The study of song is particularly useful for understanding mechanisms driving the learning and production of vocalizations in addition to mechanisms driving plasticity of the cellular composition in the underlying neural circuits. In the songbird, Gambel’s white-crowned sparrow (Zonotrichia leucophrys gambelii), the production of song and the underlying neural circuit that controls this song changes dramatically between breeding and nonbreeding seasons. We can exploit the tight relationship between the breeding state of song and the song circuit to ask questions like, "does adult neurogenesis impact song quality?", among others.
We routinely record and quantify song production rate and quality as a proxy for putative* cellular changes occurring in HVC with any experimental manipulation.
*We also routinely examine the cellular content of HVC directly.