Shock absorption – the CSF encasing the brain absorbs the shock of trauma to the head and spine so that the brain does not collide with the skull. In this way, the exact chemical composition of the fluid can be controlled.Ībout half a litre of CSF is produced every day by the ventricles and flows through these ventricles in a constant stream. Plasma is filtered from the blood to produce CSF. It is produced by the choroid plexus, located in the living of the ventricles. Aside from the CSF, the ventricles are hollow.Ĭerebrospinal fluid (CSF) is constantly bathing the brain and spinal column. The main purpose of the ventricular system is to produce CSF which serves many functions, but mostly to protect the CNS. It wasn’t until 1794 that it was discovered that the ventricles were filled with CSF. This space is therefore occupied by CSF, which is produced by the ventricular system. Pia mater is a delicate inner layer, the arachnoid mater is the middle layer consisting of a web-like structure, and the dura mater is the tough outer layer.ĭespite all this protection, there is still space surrounding the brain which can make it vulnerable to injury. For further protection, the brain is covered in three meningeal layers: pia mater, arachnoid mater, and dura mater. The human brain is fully encased in a skull to protect it from damage. Here the CSF is reabsorbed back into the circulation. It also drains into the subarachnoid cisterns, bathing the brain, between the arachnoid mater and pia mater. It has four openings through which CSF drains into two places of the brain.ĬSF drains into the central spinal canal, bathing the spinal cord. The fourth ventricle is a diamond-shaped structure which lies within the brain stem, at the junction between the pons and the medulla oblongata. The fourth ventricle is the last ventricle of the system which receives CSF from the third ventricle via the cerebral aqueduct. This ventricle also interacts with the fourth ventricle through what is known as the cerebral (or Sylvius) aqueduct, a channel that allows CSF to pass between the third and fourth ventricles. The third ventricle is a very narrow, funnel-shaped structure situated between the right and left thalamus, in the midline between the right and left lateral ventricles, just above the brain stem.Īs well as producing CSF, the third ventricle has direct communication with each lateral ventricle through the Monro foramen. The volume of the lateral ventricles is also seen to increase with age. The lateral ventricles are connected to the following ventricles, the third ventricle, by an opening called the interventricular foramen (or foramen of Monro). The lateral ventricles are C-shaped structures and have three horns which project into three lobes of the brain: the frontal, occipital, and temporal lobes. Each of the lateral ventricles are located in each hemisphere of the cerebral cortex, one in the left hemisphere, one in the right. The first and the second ventricles are known as the lateral ventricles.
Each brain ventricle’s main function is to produce, secrete, and convey CSF. These specific cells are tailored to produce cerebrospinal fluid (CSF) and they secrete the fluid into the ventricles at a relatively constant rate. The ventricles are lined with a specialised membrane called the choroid plexus, which is made up of ependymal cells.Įpendymal cells are glial cells, types of cells which provide physical and metabolic support to neurons. There are four ventricles of the brain: the 2 lateral ventricles, third ventricle, and fourth ventricle. The ventricles are essential for maintaining the central nervous system ( CNS). In this way, the ventricles are linked to each other to function as they should. The brain’s ventricular system is comprised of four ventricles as well as small structures which connect each ventricle called foramina. The ventricles of the brain are cavities which produce and store a substance known as cerebrospinal fluid (CSF). In ancient times, they were thought to house the ‘animal spirit’, a substance which allows the soul to exert control over the physical body. The distinct appearance may be part of the reason why the ventricles were believed to have extraordinary roles. When observing the interior of the brain, the four follow ventricles stand out in contrast to the rest of the brain, which is mostly composed of grey matter. By Olivia Guy-Evans, published March 15, 2022Ĭavities in the brain where protective fluid is made and stored