HORMONALLY-INDUCED ALTERATIONS IN SYNAPTIC ORGANIZATION IN THE ADULT NERVOUS-SYSTEM

In recent years, there is growing evidence that vertebrate neural circuits involved in reproduction retain a considerable amount of plasticity in adulthood. Gonadal steroid hormones cause dramatic changes in the synaptic organization of these circuits to regulate the expression of reproductive behavior. Two model systems are described to illustrate such changes: the neural system controlling song in passerine birds, and the spinal nucleus of the bulbocavernosus system in the rat spinal cord.