Distribution of 3H-uridine-5 in rat brain areas after exposure to various training tasks - an autoradiographic analysis.

Operant schedules were used to isolate components of a training task and the distribution of radioactivity into various brain areas was studied using high resolution autoradiography. Rats exposed to a visual stimulus change showed more labelling in hippocampal area CA1 than littermates exposed to no stimulus change. Rats exposed to a non-cued contingency change showed higher labelling in hippocampal areas CA2 and CA4 than littermates exposed to a cued contingency change. The results suggest that hippocampal changes in RNA synthesis may be related more to the aversive conditions of the training task than to specific learning changes.