Weanling rats were raised in an enriched or an impoverished environment. The enriched rats subsequently learned the Morris water maze faster than their impoverished counterparts. The enriched rats, both maze-trained and untrained, showed higher choline acetyltransferase (ChAT) activity in the caudate than did the impoverished, untrained rats. Maze training increased caudate ChAT in impoverished rats. Enriched but not impoverished rats showed increased hippocampal and anterior cortical ChAT activity after maze training. Thus, enrichment causes a long-lasting increase in caudate acetylcholine (Ach) synthesis and it also primes cortex and hippocampus to respond to a training experience with increased Ach synthesis.