Widespread acceptance for gonadal steroid control of brain and behavior involved decades of research on diverse animal species held in captivity or observed in nature. We hope this work will join with that of other species to embolden acceptance of neurosteroidal signaling as a core property of vertebrate neurobiology. Combined with evidence for rapid steroidal control of behavior, these studies firmly establish a neuromodulatory role for avian neurosteroids.

Our work in a songbird points to synaptic synthesis of neuroactive steroids and fast, peri-synaptic membrane actions. These studies show that steroidogenic transporters and enzymes are present in the songbird brain and their expression and/or activities are subject to developmental, seasonal or short-term regulation. Here we review work out of our lab and others highlighting advances to our understanding of brain steroid synthesis and action using songbirds as animal models. No doubt, studies across diverse phyla will continue to be crucial for revealing the true significance of neurosteroidogenesis to proper function of the vertebrate brain. Comparative studies have been vital for establishing the key actions of gonadal and adrenal hormones on brain and behavior. The long-held dogma that the brain is a target of steroids produced by peripheral organs has delayed widespread acceptance of the functional importance of neurosteroidogenesis.

Wehrenberg arnold