Neural mechanisms of birdsong learning: basal ganglia circuits and reinforcement learning model

Abstract

Oscine songbirds learn to produce complex vocalizations, song, by imitating their tutor’s song in early life, just as human infants learn to produce speech sounds from adults. Birds develop their song in a highly complex sensorimotor learning process, in which they try to match their own vocalizations to the memorized information of tutor song. The anterior forebrain pathway (AFP) plays a major role in this sensorimotor learning process, and recent studies regarding this pathway have revealed important mechanisms underlying song development and maintenance. Here, I present an overview of recent work on the function of the AFP including my work, and review influential models that explain how birds develop and maintain their song using the AFP. The AFP has also recently attracted great interest as a tractable model system for studying the function of basal ganglia-cortical loop circuits, because the AFP is highly homologous to mammalian basal ganglia circuits but specialized for a single task, song learning. I review recent work of the AFP on this topic, and discuss possible contributions and future challenges of songbird research in understanding basal ganglia function.