Epithalamus

The epithalamus is a part of the midbrain ( diencephalon ). It lies dorsal to the thalamus in the III. Ventricle. For Epithalamus include:

• Pineal gland ( epiphysis, pineal, pineal gland )
• Habenula ( reins )
• Pretectal area
• Posterior commissure ( commissure epithalamic )

The pineal gland occupies an intermediate position between the central nervous system and the endocrine organs in the classification of the organs. It plays an important role in the control of circadian (day - night) and seasonal rhythms and is therefore also counted for photoneuroendokrinen system.

The Habenula are part of the olfactory system. Your cores ( habenular nuclei ) are switching station for trains that connect the olfactory bulb with the autonomic centers in the brainstem.

The pretectal area adjacent to the midbrain and contains the nuclei pretectales, who are responsible for the reflex constriction of the pupil when light falls. Since some of their efferent fibers of the posterior commissure to cross to the other side, always both pupils (see adaptation so-called consensual pupillary reflex (eye) ) constrict simultaneously.

The posterior commissure is a cross- connection of the superior colliculus ( in animals: rostral colliculus ) of the lamina tecti and is part of the visual pathway.