Epithalamus

The epithalamus (pl.: epithalami) is a posterior (dorsal) segment of the diencephalon. The epithalamus includes the habenular nuclei, the stria medullaris, the anterior and posterior paraventricular nuclei, the posterior commissure, and the pineal gland. The function of the epithalamus is to connect the limbic system to other parts of the brain. The epithalamus also serves as a connecting point for the dorsal diencephalic conduction system, which is responsible for carrying information from the limbic forebrain to limbic midbrain structures. Some functions of its components include the secretion of melatonin from the pineal gland (circadian rhythms), regulation of motor pathways and emotions, and how energy is conserved in the body. A study has shown that the lateral habenula, in the epithalamus, produces spontaneous theta oscillatory activity that was correlated with theta oscillation in the hippocampus. The same study also found that the increase in theta waves in both lateral habenula and hippocampus was correlated with increased memory performance in rats. This suggests that the lateral habenula has an interaction with the hippocampus that is involved in hippocampus-dependent spatial information processing. The epithalamus is a tiny structure that comprises the habenular trigone, the pineal gland, and the habenular commissure. It is wired with the limbic system and basal ganglia.