title: Little effect of natural noise on high-frequency hearing in frogs, Odorrana tormota.
abstract: Ambient noise influences acoustic communication in animals. The concave-eared frogs (Odorrana tormota) produce high-frequency sound signals to avoid potential masking from noise. However, whether environmental noise has effect on the high-frequency hearing of frogs is largely unclear. By measuring the auditory evoked near-field potentials (AENFPs) from the torus semicircularis of the midbrain at frequencies 1-23 kHz in the presence of three noise levels, we found no significant difference in the peak-to-peak amplitude, threshold and latency of AENFP between low-level (35 dB SPL) background noise and mid-level (65 dB SPL) broadcast natural noise. For a natural noise level of 85 dB SPL, AENFP amplitude decreased and threshold and latency increased at frequencies 3-13 kHz. Spike counts evoked by stimuli at the best excitatory frequency under 85 dB SPL natural noise exposure were lower in 7-kHz CF neurons than in exposures to 35 and 65 dB SPL noise. However spike counts were similar for 14- and 20-kHz CF neurons at the three exposure levels. These findings indicate that environmental noise does not mask the responses of high-frequency tuned auditory neurons, and suggest that the acoustic communication system of O. tormota is efficiently adapted to noisy habitats.
authors.affiliation: Department of Basic Medical Sciences, Medical College of Xiamen University, Xiamen, 361102, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Basic Medical Sciences, Medical College of Xiamen University, Xiamen, 361102, China.
authors.forename: Han
authors.initials: H
authors.lastname: Yang
authors.affiliation: Department of Basic Medical Sciences, Medical College of Xiamen University, Xiamen, 361102, China.
authors.forename: Guang-Lei
authors.initials: GL
authors.lastname: Hu
authors.affiliation: Department of Basic Medical Sciences, Medical College of Xiamen University, Xiamen, 361102, China.
authors.forename: Shan
authors.initials: S
authors.lastname: Li
authors.affiliation: State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.
authors.forename: Zhi-Min
authors.initials: ZM
authors.lastname: Xu
authors.affiliation: Department of Basic Medical Sciences, Medical College of Xiamen University, Xiamen, 361102, China. qizhi@xmu.edu.cn.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Qi
authors.affiliation: State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China. shenjx@ibp.ac.cn.
authors.forename: Jun-Xian
authors.initials: JX
authors.lastname: Shen
mesh_terms: D000161:Acoustic Stimulation; D000162:Acoustics; D000704:Analysis of Variance; D000818:Animals; D001001:Anura / Q000502:physiology*; D001309:Auditory Threshold; D004777:Environment; D005072:Evoked Potentials, Auditory / Q000502:physiology; D006309:Hearing / Q000502:physiology*; D009622:Noise
keywords: Auditory evoked near-field potential; Concave-eared frog; Noise; Odorrana tormota; Single TS unit