This volume details the essential role of the spiral ganglion neurons. A comprehensive review about the spiral ganglion neurons is important for researchers not only in the inner ear field but also in development, neuroscience, biophysics as well as neural networks researchers. The chapters are authored by leading researchers in the field. Connecting the Inner Ear to the Central Auditory System: Molecular Development and Characteristics of the Primary Auditory Neurons and Their Network by Alain Dabdoub and Bernd Fritzsch Early Development of the Spiral Ganglion by Lisa V. Goodrich Neurotrophic Factor Function during Ear Development: Expression Changes Define Critical Phases for Neuronal Viability by Bernd Fritzsch, Jennifer Kersigo, Tian Yang, Israt Jahan, and Ning Pan The Electrophysiological Signature of Spiral Ganglion Neurons by Robin L. Davis and Robert A. Crozier The Ribbon Synapse Between Type I Spiral Ganglion Neurons and Inner Hair Cells by Mark A. Rutherford and Tobias Moser Central Projections of Spiral Ganglion Neurons by Michael A. Muniak, Catherine J. Connelly, Kirupa Suthakar, Giedre Milinkeviciute, Femi E. Ayeni, and David K. Ryugo The Spiral Ganglion in an Out-of-Body Experience: a Brief History of In Vitro Studies of the Spiral Ganglion by Steven H. Green, Erin M. Bailey, Jonathan C. Kopelovich, and Marlan R. Hansen Loss, Degeneration, and Preservation of the Spiral Ganglion Neurons and Their Processes by Hainan Lang Stem Cells for the Replacement of Auditory Neurons by Bryony A. Nayagam and Albert S. B. Edge About the Editors: Alain Dabdoub is Research  Director of The Sunnybrook Hearing Regeneration Initiative, Sunnybrook Research Institute and an Assistant Professor in the Department of Otolaryngology – Head and Neck Surgery  at the University of Toronto Bernd Fritzsch is Chair of the Department of Biology and Co-Director of the Center on Aging and Aging Mind and Brain Initiative , University of Iowa, Iowa City Arthur N. Popper is Professor Emeritus and Research Professor in the Department of Biology at the University of Maryland, College Park. Richard R. Fay is Distinguished Research Professor of Psychology at Loyola University Chicago.