Adult birdsong is actively maintained by error correction

Abstract

Humans learn to speak by a process of vocal imitation that requires the availability of auditory feedback. Similarly, young birds rely on auditory feedback when learning to imitate the songs of adult birds, providing one of the few examples of nonhuman vocal learning. However, whereas humans continue to use auditory feedback to correct vocal errors in adulthood, the mechanisms underlying the stability of adult birdsong are unknown. Here we show that like human speech, adult birdsong is maintained by error correction. We perturbed the pitch (fundamental frequency) of auditory feedback in adult Bengalese finches using custom-designed headphones. Birds compensated for the imposed auditory error by adjusting the pitch of song. When the perturbation was removed, pitch returned to baseline. These results show that adult birds correct vocal errors by comparing auditory feedback to a sensory target and suggest that lifelong error correction is a general principle of learned vocal behavior.