The perceptual analysis of acoustic scenes involves binding together sounds from the same source and separating them from other sounds in the environment. In large social groups, listeners experience increased difficulty performing these tasks due to high noise levels and interference from the concurrent signals of multiple individuals. While a substantial body of literature on these issues pertains to human hearing and speech communication, few studies have investigated how nonhuman animals may be evolutionarily adapted to solve biologically analogous communication problems. Here, I review recent and ongoing work aimed at testing hypotheses about perceptual mechanisms that enable treefrogs in the genus Hyla to communicate vocally in noisy, multi-source social environments. After briefly introducing the genus and the methods used to study hearing in frogs, I outline several functional constraints on communication posed by the acoustic environment of breeding "choruses". Then, I review studies of sound source perception aimed at uncovering how treefrog listeners may be adapted to cope with these constraints. Specifically, this review covers research on the acoustic cues used in sequential and simultaneous auditory grouping, spatial release from masking, and dip listening. Throughout the paper, I attempt to illustrate how broad-scale, comparative studies of carefully considered animal models may ultimately reveal an evolutionary diversity of underlying mechanisms for solving cocktail-party-like problems in communication.
Bibliographical noteFunding Information:
I thank Elyse Sussman and Mitchell Steinschneider for the invitation to contribute to this special issue; Michael Caldwell, Norman Lee, Katrina Schrode, Jessie Tanner, Jessica Ward, and two anonymous reviewers for helpful feedback on previous versions of this manuscript; Michael Caldwell, Norman Lee, Vivek Nityananda, Katrina Schrode, Sandra Tekmen, Alejandro Vélez, and Jessica Ward for their hard work and dedication to much of the research described here; and the National Institute on Deafness and Other Communication Disorders ( R03DC008396 and R01DC009582 ) and the National Science Foundation ( IOS 0842759 ) for funding my research. All original research reported herein followed the “Principles of laboratory animal care” (NIH publication No.86-23, revised 1985) and laws of the U.S.A., and was approved by the University of Minnesota's Institutional Animal Care and Use Committee (#1202A10178).
- Auditory grouping
- Auditory stream segregation
- Comodulation masking release
- Dip listening
- Perceptual restoration
- Spatial release from masking