Region of the hypothalamus adjacent to the third ventricle with corticotropin-releasing-factor (CRF)-containing neurons. It contains three main types of neurons: magnocellular, parvocellular, and long-projecting neurons. These neurons secrete CRF into the portal system via the capillaries of the median eminence, regulating adrenocorticotropic hormone (ACTH) secretion. The region is also important for regulating energy balance and various endocrine functions.