Book excerpt: Sleep and Affect: Assessment, Theory, and Clinical Implications synthesizes affective neuroscience research as it relates to sleep psychology and medicine. Evidence is provided that normal sleep plays an emotional regulatory role in healthy humans. The book investigates interactions of sleep with both negative and positive emotions, along with their clinical implications. Sleep research is discussed from a neurobiological, cognitive, and behavioral approach. Sleep and emotions are explored across the spectrum of mental health from normal mood and sleep to the pathological extremes. The book, additionally, offers researchers a guide to methods and research design for studying sleep and affect. This book will be of use to sleep researchers, affective neuroscientists, and clinical psychologists in order to better understand the impact of emotion on sleep as well as the effect of sleep on physical and mental well-being. - Contains neurobiological, cognitive, and behavioral approaches - Explains methods for examining sleep and affect - Summarizes research on sleep and specific affect states - Translates research for clinical use in treating disorders