||This article may be too technical for most readers to understand. (November 2016) (Learn how and when to remove this template message)|
Mesial aspect of a brain sectioned in the median sagittal plane.
|Anatomical terms of neuroanatomy|
The diencephalon is one of the main vesicles of the brain formed during embryogenesis. During the third week of development a neural tube is created from the ectoderm - one of the three primary germ layers. The tube forms three main vesicles during the third week of development - the prosencephalon, the mesencephalon and the rhombencephlaon. The prosencephlon gradually divides into the telencephalon and the diencephalon.
The diencephalon consists of the following structures:
- Anterior and Posterior Paraventricular nuclei
- Medial and lateral Habenular nuclei
- Stria medullaris thalami
- Posterior commissure
- Pineal body
The optic nerve (CNII) attaches to the diencephalon. The optic nerve is a sensory (afferent) nerve responsible for vision; it runs from the eye through the optic canal in the skull and attaches to the diencephalon. The retina itself is derived from the optic cup, a part of the embryonic diencephalon.
The diencephalon is the region of the embryonic vertebrate neural tube that gives rise to anteriorforebrain structures including the thalamus, hypothalamus, posterior portion of the pituitary gland, and pineal gland. The hypothalamus performs numerous vital functions, most of which relating directly or indirectly to the regulation of visceral activities by way of other brain regions and the autonomic nervous system.