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 hu-man 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 vo-calizations 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 underly-ing song development and maintenance. Here, I present an overview of recent work on the function of the AFP includ-ing 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-corti-cal 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 chal-lenges of songbird research in understanding basal ganglia function.