Jill B. Firszt, PhD

Otolaryngology—Head and Neck Surgery
Director, Cochlear Implant Program

Dr. Firszt’s clinical and research interests include bilateral and unilateral cochlear implants in adults and children, asymmetric hearing and unilateral haring loss, speech recognition, behavioral and electrophysiologic measures with electrical stimulation and optimization of speech processor mapping.


The Firszt Lab is under the direction of Dr. Jill Firszt, Professor in the Department of Otolaryngology and Director of the Cochlear Implant Program at Washington University School of Medicine. The lab is engaged in ongoing research with adults and children who have hearing loss in one or both ears and may use a cochlear implant or hearing aid. As treatment options continue to evolve it is critical that best patient care is founded in scientific research. Current research objectives include investigating physiological changes that arise from hearing loss and exploring how those changes, along with other factors, interact and effect behavioral or functional outcomes with various interventions, e.g. bilateral cochlear implantation or bimodal device use.

Current Areas of Research in Adults and Children

  • Bilateral Cochlear Implantation
  • Asymmetric Hearing Loss
  • Unilateral Hearing Loss
  • Single Sided Deafness and Cochlear Implantation
  • Revised Indications for Cochlear Implantation
  • Behavioral and Electrophysiologic Measures with Electrical Stimulation
  • Optimization of Speech Processor Programming/Mapping
  • Team

Current projects

The Firszt Lab is engaged in ongoing research with adults and children who have hearing loss in one ear or both and may use a cochlear implant or a hearing aid. In addition, many of our studies include control groups of volunteer participants who have normal hearing.

Bilateral Cochlear Implantation

Several longitudinal studies are underway that include adult and pediatric bilateral cochlear implant recipients. For adults and children who receive implants sequentially (first one ear and then the other with varying amounts of time between the surgeries), we are studying the impact that the first cochlear implant has on both benefit and the rate of benefit obtained from the second cochlear implant. In a study of young children, some of whom receive simultaneous cochlear implants and others who receive one cochlear implant and continue to use a hearing aid on the other ear, we are studying the longitudinal outcomes resulting from two implants or an implant and a hearing aid at a young age.

Asymmetric Hearing Loss

Current studies with both adults and children examine the amount of benefit hearing-impaired individuals with significant asymmetrical sensorineural hearing loss obtain from bimodal hearing, that is acoustic input through a hearing aid in one ear and electric input through a cochlear implant in the opposite ear. Study results will assist in identifying factors that influence outcomes for these individuals.

Unilateral Hearing Loss

Individuals with unilateral hearing loss have normal hearing in one ear and significant hearing loss in the other ear. We are investigating effects of this asymmetry in hearing using both new behavioral techniques and physiologic imaging tools. Additionally, studies may point to variables that influence outcomes in adults and children with unilateral hearing loss.

Single Sided Deafness and Cochlear Implantation

Initial studies are underway to investigate the efficacy of cochlear implantation of the deaf ear in individuals who have single sided deafness, i.e. individuals who are deaf in one ear have normal or near-normal hearing in the other ear. Our studies will help determine whether participants are able to use the acoustic signal from the normal (or near normal) hearing ear and the electric signal from cochlear implantation of the deaf ear effectively.

Behavioral and Electrophysiologic Measures with Electrical Stimulation

Performance with cochlear implants varies considerably from one individual to another. Research studies are underway to assess the relation between behavioral outcomes with cochlear implants and neurophysiologic processes that may underlie speech processing and recognition. This line of research combines listening tasks with neurophysiologic responses from the same individuals.

Optimization of Speech Processor Programming/Mapping

As cochlear implant technology advances, studies are needed to investigate optimization of speech processor parameters to allow for maximum speech recognition in quiet and noise for cochlear implant recipients, both adults and children. During these studies, the task of evaluating input and output speech processing parameters is undertaken for individuals who receive unilateral and bilateral cochlear implants.

Interested in Participating?

We are currently enrolling study participants who meet the following criteria:

  • Adults who are deaf in one ear and hear normally in the other ear
  • Children (school age) who are deaf in one ear and hear normally in the other ear
  • Individuals who use one or two cochlear implants (adults and children)

If you are interested in learning more about our studies, please send your name, age, phone number, and e-mail address to: firsztlab@ent.wustl.edu or call the lab at 314-747-0882.


R01 DC009010 (Jill Firszt, PI)


Effects of Asymmetric Hearing in Acoustic Listeners and Cochlear Implant Users

The major goal of this project is to study the effects of asymmetric hearing in three patient groups, all are deaf in one ear but differ in their better hearing ear which has either normal hearing, moderate hearing loss or hears with a cochlear implant. This study will provide the basis for expanding criteria for implantation in one ear and establishing new criteria for implantation in both ears for children and adults. This study will also advance our understanding of plasticity and dominance of the neural pathways in deafness and guide intervention for patients with asymmetrical hearing loss.

P30 DC004665 (Richard A. Chole, PI)


Research Core Center for Auditory and Vestibular Studies

The Research Center provides centralized resources and facilities within the Department of Otolaryngology and supports NIDCD-funded research as well as the development of research projects that coincide with mission areas of the NIDCD. Currently, the Research Center comprises four research cores: Histology, Microscopy and Digital Imaging, Sensory Functional Testing and Clinical and Translational Research.


Firszt JB, Reeder RM, Dwyer NY, Burton H, Holden LK. Localization training results in individuals with unilateral severe to profound hearing loss. Hear Res, 2015, 48-55. Abstract

Davidson L, Firszt JB, Brenner C, Cadieux JH. Evaluation of hearing aid frequency response fittings in pediatric and young adult bimodal recipients. J Am Acad Audiol, 2015, 393-407. Abstract

Reeder RM, Cadieux JH, Firszt JB. Quantification of speech-in-noise and sound localisation abilities in children with unilateral hearing loss and comparison to normal hearing peers. Audiol Neurotol, 2015, 31-37. Abstract

Vincent C, Arndt S, Firszt JB, Fraysse B, Kitterick P, Papsin B, Snik A, Van de Heyning P, Deguine O, Marx M. Identification and evaluation of cochlear implant candidates with asymmetrical hearing loss. Audiol Neurotol, 2015, 87-89. Abstract

Reeder RM, Firszt JB, Holden LK, Strube M. A longitudinal study in adults with sequential bilateral cochlear implants: Time course for individual ear and bilateral performance. Jour Speech, Lang, Hear Res, 2014, 1108-1126. Abstract

Long CJ, Holden TA, McClelland GH, Parkinson WS, Shelton S, Kelsall DC, Smith ZM. Examining the Electro-Neural Interface of Cochlear Implant Users Using Pyschophysics, CT Scans, and Speech Understanding. J Assoc Res Otolaryngol, 2014, 1-12. Abstract

Dwyer NY, Firszt JB, Reeder RM. Effects of unilateral input and mode of hearing in the better ear: self-reported performance using the Speech,Spatial and Qualities of Hearing Scale. Ear Hear, 2014, 35(1): 126-136. Abstract

Firszt JB, Reeder RM, Holden TA, Burton, H, Chole RA. Changes in auditory perception and cortex resulting from hearing recovery after extended congenital unilateral hearing loss. Frontiers in Systems Neuroscience, 2013, 7(108): 1-11. Abstract

Holden, LK, Brenner, C, Reeder, RM, Firszt, JB. Postlingual adult performance in noise with HiRes 120 and Clear Voice Low, Medium and High. Coch Implant Int. 2013, 14(5): 276-286. Abstract

Burton H, Firszt JB, Holden TA, Agato A. Hearing thresholds and fmri of auditory cortex following eighth nerve surgery. Otolaryngol Head Neck Surg., 2013, 149: 492-499. Abstract

Cadieux J, Firszt JB, Reeder RM. Cochlear implantation in non-traditional candidates: Preliminary results in adolescents with asymmetric hearing loss. Otol Neurotol, 2013,34(3): 408-415. Abstract

Holden LK, Finley CC, Firszt JB, Holden TA, Brenner C, Potts LG, Gotter BD, Vanderhoof SS, Mispagel M, Heydebrand G. Factors affecting open-set word recognition in adults with cochlear implants. Ear Hear, 2013, 34(3): 342-360. Abstract

Firszt JB, Holden LK, Reeder RM, Waltzman SB, Arndt S. Auditory abilities after cochlear implantation in adults with unilateral deafness. Otol Neurotol, 2012, 33(8):1339-46. Abstract

Burton H, Firszt JB, Holden T, Agato A, Uchanski RM. Activation lateralization in human core, belt and parabelt auditory fields with unilateral deafness compared to normal hearing. Brain Res, 2012, 1454:33-47. Abstract

King SE, Firszt JB, Reeder RM, Holden LK, Strube M. Evaluation of TIMIT sentence list equivalency with adult cochlear implant recipients. J Am Acad Audiol, 2012, 23(5):313-331.Abstract

Firszt JB, Holden LK, Reeder RM, Cowdrey L, King S. Cochlear implantation in adults with asymmetric hearing loss. Ear Hear, 2012, 33(4):521-533.Abstract

Baudhuin J, Cadieux J, Firszt JB, Reeder RM, Maxson JL. Optimization of programming parameters in children with the advanced Bionics cochlear implant. J Am Acad Audiol, 2012, 23(5), 302-12.Abstract

Holden LK, Neely JG, Gotter BD, Mispagel KM, Firszt JB. Sequential bilateral cochlear implantation in a patient with bilateral Meniere’s disease. J Am Acad Audiol, 2012, 23(4), 256-68. Abstract

Tibbetts K, Ead B, Umansky A, Coalson R, Schlagger BL, Firszt JB, Lieu JE. Interregional brain interactions in children with unilateral hearing loss. Otolaryngol Head Neck Surg, 2011, 144(4), 602-611. Abstract

Firszt JB, Holden LK, Reeder RM, Cowdrey L Effects of asymmetric hearing loss in cochlear implant recipients. Audiol Neurotol, 2011, 16(S1), 15-17.Abstract

Holden LK, Reeder RM, Firszt JB, Finley CC. Optimizing the perception of soft speech and speech in noise with the Advanced Bionics cochlear implant system. Int J Audiol, 2011, 50(4), 255-269. Abstract

Firszt JB, Holden LK, Reeder RM, Skinner MW. Speech recognition in cochlear implant recipients: Comparison of standard HiRes and HiRes 120 sound processing. Otol Neurotol, 2009, 30(2), 146-52.Abstract

Uchanski RM, Davidson LS, Quadrizius S, Reeder R, Cadieux J, Kettel J, et al.Two ears and two (or more?) devices: A pediatric case study of bilateral profound hearing loss. Trends Amplif, 2009, 13(2), 107-23.Abstract

Firszt JB, Reeder RM, Skinner MW. Restoring hearing symmetry with two cochlear implants or one cochlear implant and a contralateral hearing aid. J Rehabil Res Dev, 2008, 45(5), 749-68.Abstract

Alkaf FM, Firszt JB. Speech recognition in quiet and noise in borderline cochlear implant candidates. J Am Acad Audiol, 2008,18(10), 872-82.Abstract

Buss E, Pillsbury HC, Buchman CA, Pillsbury CH, Clark MS, Haynes DS, et al. Multi-center U.S. Bilateral MED-EL cochlear implantation study: Speech perception over the first year of use. Ear Hear, 2008, 29(1), 20-32.Abstract

Firszt JB, Koch DB, Downing M, Litvak L. Current steering creates additional pitch percepts in adult cochlear implant recipients. Otol Neurotol, 2007, 28(5), 629-36.Abstract

Holden LK, Skinner MW, Fourakis MS, Holden TA. Effect of increased IIDR in the Nucleus Freedom cochlear implant system. J Am Acad Audiol, 2007, 18, 777-793.Abstract

Firszt JB, Ulmer JL, Gaggl W. Differential representation of speech sounds in the human cerebral hemispheres. The Anatomical Record Part A: Discoveries in Molecular, Cellular, and Evolutionary Biology, 2006, 288A(4), 345-57.Abstract

Firszt JB, Runge-Samuelson CL, Wackym PA. Intraoperative assessment of cochlear implant and auditory brainstem implant device function.Operative Techniques in Otolaryngology-Head and Neck Surgery, 2005,16(2), 131-9.

Holden LK, Vandali AE, Skinner MW, Fourakis MS, Holden TA. Speech recognition with the advanced combination encoder and transient emphasis spectral maxima strategies in nucleus 24 recipients. J Speech Lang Hear Res, 2005, 48(3), 681-701.Abstract

Firszt JB, Reeder RM. How we do it: tuning up a young child. Cochlear Implants Int, 2005, 6(4), 178-82.Abstract

Zwolan TA, Kileny PR, Smith S, Waltzman S, Chute P, Domico E, et al. Comparison of continuous interleaved sampling and simultaneous analog stimulation speech processing strategies in newly implanted adults with a Clarion 1.2 cochlear implant. Otol Neurotol, 2005, 26(3), 455-65.Abstract

Firszt JB, Holden LK, Skinner MW, Tobey EA, Peterson A, Gaggl W, et al. Recognition of speech presented at soft to loud levels by adult cochlear implant recipients of three cochlear implant systems. Ear Hear, 2004, 25(4), 375-87.Abstract

Firszt JB, Gaggl W, Runge-Samuelson CL, Burg LS, Wackym PA. Auditory sensitivity in children using the auditory steady-state response. Arch Otolaryngol Head Neck Surg, 2004, 130(5), 536-40.Abstract

Firszt JB, Wackym PA, Gaggl W, Burg LS, Reeder RM. Electrically evoked auditory brain stem responses for lateral and medial placement of the Clarion HiFocus electrode. Ear Hear. 2003, 24(2), 184-90.Abstract

Lasota KJ, Ulmer JL, Firszt JB, Biswal BB, Daniels DL, Prost RW. Intensity-dependent activation of the primary auditory cortex in functional magnetic resonance imaging. J Comput Assist Tomogr, 2003, 27(2), 213-8.Abstract

Firszt JB, Chambers RD, Kraus, Reeder RM. Neurophysiology of cochlear implant users I: effects of stimulus current level and electrode site on the electrical ABR, MLR, and N1-P2 response. Ear Hear, 2002, 23(6), 502-15.Abstract

Firszt JB, Chambers, Rd, Kraus N. Neurophysiology of cochlear implant users II: comparison among speech perception, dynamic range, and physiological measures. Ear Hear, 2002, 23(6), 516-31.Abstract

Holden LK, Skinner MW, Holden TA, Demorest ME. Effects of stimulation rate with the Nucleus 24 ACE speech coding strategy. Ear Hear, 2002, 23(5), 463-76.Abstract

Novak MA, Firszt JB, Rotz LA, Hammes D, Reeder R, Willis M. Cochlear implants in infants and toddlers. Ann Otol Rhinol Laryngol Suppl, 2000,185, 46-9.Abstract

Firszt JB, Rotz LA, Chambers RD, Novak MA. Electrically evoked potentials recorded in adult and pediatric CLARION implant users. Ann Otol Rhinol Laryngol Suppl, 1999, 177, 58-63.Abstract

Abbas PJ, Brown CJ, Shallop JK, Firszt JB, Hughes ML, Hong SH, et al. Summary of results using the nucleus CI24M implant to record the electrically evoked compound action potential. Ear Hear, 1999, 20(1), 45-59.Abstract

Holden LK, Skinner MW, Holden TA. Speech recognition with the MPEAK and SPEAK speech-coding strategies of the Nucleus cochlear implant.Otolaryngol Head Neck Surg, 1997, 116(2),163-7.Abstract

Holden LK, Skinner MW, Holden TA, Binzer SM. Comparison of the Multipeak (MPEAK) and Spectral Peak (SPEAK) speech coding strategies of the Nucleus 22 channel cochlear implant system. Am J Audiol, 1995, 4, 49-54.

Our team

Learn more about our researchers, staff, collaborators and lab alumni. 

Meet our team »

Contact Us

Phone: 314-747-0882 (8:00 am – 5:00 pm CST) 
Voice messages can be left after-hours

Email: firsztlab@ent.wustl.edu


Our lab is in Suite 1201 of the McMillan Building, located at 517 S. Euclid Avenue on the Washington University School of Medicine campus. 

Directions to the Firszt lab »

Directions to the Adult Cochlear Implant Program »

Mailing Address

Firszt Laboratory
Washington University School of Medicine
660 S. Euclid Ave., CB 8115
St. Louis, MO 63110