SECTION 1 Introduction 1. Introduction: The anterior hypothalamus 2. History of hypothalamic research: "The spring of primitive existence 3. Anatomy and cytoarchitectonics of the human hypothalamus 4. Morphology and distribution of hypothalamic peptidergic systems 5. MRI maps, segregation, and white matter connectivity of the human hypothalamus in health 6. Magnetic resonance imaging of the hypothalamo-pituitary region 7. Resting-state functional connectivity of the human hypothalamus 8. Neurogenesis in the adult hypothalamus: A distinct form of structural plasticity involved in metabolic and circadian regulation, with potential relevance for human pathophysiology 9. Matching of the postmortem hypothalamus from patients and controls SECTION 2 The basal forebrain cholinergic system 10. Spatial topography of the basal forebrain cholinergic projections: Organization and vulnerability to degeneration 11. The diagonal band of Broca in health and disease 12. Nucleus basalis of Meynert degeneration predicts cognitive impairment in Parkinson's disease 13. Enlargement of early endosomes and traffic jam in basal forebrain cholinergic neurons in Alzheimer's disease 14. Gene and cell therapy for the nucleus basalis of Meynert with NGF in Alzheimer's disease SECTION 3 The circadian system 15. The circadian system: From clocks to physiology 16. Development of the circadian system and relevance of periodic signals for neonatal development 17. Disrupted circadian rhythms and mental health 18. Diurnal and seasonal molecular rhythms in the human brain and their relation to Alzheimer disease 19. Circadian changes in Alzheimer's disease: Neurobiology, clinical problems, and therapeutic opportunities 20. The circadian system in Parkinson's disease, multiple system atrophy, and progressive supranuclear palsy 21. Retina and melanopsin neurons 22. Melatonin and the circadian system: Keys for health with a focus on sleep 23. Melatonin receptors, brain functions, and therapies 24. Chronotherapy 25. The use of melatonin to mitigate the adverse metabolic side effects of antipsychotics SECTION 4 Bed nucleus of the stria terminalis and the fear circuit 26. Chemoarchitecture of the bed nucleus of the stria terminalis: Neurophenotypic diversity and function 27. Functional anatomy of the bed nucleus of the stria terminalis-hypothalamus neural circuitry: Implications for valence surveillance, addiction, feeding, and social behaviors 28. Roles of the bed nucleus of the stria terminalis and amygdala in fear reactions SECTION 5 Preoptic area 29. The median preoptic nucleus: A major regulator of fluid, temperature, sleep, and cardiovascular homeostasis 30. The neuroendocrinology of the preoptic area in menopause: Symptoms and therapeutic strategies 31. The intermediate nucleus in humans: Cytoarchitecture, chemoarchitecture, and relation to sleep, sex, and Alzheimer disease