The epithalamus is a dorsal

Dorsum (biology)

In anatomy, the dorsum is the upper side of animals that typically run, fly, or swim in a horizontal position, and the back side of animals that walk upright. In vertebrates the dorsum contains the backbone. The term dorsal refers to anatomical structures that are either situated toward or grow...

 posterior segment of the diencephalon

Diencephalon

The diencephalon is the region of the vertebrate neural tube which gives rise to posterior forebrain structures. In development, the forebrain develops from the prosencephalon, the most anterior vesicle of the neural tube which later forms both the diencephalon and the...

 (a segment in the middle of the brain

Brain

The brain is the center of the nervous system in all vertebrate and most invertebrate animals—only a few primitive invertebrates such as sponges, jellyfish, sea squirts and starfishes do not have one. It is located in the head, usually close to primary sensory apparatus such as vision, hearing,...

 also containing the hypothalamus

Hypothalamus

The Hypothalamus is a portion of the brain that contains a number of small nuclei with a variety of functions...

 and the thalamus

Thalamus

The thalamus is a midline paired symmetrical structure within the brains of vertebrates, including humans. It is situated between the cerebral cortex and midbrain, both in terms of location and neurological connections...

) which includes the habenula

Habenula

In neuroanatomy, habenula originally denoted the stalk of the pineal gland , but gradually came to refer to a neighboring group of nerve cells with which the pineal gland was believed to be associated, the habenular nucleus...

, the stria medullaris

Stria medullaris

The stria medullaris, also known as stria medullaris thalami, is a fiber bundle containing efferent fibers from the septal nuclei, lateral preoptico-hypothalamic region, and anterior thalamic nuclei to the habenula...

 and the pineal body. Its function is the connection between the limbic system

Limbic system

The limbic system is a set of brain structures including the hippocampus, amygdala, anterior thalamic nuclei, septum, limbic cortex and fornix, which seemingly support a variety of functions including emotion, behavior, long term memory, and olfaction. The term "limbic" comes from the Latin...

 to other parts of the brain.

Functions

Some functions of its components include the secretion of melatonin

Melatonin

Melatonin , also known chemically as N-acetyl-5-methoxytryptamine, is a naturally occurring compound found in animals, plants, and microbes...

 by the pineal gland (involved in circadian rhythms), and regulation of motor pathways and emotions. It is wired with the limbic system and basal ganglia.

Components

The epithalamus comprises the trigonum habenulæ, the pineal body, and the posterior commissure

Posterior commissure

The posterior commissure is a rounded band of white fibers crossing the middle line on the dorsal aspect of the upper end of the cerebral aqueduct. It is important in the bilateral pupillary light reflex....

.

External links

• Overview at University of Idaho
  University of Idaho
  The University of Idaho is the State of Idaho's flagship and oldest public university, located in the rural city of Moscow in Latah County in the northern portion of the state...
  
  
• http://isc.temple.edu/neuroanatomy/lab/atlas/pdhn/
• NIF Search - Epithalamus via the Neuroscience Information Framework
  Neuroscience Information Framework
  The Neuroscience Information Framework is a repository of global neuroscience web resources, including experimental, clinical, and translational neuroscience databases, knowledge bases, atlases, and genetic/genomic resources.-Description:...