Toxicant effects on central connectivity have not been extensively characterized. Studies of developmental neurotoxicity have typically described malformations arising from damage to neuronal precursors. Toxicants may also affect later stages of neural development. In particular, they may disrupt the postnatal development of sensory systems. The purpose of the paper is to describe the effects of postnatal damage to peripheral sensory nerves on the trigeminal pathway of the rodent somatosensory system. These studies, which have demonstrated that neonatal peripheral nerve damage produces persistent alterations in central connections, have implications for the study of developmental neurotoxicology.