The Fourth Edition of Yost's successful introductory book on hearing, this edition updates and expands the fundamental facts about hearing. Fundamentals of Hearing is still the only non-edited book that covers sound, auditory anatomy and physiology, and psychoacoustics and auditory perception in one book at an introductory level. An Instructor's Workbook contains 15 chapters, one for each in the textbook. Each chapter contains 12 problems and answers, suggested tracks form the ASA Audio CD-ROM (audio examples for understanding hearing provided by the Acoustical Society of America - this CD-ROM will not be included), suggestions for class exercises, and for some chapters, example figures and graphs. The CD-ROM provided with the Instructor's Workbook contains a copy of all the figures in the textbook, as well as text files that can be loaded into any spread sheet. These files contain the basic data and plots used in the book, a toolbox of MATLAB routines (a math program of Mathworks, Inc., used by many people who study all aspects of hearing), both MATLAB and executable Windows 95 programs for generating sounds, a simulation of measuring a neural tuning curve, and running psychophysical experiments for discrimination and detection of tones in noise (both diotic and dichotic). The key features include: approximately 25 per cent new information; a new chapter, The Abnormal Auditory System, which replaces the chapter on Noise; all figures redone; Instructor's Workbook and CD-ROM; and a Website, with a Hearing Tutorial based on the book.