The diencephalon, also known as the interbrain or betweenbrain, is one of the major areas of the brain, along with the brainstem, cerebellum, and cerebrum. This structure in the brain contains a number of smaller components of the brain which perform a variety of roles to keep the body functioning. In people with disorders which involve the interbrain, a number of neurological symptoms can manifest and treatment is usually required to address dysregulation of body functions.
This structure houses the thalamus, hypothalamus, pineal gland, and a number of related structures. One of the key roles of the diencephalon is as a relay system for the brain. It accepts sensory input from all over the body, with the exception of olfactory information, and relays this information to relevant areas of the brain so that it can be processed. Whether someone is listening to the sound of an orchestra or picking cherries, the interbrain is involved in the perception of those sensations.
Another role of the diencephalon is in the regulation of the endocrine system. The endocrine system uses hormones to control a variety of bodily functions. Hormone levels fluctuate in response to changing input and the diencephalon is involved in the regulation of hormone levels, from detecting increases and triggering a reduction in production to identifying the need for additional hormones and sending signals to make more. Endocrine disorders are sometimes related to problems with the interbrain; in cases where the overall endocrine system does not appear to be functioning normally structures in the interbrain can be at fault.
More functions of the diencephalon include regulation of the viscera of the body. This occurs on a level which is not conscious, but makes it no less important. This area of the brain is involved in activities like breathing and swallowing, for example. It is also involved in the regulation of the central nervous system and it complements the functions of the limbic system as well.
Disorders of the interbrain can result in a wide variety of symptoms, depending on the area involved, the disorder, and the extent of the problem. Medical imaging studies can sometimes be used to identify problems such as tumors, unusual variations in size, tissue damage, inflammation, or infection. Workups of patients including neurological examinations, testing of hormone levels, and related activities can also provide more information which can help a physician understand the roots of a patient's medical issue.