Sound localization of world and head-centered space in ferrets

Abstract

The location of sounds can be described in multiple coordinate systems that are defined relative to ourselves, or the world around us. World-centered hearing is critical for stable understanding of sound scenes, yet it is unclear whether this ability is unique to human listeners or generalizes to other species. Here, we establish novel behavioral tests to determine the coordinate systems in which non-human listeners (ferrets) can localize sounds. We found that ferrets could learn to discriminate sounds using either world-centered or head-centered sound location, as evidenced by their ability to discriminate locations in one space across wide variations in sound location in the alternative coordinate system. Using infrequent probe sounds to assess broader generalization of spatial hearing, we demonstrated that in both head and world-centered localization, animals used continuous maps of auditory space to guide behavior. Single trial responses of individual animals were sufficiently informative that we could then model sound localization using speaker position in specific coordinate systems and accurately predict ferrets' actions in held-out data. Our results demonstrate that non-human listeners can thus localize sounds in multiple spaces, including those defined by the world that require abstraction across traditional, head-centered sound localization cues.