The International Summer School of Brain Research, on which this book is based, was organized by the Netherlands Institute for Brain research (NIBR), which has a rich history dating back to the beginning of the century.The focus of interest in this present volume of Progress in Brain Research are the few thousand neurons at the base of the hypothalamus that form the biological clock. Attention is focused on the mechanisms underlying the generation of circadian rhythmicity within our biological clock, which is still far from understood. Contributions originating from many disciplines give updates on the latest theories on the molecular and electrophysiological basis of the pacemaker mechanism, and the various approaches used in different species. Attention is also paid to the way the signal of the biological clock is transferred to the rest of the central nervous system. New data on the role of the suprachiasmatic nucleus and its impact on the functioning of the human being is presented. Altogether an excellent volume which will further the understanding of this elusive material.

With the invitation to edit this volume, I wanted to take the opportunity to assemble reviews on different aspects of circadian clocks and rhythms. Although most c- tributions in this volume focus on mammalian circadian clocks, the historical int- duction and comparative clocks section illustrate the importance of various other organisms in deciphering the mechanisms and principles of circadian biology. Circadian rhythms have been studied for centuries, but only recently, a mole- lar understanding of this process has emerged. This has taken research on circadian clocks from mystic phenomenology to a mechanistic level; chains of molecular events can describe phenomena with remarkable accuracy. Nevertheless, current models of the functioning of circadian clocks are still rudimentary. This is not due to the faultiness of discovered mechanisms, but due to the lack of undiscovered processes involved in contributing to circadian rhythmicity. We know for example, that the general circadian mechanism is not regulated equally in all tissues of m- mals. Hence, a lot still needs to be discovered to get a full understanding of cir- dian rhythms at the systems level. In this respect, technology has advanced at high speed in the last years and provided us with data illustrating the sheer complexity of regulation of physiological processes in organisms. To handle this information, computer aided integration of the results is of utmost importance in order to d- cover novel concepts that ultimately need to be tested experimentally.

One of the major breakthroughs of the last decade in the understanding of energy homeostasis is the identification of a reciprocal control between circadian rhythmicity and cellular metabolism. Circadian rhythmicity is a fundamental endogenous process of almost every organism living on Earth. For instance, the alternation of hunger and satiety is not continuous over 24 h, but is instead structured in time along the light/dark cycle. In mammals, the temporal organization of metabolism, physiology and behavior around 24 h is controlled by a network of multiple cellular clocks, synchronized via neuronal and hormonal signals by a master clock located in the suprachiasmatic nuclei of the hypothalamus. This central circadian conductor in the brain is mainly reset by ambient light perceived by the retina, while secondary circadian clocks in other brain areas and peripheral organs can be reset by meal timing. Chronic disruption of circadian rhythms, as seen in human shift-workers (up to 20% of the active population), has been associated with the development of a number of adverse mental and metabolic conditions. Understanding of the functional links between circadian desynchronization and overall health in animal models and humans, however, is still scarce. Interactions between circadian clocks and metabolism can occur at different levels: the molecular clockwork, internal synchronization via neuro-hormonal signals, or external synchronization via photic or feeding cues. This Research Topic comprises a number of reviews as well as research and methods articles that feature recent advancements in the mechanisms linking circadian clocks with energy metabolism, and the pathophysiological implications of these interactions for metabolic health.

This book focuses on the neuropsychopharmacology of serotonin and its role in sleep and wakefulness, presenting neurochemical, electrophysiological, and neuropharmacological approaches to understand the mechanisms of serotonin and related substances. Covering core and contemporary topics in the area, this volume is valuable for all researchers interested in interdisciplinary studies concerning drugs affecting the central nervous system.

While the first edition of the critically acclaimed and highly popular Circadian Physiologyoffered a concise but rigorous review of basic and applied research on circadian rhythms, this newest edition provides educators with the primary textbook they need to support a course on this cutting-edge topic. Maintaining the same accessible multidi

Addressed primarily to researchers of fish, but also of possible interest to researchers of biological rhythms in general, 19 papers from a workshop near Montreal, August 1991, discuss aspects of the biorhythms of fishes as they apply to aquaculture and to reactions to the pollution of natural habit

Kisspeptin has been shown to be both necessary and sufficient for activation of the reproductive axis, during puberty and later in adulthood. This makes kisspeptin a fundamental component of the reproductive axis. Kisspeptin has been deemed the single most potent stimulator of GnRH neurons yet known. The importance of kisspeptin has been documented in humans as well as non-human animal models, ranging from monkeys, sheep, and rodents to numerous fish species, thus signifying a highly conserved nature of its reproductive function. Importantly, kisspeptin neurons seem to mediate many of the regulatory effects of other signals, whether they are metabolic, circadian, hormonal, or stress. This places kisspeptin neurons in a unique position to be key nodal points and conduits for conveying numerous endogenous and exogenous signals to the reproductive axis.

From 11 to 15 July 1977 about 60 physiologists, endo crinologists, ecologists and other biologists from 14 countries convened at the University Montpellier for a symposium on Environmental Endocrinology. This meet ing was organized as a Satellite Symposium of the 27th International Congress of Physiological Sciences, Paris, 18-23 July 1977. This volume is a record of the com munications presented at the symposium. The objectives of the program were to examine the role of the endocrine system in a wide spectrum of adjustments and adaptations to changes in environmental conditions by various spe cies of animals, including man, and to promote an ex change of ideas among investigators who have approached these functions from diverse aspects. The diversity of the information and ideas communicated is great. Of necessity, they represent only an extremely modest se lection of the many facets of endocrine function in the interaction of animals with their environments. Be yond the usefulness of the communications individually, we hope that they collectively demonstrate the substan tial heuristic value of the concept of environmental endocrinology as it was perceived by the participants. We acknowledge gratefully the kindness and sympathy of Professor Jaques ROUZAUD, President of the University of Montpellier II, for his generous extension of the hospitality of the University to the Symposium. We are most grateful to Mrs. Monique VIEU who effected so well the secretarial organization of the Sympos.

Circadian rhythms, the biological oscillations based around our 24-hour clock, have a profound effect on human physiology and healthy cellular function. Circadian Rhythms: Health and Disease is a wide-ranging foundational text that provides students and researchers with valuable information on the molecular and genetic underpinnings of circadian rhythms and looks at the impacts of disruption in our biological clocks in health and disease. Circadian Rhythms opens with chapters that lay the fundamental groundwork on circadian rhythm biology. Section II looks at the impact of circadian rhythms on major organ systems. Section III then turns its focus to the central nervous system. The book then closes with a look at the role of biological rhythms in aging and neurodegeneration. Written in an accessible and informative style, Circadian Rhythms: Health and Disease,will be an invaluable resource and entry point into this fascinating interdisciplinary field that brings together aspects of neuroscience, cell and molecular biology, and physiology.

The purpose of this book is to present a focused approach to the pathophysiology, diagnosis, and management of the most common autonomic disorders that may present to the clinical neurologist. Autonomic Neurology is divided into 3 sections. The first section includes 5 chapters reviewing the anatomical and biochemical mechanisms of central and peripheral nervous system control of autonomic function, principles of autonomic pharmacology, and a clinical and laboratory approach to the diagnosis of autonomic disorders. The second section focuses on the pathophysiology and management of orthostatic hypotension, postural tachycardia, baroreflex failure; syncope, disorders of sweating, neurogenic bladder and sexual dysfunction, gastrointestinal dysmotility, and autonomic hyperactivity. The final section is devoted to specific autonomic disorders, including central neurodegenerative disorders; common peripheral neuropathies with prominent autonomic failure; painful small fiber neuropathies; autoimmune autonomic ganglionopathies and neuropathies; focal brain disorders; focal spinal cord disorders; and chronic pain disorders with autonomic manifestations. This book is the product of the extensive experience of its contributors in the evaluation and management of the many patients with autonomic symptoms who are referred for neurologic consultation at Mayo Clinic in Rochester, Minnesota. Autonomic Neurology focuses on clinical scenarios and presentation of clinical cases and includes several figures showing the results of normal and abnormal autonomic testing in typical conditions. Its abundance of tables summarizing the differential diagnosis, testing, and management of autonomic disorders also help set this book apart from other books focused on the autonomic nervous system.