Cochlear implant (CI) users who are 65 years or older typically show poorer speech perception performance than younger adult CI users, especially in competing background noise. The underlying mechanisms remain unclear. Whereas declined cognitive function has been proposed as the major factor, deteriorations in the auditory system have also been suggested to be the primary reason. As a result, there is no robust indicator for optimizing programming settings or habilitation strategies for older implanted patients. The long-term goal of this research is to better understand the neurophysiologic basis of speech perception deficits in older (≥ 65 years) CI users. As the first step to achieve this long-term goal, this study is designed to better understand underlying neurophysiological mechanisms of speech perception deficits in older CI users. Older listeners are known to have temporal processing deficits, and temporal cues are particularly important for discriminating speech in CI users. Therefore, the proposed study will focus on comparing peripheral and central auditory neural encoding of, and perceptual sensitivity to, temporal envelope cues between younger and older adult CI users. 

Cochlear nerve deficiency (CND) refers to a small or absent cochlear nerve (CN) as revealed by high-resolution magnetic resonance imaging. Cochlear implantation has been used as a treatment option for children with CND for nearly two decades. Due to the lack of understanding of how electrical stimulation is encoded and processed in their auditory system, there is still no evidenced-based clinical practice for managing this unique patient population. To further complicate matters, more than half of children with CND cannot provide reliable behavioral responses despite their age due to severe comorbidities. As a result, clinicians often use a combined “one-size-fits-all” and “try-and-see” approach to program cochlear implant (CI) speech processors for children with CND. This practice typically results in stimulating all intra-cochlear CI electrodes with similar programming parameters. However, recent work from our lab showed that the likelihood of measuring CN neural responses in children with CND reduced as the stimulating CI electrode site moved from the base to the apex of the cochlea. This unique response-deterioration pattern is not observed in children with normal-sized CNs. In addition, our compiling preliminary data show that information transmitted by CI electrodes with no measurable CN response is only adequate for auditory detection but not sufficient for auditory discrimination, which explains why the majority of children with CND do not make satisfactory progress in speech and language development despite good auditory detection thresholds with their CIs. These new findings suggest that the current clinical practice is unlikely to provide appropriate CI programming settings for this unique patient population. Therefore, there is an urgent need to develop objective clinical tools for optimizing CI settings for individual children with CND. Our long-term goals are 1) to understand neural encoding and processing of electrical stimulation in children with CND, and 2) to develop an effective, evidence-based clinical practice for managing this unique patient population.  As the first step toward these long-term goals, this study aims to better understand neural encoding and processing of electrical stimulation in both the CN and the central auditory system in implanted children with CND. 

Title: Neural encoding and auditory perception in cochlear implant users
Dates: 7/1/2017 – 6/30-2022
Name of agency: NIDCD and NIGMS
Role: Principal Investigator 
Award number: 1 R01 DC016038
Title: Neural encoding and auditory processing in pediatric cochlear implant users
Dates: 4/1/2019 – 3/30-2024
Name of agency: NIDCD 
Role: Principal Investigator 
Award number: 1 R01 DC017846

1. Teagle*, H.F.B., Henderson, L., He, S., Ewend, M.G., and Buchman*, C.A. (2018). Pediatric auditory brainstem implantation: surgical, electrophysiological and behavioral outcomes. Ear and Hearing, 39, 326-336. 

 

3. He*, S., Teagle, H.F.B., McFayden, T.C., Ewend, M., Henderson, L., He, N., and Buchman, C.A. (2018). Longitudinal changes in electrically evoked auditory event-related potentials in children with auditory brainstem implants: preliminary results recorded over three years. Ear and Hearing, 39, 318-325. 

4. He*, S., Shahsavarani, B.S., McFayden, T.C., Wang, H.B., Gill, K.E., Xu, L., Chao, X.H., Luo, J.F., and Wang, R.J. (2018). Responsiveness of the electrically stimulated auditory nerve in children with cochlear nerve deficiency. Ear and Hearing, 39, 238-250. 

5. He*, S., Teagle, H.F.B., and Buchman, C.A. (2017). The electrically evoked compound action potential: from laboratory to clinic. Frontiers in Neuroscience, June 23, 11: 339.  

6. He*, S., McFayden, T.C., Teagle, H.F.B., Ewend, M., Henderson, L., and Buchman, C.A. (2016). Electrically evoked auditory event-related responses in patients with auditory brainstem implants: morphological characteristics, test-retest reliability, effects of stimulation level and association with auditory detection. Ear and Hearing, 37, 634-649. 

7. He*, S., Abbas, P.J., Doyle, D.V., McFayden, T.C., and Mulherin, S. (2016). Temporal response properties of the auditory nerve in children with auditory neuropathy spectrum disorder and children with sensorineural hearing loss. Ear and Hearing, 37, 397-411. 

8. He*, S., Teagle, H.F.B., Ewend, M., Henderson, L., and Buchman, C.A. (2015). The electrically evoked cortical auditory event-related potential in children with auditory brainstem implant. Ear and Hearing, 36, 377-379. 

9. He*, S., Grose, J.H., Teagle, H.F.B., Woodard, J., Park, L.R., Hatch, D.R., Roush, P., and Buchman, C.A. (2015). Acoustically evoked auditory change complex in children with auditory neuropathy spectrum disorder: a potential objective tool for identifying cochlear implant candidates. Ear and Hearing, 36, 289-301. 

10. He*, S., Grose, J.H., Teagle, H.F.B., and Buchman, C.A. (2014). Objective measures of electrode discrimination with the electrically evoked auditory change complex and speech perception abilities in children with auditory neuropathy spectrum disorder. Ear and Hearing, 35, e63-74. 

Professor, 2018 - Current
Department of Otolaryngology - Head and Neck Surgery
The Ohio State University College of Medicine, Columbus, Ohio

Ear and Hearing 2018 Editor’s Award Nominee for Outstanding Contribution to the Literature on Hearing and Balance  

Auditory Neuropathy Spectrum Disorder 2014 Award, 8th International Symposium on Objective Measures in Auditory Implants

New Investigator Award, 8th International Symposium on Objective Measures in Auditory Implants 2014

Junior Faculty Career Development Award, UNC-Chapel Hill, 2014

Eunice Beam WISE Travel Award, University of Iowa, 2008

Graduate Student Senate Travel Funds Award, University of Iowa, 2008

Research and Teaching Assistantship, University of Iowa, 2003-2008  

NIH funded Student Travel Award, Conference on Implanted Auditory Prostheses, 2007 

Scholarship, Communication Sciences and Disorders Summer Institute, 2007

NIH Funded Student Travel Award, American Auditory Society, 2005

Teaching Activities 

• Instructor, University of North Carolina at Chapel Hill

               Auditory Evoked Potential II (Fall, 2009, 2010, 2011)

   

• Teaching Assistant, University of Iowa

   Introduction of Hearing Science (Fall, 2006, 2007)

               Basic Acoustics for Speech & Hearing (Spring, 2006, 2007)

   

• Teaching Assistant, Northwestern University

  Aural Rehabilitation (Spring, 2002).        

• Laboratory Instructor, Shandong Medical University

      Clinical Diagnosis (Spring, 1999, 2000, 2001)

Mentoring

Ph.D Student Advised

Xiuhua Chao (exchange Ph.D candidate from Shandong University)

Medical Students Advised (Including Medical Residents)

Anna X.Z. Hang

Paola Lopomo

AuD Student Advised

Heather Strader

Alexandria Gary

Danielle M. Verilli

Katherine Gill

Undergraduate Student Advised

Nancy He

Travis Warren

Jared Beckham

Stephen Mulherin