title: Assessing stimulus and subject influences on auditory evoked potentials and their relation to peripheral physiology in green treefrogs (Hyla cinerea).
abstract: Anurans (frogs and toads) are important models for comparative studies of communication, auditory physiology, and neuroethology, but to date, most of our knowledge comes from in-depth studies of a relatively small number of model species. Using the well-studied green treefrog (Hyla cinerea), this study sought to develop and evaluate the use of auditory evoked potentials (AEPs) as a minimally invasive tool for investigating auditory sensitivity in a larger diversity of anuran species. The goals of the study were to assess the effects of frequency, signal level, sex, and body size on auditory brainstem response (ABR) amplitudes and latencies, characterize gross ABR morphology, and generate an audiogram that could be compared to several previously published audiograms for green treefrogs. Increasing signal level resulted in larger ABR amplitudes and shorter latencies, and these effects were frequency dependent. There was little evidence for an effect of sex or size on ABRs. Analyses consistently distinguished between responses to stimuli in the frequency ranges of the three previously-described populations of afferents that innervate the two auditory end organs in anurans. The overall shape of the audiogram shared prominent features with previously published audiograms. This study highlights the utility of AEPs as a valuable tool for the study of anuran auditory sensitivity.
authors.affiliation: College of Biological Sciences, University of Minnesota-Twin Cities, Saint Paul, MN 55108, USA.
authors.forename: Nathan P
authors.initials: NP
authors.lastname: Buerkle
authors.affiliation: Graduate Program in Neuroscience, University of Minnesota-Twin Cities, Minneapolis, MN 55455, USA. Electronic address: schro641@umn.edu.
authors.forename: Katrina M
authors.initials: KM
authors.lastname: Schrode
authors.affiliation: Department of Ecology, Evolution and Behavior, University of Minnesota-Twin Cities, Saint Paul, MN 55108, USA.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Bee
mesh_terms: D000818:Animals; D001001:Anura / Q000033:anatomy & histology / Q000254:growth & development / Q000502:physiology*; D001309:Auditory Threshold; D001933:Brain Stem / Q000033:anatomy & histology / Q000254:growth & development / Q000502:physiology; D016057:Evoked Potentials, Auditory, Brain Stem; D025461:Feedback, Physiological; D005260:Female; D007103:Immobilization; D008297:Male; D008954:Models, Biological; D003473:Neuromuscular Nondepolarizing Agents / Q000494:pharmacology; D009474:Neurons / Q000502:physiology; D015203:Reproducibility of Results; D012727:Sex Characteristics; D013045:Species Specificity; D013781:Texas; D014403:Tubocurarine / Q000494:pharmacology; D014828:Vocalization, Animal; D015430:Weight Gain
chemical_list: D003473:Neuromuscular Nondepolarizing Agents; D014403:Tubocurarine
keywords: Audiogram; Auditory brainstem response; Auditory evoked potentials; Communication; Green treefrog; Hearing