Compression for clinicians / Theodore H. Venema.

Includes bibliographical references and index.

1. THE COCHLEA, HAIR CELLS, AND COMPRESSION:- Introduction--A sketch of cochlear anatomy and Physiology--Inner and outer hair cells: Structure and function--The passive, asymmetrical traveling wave--OHCs and active traveling wave--Damaged hair cells and hearing loss--Presbycusis: The most common type of hearing loss--Hearing aids for the damaged cochlea--Summary--Review questions--Recommended readings--References--2. THE COCHLEAR DEAD SPOT CONCEPT: IMPLICATIONS FOR HEARING AID FITTINGS:- Introduction--What are cochlear dead regions?--The TENT test CD: Description, Procedure, and Rationale--Hearing losses commmonly associated with cochlear dead regions--The ten test and moderate reverse SNHL--The TEN test and severe, precipitous high-frequency SNHL--The cookie-biteSNHL--The TEN Test: Old version in dB SPL versus Audiometric Testing in dB HL--Case studies with the TEN test--Case 1: A subject with normal hearing--Case 2: A subject with sloping high-frequency SNHL--Case 3: A subject with a severe-profound mid-high-frequency SNHL--Dead regions and implications for amplification--Perceptions of sounds within a dead hair cell region--A new version of the TEN Test--Summary--Review questions--Additional resource--Acknowledgement--References--3. WHY SO MANY DIFFERENT HEARING AID FITTING METHODS?:- Introduction--Lenses for the eye versus hearing aids for the ear--The audibility problem--The speech-in-noise problem--A short history of hearing aid technology--Linear hearing aids--A short history of linear - based fitting methods--Can\'t we just mirror the audiogram with Gain?--Lybarger half-gain rule--Summary--Review questions--Recommended readings--References-- 4. COMPRESSION AND THE DSL AND NAL-NL1 FITTING METHODS:- Introduction--Loudness growth and consequences of a reduced dynamic range--Compression and normal loudness growth--DSL fitting method--Case 1: A subject with unusual cookie-bite Mild-to-Moderate SNHL--Case 2: A subject with a flat SNHL--The NAL-NL1 fitting method--DSL versus NAL-NL1: How do they compare?--Some reflections on fitting methods--Summary--Review questions--Recommended readings--references--5. THE MANY FACES OF COMPRESSION:- Introduction--A word about input/output graphs--Input compression versus output compression--Output compression--Input compression--Clinical uses of input and output compression--Compression controls: Conventional versus TK--Conventional compression control--TK control--Clinical uses of output limiting and TK compression controls--Output limiting compression versus wide dynamic range Compression (WDRC)--Output limiting compression--Wide dynamic range compression (WDRC)--Clinical applications of output limiting compression and WDRC--BILL and TILL: Two Types of WDRC-- Common clinical combinations of compression-- A compression combination for severe-to-profound hearing loss--A compression combination for mild-to-moderate hearing loss--Dynamic aspects of ompression--Peak detection--Automatic volume control--Syllabic compression--Adaptive compression--Average detection--Interaction between static and dynamic aspects of compression--Summary--Review Questions--Recommended readings--References--6. MULTI-CHANNEL PROGRAMMABLE HEARING AIDS:- Introduction--Programmable Hearing aids--Multichannel hearing aids--Summary--Review questions--Recommended readings--7. DIGITAL HEARING AIDS:- Introduction--Digital versus Analog--Open platform versus closed platform--In situ testing--Digital Architecture: Channels and Bands--Automatic feedback reduction--Digital combinations of compression--Dynamic compression characteristics in digital hearing aids--Adaptive dynamic range optimization (ADROtm)--expansion--Digital noise reduction (DNR) methods--Digital noise reduction (DNR) in digital hearing aids--Two examples of early digital hearing aids--Digital hearing aids: state of the art and the future--Summary--Review questions--Recommended readings--References--8. CLINICAL BENEFITS OF DIRECTIONAL MICROPHONES VERSUS DIGITAL NOISE REDUCTION:- Introduction--Directional Microphones--How Directional Microphones work--Directional microphones: How they are measured--The present and future for directional microphones--Digital Noise Reduction--Clinical benefits of DNR--Why are there no single-channel digital hearing aids offering DNR?--Directional Microphones and DNR as a team--Summary--Review questions--Recommended readings--References.

Explains signal compression concepts and how to apply them to selecting and fitting hearing aids. This book covers anatomic and physiologic description of the cochlea, providing an overview of hearing aid fitting methods, loudness growth functions, the many ways compression is incorporated in hearing aids, and more.