Meeting Abstract
Many behavior patterns that are strongly modulated by hormones, such as mate choice are mediated by visual processing. Yet, little is known about the effect of reproductive hormones on the retina, in particular, which is critical to understanding how visual signals are processed during these behaviors. This project focuses on the retina itself by examining the effects of sex steroids on spectral sensitivity, or the ability to detect differences in color signals. Our hypothesis is that hormones modulate stimulus sensitivity in the retina during reproductively receptive phases and influence mate choice behavior through modulation of color vision. We tested the effect hormones on color vision using the green treefrog (Hyla cinerea), which detect and respond to wavelengths spanning (and beyond) the human visible light spectrum. Experiments used electroretinograms (ERGs) to compare stimulus threshold and response amplitude in the retina of reproductive and non-reproductive female frogs. Additionally, we compared retinal activation before and after injections of human chorionic gonadotropin (hCG), which causes secretion of estrogen and progesterone in females and testosterone in males. Our findings indicate that reproductive state and hormone injections cause an increase in sensitivity to particular wavelengths of light in female frogs. Future experiments will determine the functional consequences of this endocrine modulation of vision using behavioral assays under different wavelengths of light.
