the effects of early dietary history and the reaction to a later, acute brain injury may be additive under certain circumstances.