Impaired selective attention in methylazoxymethanol-induced microencephalic rats

Abstract

Prenatal treatment of rats on gestation day 15 with methylazoxymethanol (MAM) caused forebrain microencephaly. Several behavioral tests were performed when the rats had reached an adult age. MAM treated rats were hyperactive, and were severely impaired in the acquisition of successive position reversal in a T-maze. The microencephalic rats failed also to demonstrate contextual control of latent inhibition (the stimulus preexposure effect) in taste-aversion conditioning. These results indicate that MAM treatment disrupts attentional processes and that this may account for the learning impairment.