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The dorsal posterior subdivision of the diencephalon. The epithalamus is generally considered to include the habenular nuclei (HABENULA) and associated fiber bundles, the PINEAL BODY, and the epithelial roof of the third ventricle. The anterior and posterior paraventricular nuclei of the thalamus are included with the THALAMIC NUCLEI although they develop from the same pronuclear mass as the epithalamic nuclei and are sometimes considered part of the epithalamus.

The trigonum habenulae, the pineal body and the posterior commissure of the brain.

[Greek] Part of thalamencephalon, comprising trigonum habenulae, pineal body, and posterior commissure.

The posterior portion of the optic thalamus. [Gr.]