BRAIN RNA METABOLISM IN RAT DURING LEARNING

32 male Holtzman rats were pretrained to asymptote on a Y maze spatial discrimination for water reinforcement. Tritiated cytidine was then injected intravenously as an RNA precursor. Experimental Ss were immediately subjected to an average of 5.6 successive spatial reversals to criterion, whereas the controls were continued on the original discrimination, both for 60 min., before decapitation. RNA synthesis proved to be 25% higher in the experimental hippocampus, and pools of tritiated cytidine or its metabolites were 15 and 17% higher in the experimental hippocampus and pyriform cortex. Since sensory and motor factors were equated between groups, these chemo-EEG effects were probably related either to frustration of nonreward or, considering the hippocampal literature, perhaps more likely to learning or memory processes. (32 ref.) (PsycINFO Database Record (c) 2006 APA, all rights reserved). © 1969 American Psychological Association.