The Functions Of The Diencephalon
The diencephalon of the brain lies above the brain stem and embodies the thalamus, the subthalamus, the hypothalamus, and the epithalamus (including the pineal gland). The overall function of the diencephalon is to coordinate sensorimotoric and unconscious vegetative functions.
The Anatomy of the Diencephalon
As the second subdivision of the forebrain, the diencephalon neighbors the cerebral hemispheres of the telencephalon. Along with the telencephalon, they are the two major divisions of the forebrain (prosencephalon). The third ventricle is also located within the diencephalon, which is one of the four brain cavities or ventricles that are filled with the cerebrospinal fluid.
The diencephalon controls many autonomic functions carried out in the peripheral nervous system and relays information between the various brain regions. It’s also the part that connects the structures of the endocrine system to the nervous system and works together with the limbic system and its structures to generate and manage memories and emotions.
About 80% of the diencephalon is made up of the thalamus. The thalamus appearance is a huge ocular mass of gray matter, and while it appears as a single organ, it’s, in reality, a paired setup. The thalamus is conducted sensory interpretation between the various sensory receptors and the brain, with the exception of sensors related to smell. The intensely specialized areas of the nuclei essentially relay impulses that enter the brain via the exact location in the cerebral cortex.
However, the thalamus is only capable of a limited amount of sensory interpretation, which is not sufficient for an enhanced tactile interpretation. The crude interpretation possible in the thalamus conducts sensory awareness functions including intense pain, and very likely plays a major role in reaction to immediate and intense pain. The thalamus also contributes to the psychological shock that often accompanies phenomenal pain.
The hypothalamus lies just below the thalamus. It’s the furthermost inferior section of the diencephalon that houses a lot of nuclei that are interconnected with different regions of the central nervous system. Although it’s quite small, it’s able to perform a wide variety of functions including the regulation of visceral organs, both directly and indirectly. It’s also responsible for instinctual and emotional reactive processes.
The hypothalamus is often considered an autonomic nervous center. Other vital functions carried out by the organ include the release of different hormones and cardiac regulation. It essentially commands the acceleration or deceleration of the cardiac muscle, as it’s related to physical and emotional stimuli. The pulses don’t go directly into cardiac muscle, but head to the medulla oblongata cardiovascular centers.
It’s also responsible for the regulation of body temperature. The anterior section of the hypothalamus houses highly specialized nuclei that sense changes in the internal body temperature. The tactics aimed at expanding or preserving heat are encouraged by the different impulses that encourage the body to sweat, shiver, and to constrict or expand the cutaneous.
The hypothalamus also serves to regulate the body’s water and electrolyte balance. The body has some specialized receptors within the blood called osmoreceptors. These can detect electrolyte imbalances and any signs of dehydration. When impulses from the hypothalamus are sent out, an antidiuretic hormone is triggered via the pituitary gland.
The sensation of hunger is also triggered by the hypothalamus when blood sugar levels are too low. The sexual sensation center lies within the superior portion of the hypothalamus, and the tactile receptors in genitalia normally respond to the physical sensation of sexual activity. The hypothalamus responds to the proper neural activity and in turn produce orgasms and sexual pleasure.
The posterior section of the diencephalon houses the epithalamus, with a fine roof over the third ventricle. This thin roof is lined with vascular choroid plexus that’s responsible for the production of the cerebrospinal fluid. The pineal gland, whose appearance is similar to a pinecone, projects from the posterior section of the epithalamus. This small tissue mass is thought to perform neuroendocrine functions, though scientific studies are yet to confirm this.
The epithalamus is responsible for the production of melatonin, which has a soothing effect on the central nervous system and it’s typically distributed at night. It’s also involved in the formation of pupillary light reflex. The olfactory system is connected to the epithalamus through stria medullary, and it houses the changeover are for the information from the olfactory system. This information is forwarded from here to the salivatory and motoric nuclei, where for instance, saliva secretion is triggered by the scent of food.
The subthalamus consists of the globus pallidus and the nucleus subthalamic. These two essential components are responsible for the coordination of some specific fine-motor and voluntary motor processes.
This gland is shaped like a little pea and is also known as the cerebral hypophysis. It’s located at the inferior section of the diencephalon and is attached to the hypothalamus. The basic functions of the pituitary gland include the production of hormones and chemicals that are essential for various endocrine functions.