Building a bird brain: sculpting neural circuits for a learned behavior

Development in animals is frequently characterized by periods of heightened capacity for both neural and behavioral change. So-called sensitive periods of development are windows of opportunity in which brain and behavior are most susceptible to modification. Understanding what factors regulate sensitive periods constitutes one of the main goals of developmental neuroscience. Why is the ability to learn complex behavioral patterns often restricted to sensitive periods of development? Songbirds provide a model system for unraveling the mysteries of neural mechanisms of learning during development. Like many songbirds, zebra finches (Taeniopygia guttata) learn a specific vocal pattern during a restricted period early in life. Young birds must hear songs produced by members of their species; this auditory experience is thought to engender specific changes in the brain to guide the process of vocal learning. Many studies of the songbird system have focused on examining relationships between brain development and learning. One goal of this work is to elucidate mechanisms that regulate basic processes of neural development, and in so doing to shed light on factors governing the emergence of a complex learned behavior.