Pfingst Laboratory

The Pfingst Laboratories at the Kresge Hearing Research Institute, under the direction of Bryan E. Pfingst, Ph.D., aim to improve hearing with the use of the cochlear implant. 

Goals

  • Increase speech recognition and quality of life for patients with cochlear implants by identifying ways to improve auditory-prosthesis stimulation strategies and post-deafening treatments
  • Examine the mechanisms underlying electrically-based hearing
  • Help provide for future developments in auditory prostheses by providing research training to a diverse population of undergraduates, graduate students, residents and postdoctoral trainees

Current Projects

Effects of Neural Preservation and Regeneration on Auditory Prosthesis Function

Neurotrophin gene therapy procedures are used to enhance preservation and/or regeneration of auditory nerve in deafened guinea-pig ears that have cochlear implants. Additional procedures are used to control tissue growth in the implanted ear. The functional effects of these procedures are assessed using animal psychophysics and electrophysiology. These functional measures are then compared to post-mortem histological measures. The research is done in collaboration with the lab of Yehoash Raphael, Ph.D.

Effects of Hearing Preservation on Cochlear Implant Function

Surgical procedures and post-surgical treatments are used to preserve acoustic hearing in ears with cochlear implants. This typically results in good to excellent preservation of the auditory nerve so that cochlear implant function can be enhanced by supplemental acoustic hearing and by improved condition of the electrically stimulated auditory nerve. Functional effects of these procedures in guinea pigs are assessed using animal psychophysics and electrophysiology. These functional measures are then compared to post-mortem histological measures. The research is done in collaboration with the laboratories of Richard A. Altschuler, Ph.D., and Josef M. Miller, Ph.D.

Development of a Totally Implantable Artificial Organ of Corti (CIAO)

The acoustic to electrical transducer for the CIAO is a series of piezoelectric transducers implanted in the scala tympani to translate vibrations in the cochlear fluids to electrical signals for auditory nerve stimulation. Functional effects of these devices are assessed in deaf, implanted guinea pigs using animal psychophysics, electrophysiology and complex-impedance measures. The work is done in collaboration with the laboratory of Karl Grosh, Ph.D., in the U-M Department of Mechanical Engineering. Experiments to enhance neural health and control fibrous tissue are conducted in collaboration with the laboratory of Yehoash Raphael, Ph.D.

Functional Assessment of Stimulation Sites Along the Cochlear Implant Electrode Array to Guide Speech-Processor Fitting Strategies in Humans with Cochlear Implants

Psychophysical and electrophysiological procedures are used to assess the health of the sensory-neural structures near each individual stimulation site along the electrode array in human listeners who have multichannel cochlear implants. These data are then used to guide the fitting of the cochlear prosthesis speech processor to the individual subject. Effects of these procedures on speech recognition in quiet and noise are evaluated to determine what procedures result in the greatest improvement in hearing compared to standard fitting procedures. The research is done in collaboration with Kara Leyzac, Au.D., Ph.D., and Teresa A. Zwolan, Ph.D., director of the U-M Cochlear Implant Program.