It is divided into four main structuresthe thalamus,hypothalamus, epithalamus, and subthalamus.
Structures that make up the diencephalon are also involved in regulating body temperature, appetite, and more.
Dysfunction of any of these crucial parts of the human brain can result in serious health conditions.
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It is part of the third ventricle of the brain.
Along with the cerebrum, the diencephalon is part of the forebrain.
Theoptic nerveconnects the eyes to several structures located within the diencephalon.
These bulbs sit atop the subthalamus and are also connected to the epithalamus.
The two parts of the thalamus are connected via the interthalamic adhesion.
Multiple nerve fibers connect the thalamus to the cerebral cortex.
The habenula are connected to the diencephalon by a group of nerve fibers called the habenular commissure.
The pineal gland is unpaired and approximately 5-7 millimeters (mm) in size.
Subthalamus
Ventral to the thalamus is the subthalamus.
Other important structures within the subthalamus include the zona incerta, the reticular nucleus, and the perigeniculate nucleus.
Hypothalamus
The hypothalamus is a very small cone-shaped structure that lies beneath the thalamus.
Despite its small size, it is one of the most important structures in the human brain.
Other adjacent structures include the mammillary bodies and theoptic chiasm.
The thalamus also receives sensory and motor signals from the body and relays this information to the cerebral cortex.
It plays a crucial role in regulating consciousness and alertness.
The epithalamus contains the pineal gland which secretesmelatonin.
Melatonin is responsible for the sleep-wake cycle (circadian rhythm) in humans.
Nerve pathways also connect the epithalamus with the limbic system and basal ganglia.
The subthalamus has different parts including:
The hypothalamus is known for maintaininghomeostasis.
Homeostasis is a state of balance, wellness ,or proper functioning in a sense.
It can be described as internal stability.
It regulates major hormones including oxytocin and antidiuretic hormone (ADH).
Signals coming from the hypothalamus cause other endocrine glands in the body to release vital hormones.
For example, it signals theadrenal glandsto release cortisone or thethyroid glandto release thyroid hormones.
They may include but are not limited to:
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Medicine LibreTexts.Epithalamus and pineal gland.
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Ilahi S, Beriwal N, Ilahi TB.Physiology, pineal gland.
Northwestern Medicine.Huntingtons disease linked to dysfunction of brain structure.
University of Texas Medical Branch.Disorders of the hypothalamus and pituitary gland.
