ABSTRACT
This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book begins by describing the modern definitions of chronic fatigue, fibromyalgia, irritable bowel, premenstrual dysphoria, and postcombat ailments and the way in which these entities have evolved into a tightly knit family of self-standing syndromes with a common core of somatic symptoms. It presents the frequency of psychiatric disorders in functional syndromes and analyzes the correlation between the burden of psychopathology and the physical features of these illnesses. The book shows that chronic fatigue syndrome, fibromyalgia, irritable bowel syndrome, premenstrual syndrome, and Gulf War illness are overlapping conditions with numerous medically unexplained complaints. It demonstrates that functional syndromes are not atypical manifestations of mood or anxiety disorders. Their psychopathology centers on production of somatic and psychological symptoms as expressions of neuroticism, harm avoidance, sexual victimization, and maladaptive coping.
