Hypothalamus

http://www.semanticweb.org/rjyy/ontologies/2015/5/ESSO#Hypothalamus

Hypothalamus

Trancred 2005 The Hypothalamus is involved in the maintenance of homeostasis, the regulation of feeding, drinking, and sexual activity, circadian rhythms and emotional expression. Structures: Arcuate Nucleus Diencephalon Hypophysis Hypothalamic Sulcus Hypothalamus Hypothalamus - Connections Hypothalamus - Nuclei Lamina Terminalis Mammillary Body Neurohypophysis Optic Tract Supraoptic Nucleus Thalamus Third Ventricle Information: The hypothalamus is a small region (approximately 4g in weight) which occupies the ventral part of the diencephalon, separated from the thalamus by the hypothalamic sulcus. Its importance is disproportionate in comparison with its small size. Its functions are associated with the maintenance of homeostasis and with the survival of the species (eg. feeding, drinking, reproduction). The hypothalamus surrounds the floor and lower lateral sides of the third ventricle. It extends anteriorly as far as the lamina terminalis and caudally to the posterior edge of the mammillary bodies. It can be seen on the ventral surface of the brain behind the optic chiasm and medial to the optic tracts. The region bounded by the optic chiasm and tracts and the mammillary bodies is known as the tuber cinereum. The median eminence, a swelling in the anterior part of the tuber cinereum just behind the optic tracts gives rise to the infundibular stem (infundibulum) which expands to form the infundibular process. Together the median eminence and the infundibular stem and process are called the neurohypophysis. The neurohypophysis constitutes the posterior part of the hypophysis (also known as the pituitary gland). The fornix passes through the hypothalamus in an anteroposterior direction towards the mammillary body and in so-doing, divides the hypothalamus into medial and lateral parts. The lateral part contains fibre tracts passing through plus some poorly defined nuclei which are collectively referred to as the lateral nuclei. The medial part can be further subdivided into 4 regions: (i) Preoptic region - anterior to the optic chiasm, adjacent to lamina terminalis. coantains the preoptic nucleus (ii) Suprachiasmatic region - dorsal to the optic chiasm. Contains supraoptic,suprachiasmatic, paraventricular and anterior nuclei. (iii) Tuberal region - dorsal to the tuber cinereum. Contains the arcuate, dorsomedian and ventromedian nuclei. (iv) Posterior (mammillary) region - contains the posterior nucleus and the mammillary body.

http://www.semanticweb.org/rjyy/ontologies/2015/5/ESSO#Brain_Structure