Research

Research in my lab focuses on the general question of how experience acts on the nervous system to shape behavior.  Our goal is to account for learning by understanding the sensory stimuli that drive change, how and where those stimuli are represented in patterns of neural activity, and how those patterns act to modify behavior.  We hope both to reveal general learning mechanisms, and to understand how variations in those mechanisms give rise to individual differences in behavior.  Hence, we are interested in how the nervous system changes over the course of development to give rise to 'critical periods' for learning and how innate variations between individuals interact with experience to give rise to differences in learned behaviors.  Towards this end, we employ a variety of behavioral, neurophysiological and genetic approaches to investigate vocal learning in songbirds.

We study vocal learning in songbirds because it is a quantifiable natural behavior that exhibits a variety of general features of vertebrate learning, and it is subserved by a well-elucidated and accessible set of brain regions.  Song learning includes a perceptual learning component during which young birds listen to and memorize the song of an adult 'tutor' as well as a sensorimotor learning component, during which they use auditory feedback to gradually refine their initially 'babbling' vocalizations so that they progressively resemble the previously memorized tutor song.  In many species, this learning is limited to an early 'critical period', and is also strongly influenced by social interactions.  These features make song learning a rich model for studying the mechanisms that contribute to sensory and sensorimotor learning in general, and to certain components of human language learning in particular; speech acquisition exhibits strikingly similar requirements for memorization and vocal practice during early development and for maintained auditory feedback throughout life.