The term descending division of the paraventricular nucleus refers to one of three divisions of the paraventricular nucleus of the hypothalamus as defined by multiple methods in the rat ( Swanson-2004 ). It is located in the medial zone of the anterior hypothalamic region, caudal to the anterior hypothalamic nucleus and rostral to the ventromedial nucleus of the hypothalamus ( Swanson-2000 ). The descending division is further divided into four parts: the ventromedial parvicellular zone of the paraventricular nucleus, the dorsal parvicellular part of the paraventricular nucleus, the lateral parvicellular part of the paraventricular nucleus, and the fornical part of the paraventricular nucleus. Functionally it is part of the behavior control column of the subcortical motor system. The other divisions are the neuroendocrine motor zone and the somatic motoneuron pools of the paraventricular nucleus of the hypothalamus ( Swanson-2004 ).