This book describes current information about the three areas mentioned in the title: neuronal migration and development, degenerative brain diseases, and neural plasticity and regeneration. The chapters in the first section of the book examine the cellular and molecular mechanisms by which neurons are generated from the ventricular zone in the forebrain and migrate to their destinations in the cerebral cortex. This description of cortical development also includes discussions of the Cajal-Retzius cell. Another chapter provides insight about the development of another forebrain region, the hypothalamus. The remaining chapters of the first section examine the clinical relevance of brain development in certain disease states in humans. The second section begins with details about the dopaminergic neurons in the substantia niger and their loss in Parkinson's disease. Two subsequent chapters describe changes in brain aging, including changes in the numbers of myelinated axons. Other chapters in this section describe important cellular and molecular changes found in Alzheimer's disease and human epilepsy. The last section begins with a chapter on how the brain's own stem cells provide newly generated neurons to the hippocampal dentate gyrus and how these neurons become integrated into neural circuitry. Then two chapters examine some of the neuroplastic changes that take place in motor and sensory cortices of awake behaving primates. The concluding two chapters address the issue of regeneration in the injured spinal cord and the factors that may contribute to its success.