Lead exposure in early childhood can lead to severe cognitive and behavioral impairments in children that last well into adolescence and adulthood. Although researchers have looked at effects of early life lead exposure on a small number of genes involved in learning, memory, and brain development, research was lacking as to the full extent of the toxicity. New research from Thomas Jefferson University shows that over 3,500 genes in the hippocampus, a part of the brain involved in learning and memory are affected by lead poisoning. The work also shows that providing animals with stimulating environments early in life can reverse the large majority of these genetic changes, reinforcing the potentially important role of early-childhood education in combating the effects of lead poisoning.