We invite you to join us for our final colloquium of 2024 with Dr. Navid Shahnaz and Dr. Valter Ciocca.
TITLE:
A simulation approach based on Bayesian multilevel regression for the estimation of population Reference Equivalent Threshold Sound Pressure Levels at conventional and extended High Frequencies in Young Adult
ABSTRACT:
Objectives:
This study aimed to establish the distributional properties of hearing thresholds in otologically normal young adults, measured in Reference Equivalent Threshold Sound Pressure Levels (RETSPLs) across conventional and extended high frequencies (EHFs). Additionally, the study sought to estimate hearing threshold differences by ear, gender, and ethnicity.
Design:
RETSPLs were obtained using an adaptive procedure with the Sennheiser HDA-200 earphone. A Bayesian multilevel distributional regression model was applied to thresholds, with its posterior generating threshold estimates for both ears and each frequency in 18,000 simulated participants.
Study Sample:
The study included a non-random sample of 18-36-year-old Caucasian and Asian participants with normal hearing (≤ 20 dB HL) at conventional frequencies. Thresholds were measured for each frequency in 223 ears from 65 Caucasian and 61 Chinese participants.
Results:
Simulated thresholds at conventional and EHFs aligned closely with ISO, ANSI standards, and other studies. No specific norms are recommended based on gender, ethnicity, or ear.
Conclusions:
The findings suggest that using a fixed 20 dB HL cutoff may overestimate typical hearing thresholds at conventional frequencies and underestimate at EHFs. This study provides preliminary data on the distributional properties of typical hearing thresholds in young adults from 250 to 16,000 Hz.
BIOS:
Dr. Navid Shahnaz is currently an Associate Professor of Audiology in the School of Audiology & Speech Sciences at the University of British Columbia (UBC), where he has been a faculty member since July 2002. He has been a Speech-Language and Audiology Canada (SAC) certified member since November 1995. He was a member of the national (CASLPA) Audiology Examination Committee between 2002 and 2008, and a member of the CASLPA Board of Governors (2011-2014), where he was the representative of the Canadian Council of University Programs in Communication Sciences and Disorders. His main area of research interest includes multi-frequency tympanometry, Wideband Acoustic Immittance, otoacoustic emission, and acoustic reflex studies in adults, children, and infants. His new research interests also focus on the assessment of the balance systems using vestibular evoked myogenic potentials, and the development of test batteries for assessment of the silent (hidden) hearing loss.
Dr. Valter Ciocca completed his undergraduate studies in Experimental Psychology at the University of Padua (Italy). He subsequently went to McGill University, where he completed his Ph.D. in the Department of Psychology under the guidance of Albert Bregman, with a thesis on the application of auditory scene analysis principles to speech perception. He then continued his research training with Chris Darwin at the University of Sussex, where he investigated the effects of auditory grouping on pitch perception. In 1992, he joined the Department of Speech and Hearing Sciences at Hong Kong University, where he applied his knowledge of auditory perception and speech science to the study of Cantonese speech and of lexical tones. At Hong Kong University he extended his research to the study of populations of listeners and speakers with communication disorders (individuals with cerebral palsy and hearing impairments, including cochlear implant users), as well as adults with normal communication abilities and typically developing children. He joined the School of Audiology and Speech Sciences at UBC in 2007 as the School’s Director, a role he continued in until 2017.
We look forward to seeing you on November 20th at 12:30pm! If you plan to join us virtually, please click here to RSVP for the Zoom session.