Mouse Auditory Testing Core Facility

National Institute On Deafness And Other Communication Disorders

Investigators

Linked publications, trials & patents

Abstract

The Mouse Auditory Testing (MAT) Core assists investigators at the National Institute on Deafness and Other Communication Disorders (NIDCD) and their collaborators with tests of auditory and vestibular function in mice. Two physiological measures of auditory function are employed in the MAT Core: the auditory brainstem response (ABR) and distortion-product otoacoustic emissions (DPOAEs). The ABR is an evoked potential that can be used to estimate hearing thresholds. DPOAEs are soft sounds that are recorded in the ear canal using a small microphone. DPOAEs can be used to screen for hearing loss and to evaluate inner ear function; specifically, the presence of DPOAEs indicates normal function of outer hair cells in the inner ear. Vestibular sensory evoked potentials (VsEPs) are measured to assess vestibular function. VsEPs are generated by the vestibular nervous system in response to linear movements of the head and provide information about function of the otolith organs (utricle and saccule). The Core assists with noise exposure protocols as needed. Dr. Fitzgerald conducted training in auditory function testing with three NIDCD investigators. Ten NIDCD investigators conducted auditory function testing independently with support from the MAT Core. Dr. Fitzgerald trained two investigators from the Section on DNA Repair at the National Institute on Aging (NIA), Dr. Jae-Hyeon Park (Contract Scientist) and Dr. Burcin Duan Sahbaz (Post-Doctoral Visiting Fellow), in ABR waveform interpretation. Dr. Fitzgerald consulted on ABR and DPOAE testing and data analyses with members of Dr. Meghan Drummond's lab at Regeneron. Dr. Fitzgerald consulted on ABR test protocols and equipment with Dr. Donna Perry, Dr. Lucy Cong, Dr. Ian Crozier and colleagues at the National Institute of Allergy and Infectious Diseases (NIAID) Integrated Research Facility in conjunction with Drs. Carmen Brewer and Kelly King from the Audiology Unit at the NIDCD. Dr. Fitzgerald continued a collaboration with John Kakareka (Electronics Engineer, Instrumentation Development and Engineering Application Solutions (IDEAS), National Institute of Biomedical Imaging and BioEngineering (NIBIB)) to develop a custom probe for DPOAE measurements. Drs. Fitzgerald and Wafa collaborated with Vivek Kamath and Taek Oh from the Information Systems Management Branch, Data Management Section (NIDCD), on creation of a Filemaker Pro database that will be used to record auditory and vestibular test data collected in the Core. Core staff began the pilot phase to test the new database in early September 2022. Dr. Fitzgerald, Dr. Wafa, and Ms. Krasnopolsky collaborated on and/or supported projects conducted in eight NIDCD labs. Information on collaborations with specific laboratories is listed below. Inner Ear Gene Therapy Program (PI: Wade Chien, M.D.) Dr. Fitzgerald trained Samantha Lau (Pre-Doctoral IRTA Fellow) in auditory test procedures. Dr. Fitzgerald provided support to Ms. Lau, Kevin Isgrig (Biologist), Yasuko Ishibashi (Post-Doctoral Fellow), and Jianliang Zhu (Biologist) for multiple projects investigating the use of gene therapy to remediate hearing loss or vestibular dysfunction. Drs. Fitzgerald and Wafa collaborated with Kevin Isgrig, Mhamed Grati (Staff Scientist), and Dr. Chien on a project investigating the use of gene therapy to remediate vestibular dysfunction in mutant mice. Section on Sensory Cell Biology (PI: Lisa Cunningham, Ph.D.) Dr. Fitzgerald oriented Drs. Cathy Sung and John Lee (Post-Doctoral Fellows) to the Core's auditory test procedures. Dr. Fitzgerald provided support to Dr. Sung, Dr. Lee, and Dr. Katharine Fernandez (Staff Scientist) for projects investigating the mechanisms behind and prevention of hearing loss caused by ototoxic medications. Laboratory of Molecular Genetics (PI: Thomas Friedman, Ph.D.) Dr. Fitzgerald collaborated on multiple projects examining auditory function in various mutant mouse strains, including projects with Dr. Inna Belyantseva (Staff Scientist), Rabia Faridi (Post-Doctoral Visiting Fellow), and Elizabeth Wilson Bernhard (Biologist), and on a collaboration between the Chien lab and Dr. Belyantseva. Section on Molecular Biology and Genetics (PI: Isabelle Roux, Ph.D.) Dr. Fitzgerald completed training in auditory testing with Kerstin Valente (Biologist) and supported independent auditory testing by Kelly Hedger (Biologist). Drs. Fitzgerald and Wafa collaborated with Ms. Valente, Ms. Hedger, and Dr. Roux on projects that included auditory and vestibular function testing in several mouse lines segregating alleles of Slc26a4 with missense mutations identified in patients with hearing loss and enlarged vestibular aqueduct. Auditory Development and Restoration Program (PI: Michael Hoa, M.D.) Dr. Fitzgerald supported auditory testing by Rafal Olszewski (Biologist) on a mouse model of fluctuating hearing loss. Section on Structural Cell Biology (PI: Bechara Kachar, M.D.) Dr. Fitzgerald collaborated with Dr. Kachar to characterize auditory function in a recently developed mutant mouse. Laboratory of Cochlear Development (PI: Matthew Kelley, Ph.D.) Dr. Fitzgerald supported auditory function testing of mutant mice by Dr. Braulio Peguero (Post-Doctoral Fellow). Drs. Fitzgerald and Wafa began a collaboration with Dr. Beatrice Mao (Post-Doctoral Fellow) on a project to characterize auditory function in mutant mice. Section on Sensory Cell Regeneration and Development (PI: Doris Wu, Ph.D.) Drs. Wafa and Fitzgerald collaborated with Dr. Youngrae Ji (Post-Doctoral Visiting Fellow) and Dr. Wu on a project examining vestibular function in conditional knockout mice.