Effects of environmental enrichment on gene expression in the brain

An enriched environment is known to promote structural changes in the brain and to enhance learning and memory performance in rodents [Hebb, D. O. (19 47) Am. Psychol. 2, 306-307]. To better understand the molecular mechanisms underlying these experience-dependent cognitive changes, we have used high -density oligonucleotide microarrays to analyze gene expression in the brai n. Expression of a large number of genes changes in response to enrichment training, many of which can be linked to neuronal structure, synaptic plast icity, and transmission. A number of these genes may play important roles i n modulating learning and memory capacity.