The term terminal nerve neuron (TNN) refers to one of two types of neuron found in the vomeronasal organ. The other is the accessory olfactory receptor neuron (OLRa). The TNN is a spontaneously firing neuron that releases gonadotropin releasing hormone (GnRH) into the olfactory epithelium (OLE). There it can potentiate or inhibit depolarization and hyperpolarization of OLRa's ( Wirsig-Wiechmann-2001 ). GnRH is the key regulator of the reproductive system. Assuming that TNN's function similarly to other sources of GnRH in the brain, it is first stimulated to function by the surge of estrogens and androgens at puberty ( Marquez-2022 ). In that case, by modulating the excitatory influence of sex-related pheromones on OLRa's, they enable the OLRa's to transmit information that the stimulus is a sexually active adult of the same species to the accessory olfactory bulb (OLBa). Behavioral significance of the TNN is supported by the observation that lesions of the terminal nerve (tn) produces s deficit in male mating behavior in the hamster ( Wirsig-Wiechmann-2001 ). Updated 31 Jul 2024.