neuroscience - support structures for the CNS

meninges

a series of protective membranes that minimize damage to brain tissue. It surrounds the brain and extends all the way down the spinal cord

dura mater

made of thick, fibrous material and can get to be 0.8mm thick in the adult body. it is physically attached to the inside of the skull with highly resilient connections found at the sutures between the plates of the cranium

arachnoid mater

the middle layer of the meninges composed of delicate fibers that similar resemble a spider web. within this space, there are protrusions that allow for CSF to drain into sinuses, which allow for recycling of soluble substances. most of the CSF in the brain exists underneath this layer in the space

pia mater

a very fragile layer that is in direct contact with the surface of the brain, and closely follows the sulci and gyri

meningitis

potentially deadly inflammation of the meninges that is commonly caused by exposure to infectious agents like viruses or bacterial such as Neisseria Meningitidis (leaks from the blood into the meninges)

brain circulation

the brain requires oxygen and nutrients to function. this is accomplished by the blood that is pumped around the body using a network of blood vessels called the circulatory system

high demand for oxygen and nutrients

at only 2% of total body weight, the brain receives about 15% of total cardiac input

stroke

extremely common, life-threatening condition that results in a loss of blood flow to the brain

blood-brain barrier

anatomical adaptation that selectively transport substances necessary for normal biological function, while simultaneously excluding potentially harmful invaders from the brain

• physically surrounds the blood vessels in the brain; made up of epithelial cells and a type of glial cells called astrocytes

ventricles

hollow spaces within the brain; a total of four structures and the central canal. they are filled with cerebrospinal fluid, which gives the brain the buoyancy needed to remain “floating” inside the skull

traumatic brain injury

occurs when a movement is too abrupt or sudden that the CSF in the brain is unable to protect the brain from the movement