VA Ann Arbor Healthcare System Research Services
Auditory and Vestibular Systems Research Core
Auditory and Vestibular Systems Research Core
The Auditory and Vestibular Systems Research Core at the VA Ann Arbor Healthcare System has standard research capabilities for noise exposure, behavioral and physiological assessment of vesitbular and auditory function; tissue collection, dissection, and molecular biology. Our group examines hearing and balance disorders and how noise, blast, aging and other factors affecting the Veteran population can contribute to these disorders. Studies of the auditory system examine deafness, noise- and age-related hearing loss, as well as tinnitus. Studies of the vestibular system examine the role of noise exposure and aging in reduced balance and increased fall risk. Both auditory and vestibular studies focus on identification of underlying physiological and cellular mechanisms and development of mechanisms-based therapeutics for prevention, reversal, and treatment.
Affiliated Investigators
Richard Altschuler, PhD, Professor, Otolaryngology-Head and Neck Surgery, University of Michigan
Keith Duncan, PhD, Associate Professor, Otolaryngology-Head and Neck Surgery, University of Michigan
Michael King, PhD, Professor, Otolaryngology-Head and Neck Surgery, University of Michigan
Courtney Stewart, PhD, Research Biologist, VA Ann Arbor Healthcare System
Equipment and Resources
Noise Exposure
Free-Field Noise Exposure System: A custom noise exposure booth (ETS Lindgren RE-141) modified for increased noise reduction and internal reflection, ensuring consistent noise exposures and a safe workspace during intense (120 dB SPL) free-field noise exposure. A window and internal LED light allow for frequent monitoring of rats during free-field noise exposures at safe sound levels. The noise exposure booth is equipped with a Crown Audio DSI2000 2-Channel Power Amplifier, two 12” Eminence Kappalite 3012HO Speakers, and a dedicated computer workstation.
Insert Earphone Noise Exposure System: A Tucker Davis Technologies (TDT) ABR/DPOAE workstation is used to deliver impulse noise that mimics military-relevant small-arms fire-like noise through a JBL Commercial Series Amplifier 180Z connected to a closed-field magnetic speaker (TDT MF1).
Electrophysiology
ABR/DPOAE System: Auditory brainstem responses (ABRs) and vestibular short-latency evoked potentials (VsEPs) are measured with a Tucker Davis Technologies (TDT) ABR/DPOAE workstation (TDT, Alachua, FL USA). An additional power amplifier (Parasound Zamp v.3) is used to drive a head shaker (Labworks ET-132-203) to produce vestibular stimuli. Closed field electromagnetic speakers (TDT MF1) are used to deliver auditory stimuli. Measurements are collected in a radio frequency shielded booth. An additional speaker, amplifier, and signal mixer are available for auditory masking during physiological measurements.
Behavior
Balance Beam: A 1-meter balance beam with infrared sensors is used for objective measurement of crossing time. Infrared sensor breaks are detected as voltage changes and are recorded on a dedicated computer workstation through a DATAQ DI-2108 data acquisition unit.
Head Sensors: Custom-built wireless head sensors are used to record head motion during active motor tasks. Each sensor is equipped with a 9 degree-of-freedom inertial measurement unit and sends real-time, earth-referenced head acceleration and velocity data to a dedicated computer workstation.
