Who is calling the shots in hormone-behavior relationships? The answer is in your CORT.

Despite decades of experimental and descriptive studies in behavioral endocrinology, the vast majority of
organismal research has emphasized the role of changes in the concentration of circulating hormones,
with much less focus on the role of receptor expression in target tissues. Separately, while no one doubts
that changes in circulating steroid hormone concentrations can dramatically impact the expression of
behavior, there are few demonstrations of the reverse—that the expression of a behavior per se can drive
changes in endocrine activity. In this talk I will describe some recent projects in treefrogs aimed at testing
the idea that the neural expression of steroid receptors, along with experimentally elevated corticosterone
levels, explains variation in mate choosiness in females; and that clasping behavior in male frogs drives
rapid changes in secretory activity. The results provide hints that hormone-behavior relationships may be
more rapid, dynamic, and bidirectional than conventionally thought.