Otoacoustic Emissions Across The Lifespan (.15 CEUs)
Recorded On: 12/03/2014
Duration: 90 Minutes
Presenter: Sumitrajit Dhar, PhD
Who Should Attend:
Audiologists, Students, Physicians
Program Focus: Knowledge
Upon completion, each participant in the eAudiology Web seminar will be able to:
1. Identify cellular and molecular mechanisms responsible for distortion product otoacoustic emission generation.
2. Assess the specific effects of different cochlear pathologies on otoacoustic emissions.
3. Identify recording parameters that can be altered for specific clinical applications of otoacoustic emissions.
Otoacoustic emissions are sounds generated in the ear and have long been accepted to be an outcome of the amplification process in the cochlea. However, the cellular mechanisms responsible for their generation, their modulation by efferent input, and possible modes of their backward propagation to the ear canal are still being debated. Current knowledge in these domains will launch our discussion about these faint sounds generated in the inner ear.
Significant advances have recently been achieved in delivering accurate signals to the human ear canal for the evaluation of the entire hearing range up to 20 kHz. These methods are currently being leveraged to evaluate hearing thresholds and otoacoustic emissions across this wide frequency range. The effect of age on these estimates of auditory function are revealing trends in aging not evident before. In this eAudiology Web seminar, the use of objective measures in detecting early signs of aging and chemotoxicity will be discussed from dual perspectives. Results from a large-scale study will be used to trace the trajectory of otoacoustic emissions across a significant portion of the human lifespan. In parallel, individual case studies will be used to illustrate the power of stable measurements in tracking auditory function in individuals.
Sumitrajit (Sumit) Dhar, PhD is a Professor of Audiology and Hearing Science at Northwestern University. Sumit trained in Audiology and Hearing Science at the University of Mumbai, Utah State University, and Purdue University. His laboratory works on the basic science and applications of otoacoustic emissions. The Dhar lab has made contributions to the understanding of the generation mechanisms of otoacoustic emissions, especially distortion product otoacoustic emissions. Current research in the laboratory continues in this area with additional efforts to apply any understanding to the development of clinical tools. These tools are developed with a particular interest in early and accurate detection of cochlear pathologies. Work in the Dhar laboratory is supported by the National Institutes of Health of the United States of America, The Knowles Hearing Center at Northwestern University, and various private foundations.