Behavioral measures of signal recognition thresholds in frogs in the presence and absence of chorus-shaped noise

• Published in: The Journal of the Acoustical Society of America Vol. 126; no. 5; pp. 2788 - 2801
• Main Authors: Bee, Mark A., Schwartz, Joshua J.
• Format: Journal Article
• Language: English
• Published: Melville, NY Acoustical Society of America 01.11.2009; American Institute of Physics
• Subjects: Acoustics; Animals; Anura; Anura - physiology; Auditory Threshold - physiology; Behavior, Animal - physiology; Bioacoustics; Exact sciences and technology; Female; Fundamental areas of phenomenology (including applications); Male; Models, Biological; Noise; Physics; Psychoacoustics; Sound Localization - physiology; Vocalization, Animal - physiology; Bioacoustics; Behavioral analysis; Threshold
• ISSN: 0001-4966; 1520-8524; 1520-9024; 1520-8524
• DOI: 10.1121/1.3224707

Anuran amphibians are superb animal models for investigating the mechanisms underlying acoustic signal perception amid high levels of background noise generated by large social aggregations of vocalizing individuals. Yet there are not well-established methods for quantifying a number of key measures of auditory perception in frogs, in part, because frogs are notoriously difficult subjects for traditional psychoacoustic experiments based on classical or operant conditioning. A common experimental approach for studying frog hearing and acoustic communication involves behavioral phonotaxis experiments, in which patterns of movement directed toward sound sources indicate the subjects' perceptual experiences. In this study, three different phonotaxis experiments were conducted using the same target signals and noise maskers to compare different experimental methods and analytical tools for deriving estimates of signal recognition thresholds in the presence or absence of "chorus-shaped noise" (i.e., artificial noise with a spectrum similar to that of real breeding choruses). Estimates of recognition thresholds based on measures of angular orientation, response probabilities, and response latencies were quite similar in both two-choice and no-choice phonotaxis tests. These results establish important baselines for comparing different methods of estimating signal recognition thresholds in frogs tested in various masking noise conditions.