Arthur N. Popper – författare

Sounds that are actually produced by healthy ears allow researchers and clinicians to study hearing and cochlear function noninvasively in both animals and humans. This book presents the first serious review of the biological basis of these otoacoustic emissions. Active processes, such as those in hair cells that produce emissions, represent a burgeoning and important area of sensory research. By providing a basis for understanding how and why otoacoustic emissions testing works through a basic understanding of general hearing processes, this volume will also interest clinicians, particularly otolaryngologists and audiologists.

This volume brings together noted scientists who study presbycusis from the perspective of complementary disciplines, for a review of the current state of knowledge on the aging auditory system. Age-related hearing loss (ARHL) is one of the top three most common chronic health conditions affecting individuals aged 65 years and older. The high prevalence of age-related hearing loss compels audiologists, otolaryngologists, and auditory neuroscientists alike to understand the neural, genetic and molecular mechanisms underlying this disorder. A comprehensive understanding of these factors is needed so that effective prevention, intervention, and rehabilitative strategies can be developed to ameliorate the myriad of behavioral manifestations.

Loudness is the primary psychological correlate of intensity. When the intensity of a sound increases, loudness increases. However, there exists no simple one-to-one correspondence between loudness and intensity; loudness can be changed by modifying the frequency or the duration of the sound, or by adding background sounds. Loudness also changes with the listener’s cognitive state. Loudness provides a basic reference for graduate students, consultants, clinicians, and researchers with a focus on recent discoveries. The book begins with an overview of the conceptual thinking related to the study of loudness, addresses issues related to its measurement, and later discusses the physiological effects of loud sounds, reaction times and electrophysiological measures that correlate with loudness. Loudness in the laboratory, loudness of steady-state sounds and the loudness of time-varying sounds are also covered, as are hearing loss and models. 

Efferent sensory systems have emerged as major components of processing by the central nervous system. Whereas the afferent sensory systems bring environmental information into the brain, efferent systems function to monitor, sharpen, and attend selectively to certain stimuli while ignoring others. This ability of the brain to implement these functions enables the organism to make fine discriminations and to respond appropriately to environmental conditions so that survival is enhanced. Our focus will be on auditory and vestibular efferents, topics linked together by the inner ear connection.

The biological utility of the efferent system is striking. How it functions is less well understood, and with each new discovery, more questions arise. The book that is proposed here reflects our vision to share what is known on the topic by authors who actually have made the observations.

 Synaptic Mechanisms in the Auditory System will provide a basic reference for students, clinicians, and researchers on how synapses in the auditory system function to encode acoustic signals. These mechanisms are the groundwork for all auditory processing, and understanding them requires knowledge of the microphysiology of synapses, cellular biophysics, receptor pharmacology, and an appreciation for what these synapses must do for a living, what unique jobs they carry out.

Exposure to loud noise continues to be the largest cause of hearing loss in the adult population. The problem of NIHL impacts a number of disciplines. US standards for permissible noise exposure were originally published in 1968 and remain largely unchanged today. Indeed, permissible noise exposure for US personnel is significantly greater than that allowed in numerous other countries, including for example, Canada, China, Brazil, Mexico, and the European Union. However, there have been a number of discoveries and advances that have increased our understanding of the mechanisms of NIHL. These advances have the potential to impact how NIHL can be prevented and how our noise standards can be made more appropriate.

This volume will provide an important contemporary reference on hearing development and will lead to new ways of thinking about hearing in children and about remediation for children with hearing loss. Much of the material in this volume will document that a different model of hearing is needed to understand hearing during development. The book is expected to spur research in auditory development and in its application to pediatric audiology.