Efficient auditory processing requires the rapid integration of transient sensory inputs. This is exemplified in human speech perception, in which long stretches of a complex acoustic signal are typically processed accurately and essentially in real-time. Spoken language thus presents listeners’ auditory systems with a considerable challenge even when acoustic input is clear. However, auditory processing ability is frequently compromised due to congenital or acquired hearing loss, or altered through background noise or assistive devices such as cochlear implants. How does loss of sensory fidelity impact neural processing, efficiency, and health? How does this ultimately influence behavior? This Research Topic explores the neural consequences of hearing loss, including basic processing carried out in the auditory periphery, computations in subcortical nuclei and primary auditory cortex, and higher-level cognitive processes such as those involved in human speech perception. By pulling together data from a variety of disciplines and perspectives, we gain a more complete picture of the acute and chronic consequences of hearing loss for neural functioning.

Millions of Americans experience some degree of hearing loss. The Social Security Administration (SSA) operates programs that provide cash disability benefits to people with permanent impairments like hearing loss, if they can show that their impairments meet stringent SSA criteria and their earnings are below an SSA threshold. The National Research Council convened an expert committee at the request of the SSA to study the issues related to disability determination for people with hearing loss. This volume is the product of that study. Hearing Loss: Determining Eligibility for Social Security Benefits reviews current knowledge about hearing loss and its measurement and treatment, and provides an evaluation of the strengths and weaknesses of the current processes and criteria. It recommends changes to strengthen the disability determination process and ensure its reliability and fairness. The book addresses criteria for selection of pure tone and speech tests, guidelines for test administration, testing of hearing in noise, special issues related to testing children, and the difficulty of predicting work capacity from clinical hearing test results. It should be useful to audiologists, otolaryngologists, disability advocates, and others who are concerned with people who have hearing loss.

We live in an aging world. Illnesses that are prevalent and cause significant morbidity and mortality in older people will consume an increasing share of health care resources. One such illness is depression. This illness has a particularly devastating impact in the elderly because it is often undiagnosed or inadequately treated. Depression not only has a profound impact on quality of life but it is associated with an increased risk of mortality from suicide and vascular disease. In fact for every medical illness studied, e.g. heart disease, diabetes, cancer, individuals who are depressed have a worse prognosis. Research has illuminated the physiological and behavioral effects of depression that accounts for these poor outcomes. The deleterious relationship between depression and other illnesses has changed the concept of late-life depression from a "psychiatric disorder" that is diagnosed and treated by a psychiatrist to a common and serious disorder that is the responsibility of all physicians who care for patients over the age of 60. This is the first volume devoted to the epidemiology, phenomenology, psychobiology, treatment and consequences of late-life depression. Although much has been written about depressive disorders, the focus has been primarily on the illness as experienced in younger adults. The effects of aging on the brain, the physiological and behavioral consequences of recurrent depression, and the impact of other diseases common in the elderly, make late-life depression a distinct entity. There is a compelling need for a separate research program, specialized treatments, and a book dedicated to this disorder. This book will be invaluable to psychiatrists, gerontologists, clinical psychologists, social workers, students, trainees, and others who care for individuals over the age of sixty.

There has been substantial progress in understanding the contributions of the auditory forebrain to hearing, sound localization, communication, emotive behavior, and cognition. The Auditory Cortex covers the latest knowledge about the auditory forebrain, including the auditory cortex as well as the medial geniculate body in the thalamus. This book will cover all important aspects of the auditory forebrain organization and function, integrating the auditory thalamus and cortex into a smooth, coherent whole. Volume One covers basic auditory neuroscience. It complements The Auditory Cortex, Volume 2: Integrative Neuroscience, which takes a more applied/clinical perspective.

The field of Binaural Hearing involves studies of auditory perception, physiology, and modeling, including normal and abnormal aspects of the system. Binaural processes involved in both sound localization and speech unmasking have gained a broader interest and have received growing attention in the published literature. The field has undergone some significant changes. There is now a much richer understanding of the many aspects that comprising binaural processing, its role in development, and in success and limitations of hearing-aid and cochlear-implant users. The goal of this volume is to provide an up-to-date reference on the developments and novel ideas in the field of binaural hearing. The primary readership for the volume is expected to be academic specialists in the diverse fields that connect with psychoacoustics, neuroscience, engineering, psychology, audiology, and cochlear implants. This volume will serve as an important resource by way of introduction to the field, in particular for graduate students, postdoctoral scholars, the faculty who train them and clinicians.

The brain is the most complex organ in our body. Indeed, it is perhaps the most complex structure we have ever encountered in nature. Both structurally and functionally, there are many peculiarities that differentiate the brain from all other organs. The brain is our connection to the world around us and by governing nervous system and higher function, any disturbance induces severe neurological and psychiatric disorders that can have a devastating effect on quality of life. Our understanding of the physiology and biochemistry of the brain has improved dramatically in the last two decades. In particular, the critical role of cations, including magnesium, has become evident, even if incompletely understood at a mechanistic level. The exact role and regulation of magnesium, in particular, remains elusive, largely because intracellular levels are so difficult to routinely quantify. Nonetheless, the importance of magnesium to normal central nervous system activity is self-evident given the complicated homeostatic mechanisms that maintain the concentration of this cation within strict limits essential for normal physiology and metabolism. There is also considerable accumulating evidence to suggest alterations to some brain functions in both normal and pathological conditions may be linked to alterations in local magnesium concentration. This book, containing chapters written by some of the foremost experts in the field of magnesium research, brings together the latest in experimental and clinical magnesium research as it relates to the central nervous system. It offers a complete and updated view of magnesiums involvement in central nervous system function and in so doing, brings together two main pillars of contemporary neuroscience research, namely providing an explanation for the molecular mechanisms involved in brain function, and emphasizing the connections between the molecular changes and behavior. It is the untiring efforts of those magnesium researchers who have dedicated their lives to unraveling the mysteries of magnesiums role in biological systems that has inspired the collation of this volume of work.

Since the first edition was published in 1998, considerable advances have been made in the fields of pitch perception and speech perception. In addition, there have been major changes in the way that hearing aids work, and the features they offer. This book will provide an understanding of the changes in perception that take place when a person has cochlear hearing loss so the reader understands not only what does happen, but why it happens. It interrelates physiological and perceptual data and presents both this and basic concepts in an integrated manner. The goal is to convey an understanding of the perceptual changes associated with cochlear hearing loss, of the difficulties faced by the hearing-impaired person, and the limitations of current hearing aids.