The Nervous System: Central Nervous System

Vocabulary flashcards covering the Central Nervous System, its anatomy, protective structures, cellular components, and related conditions, based on the provided lecture notes.

Central Nervous System (CNS)

Composed of the brain and spinal cord, essential for homeostasis, containing vast numbers of neurons and synapses, and responsible for perception, actions, feelings, and thoughts.

Glial (Neuroglial) Cells

Non-excitatory cells that make up 75–90% of the CNS, performing various support functions.

Astrocytes

Star-shaped glial cells with numerous functions including communication, neuron development, axon regeneration support, blood-brain barrier formation, synaptic activity modulation, protective functions, electrolyte maintenance, and synthesis.

Microglia

Small glial cells with protective functions, acting as phagocytes to remove bacteria and dead or injured cells, and protecting the CNS from oxidative stress.

Ependymal Cells

Glial cells that line cavities (ventricles) and are involved in the synthesis of Cerebrospinal Fluid (CSF).

Oligodendrocytes

Glial cells responsible for forming myelin in the Central Nervous System.

Schwann Cells

Glial cells that form myelin (primarily in the Peripheral Nervous System, but mentioned in context of myelin formation).

Multiple Sclerosis

An autoimmune neurodegenerative disease characterized by the loss of myelin, where glial cells produce inflammatory agents.

Alzheimer's Disease

A neurodegenerative disease involving the loss of cholinergic neurons and the production of inflammatory chemicals, with glial cells contributing to the inflammation.

Parkinson's Disease

A neurodegenerative disease involving the loss of dopaminergic neurons and the production of inflammatory chemicals, with glial cells contributing to the inflammation.

Cranium

The bones of the skull that provide physical protection for the brain.

Vertebral Column

The column of vertebrae that provides physical protection for the spinal cord.

Meninges

Three protective layers of connective tissue (dura mater, arachnoid mater, pia mater) that surround the brain and spinal cord.

Dura Mater

The outermost and toughest layer of the meninges, meaning 'tough mother'.

Arachnoid Mater

The middle layer of the meninges, characterized by a 'spider-like' appearance.

Pia Mater

The innermost and most delicate layer of the meninges, meaning 'tender mother'.

Cerebrospinal Fluid (CSF)

A clear, watery fluid that bathes the CNS, secreted by the choroid plexus, circulating through ventricles and the subarachnoid space, providing neural buoyancy and maintaining a stable interstitial fluid environment.

Choroid Plexus

A structure composed of pia mater, ependymal cells, and capillaries responsible for secreting Cerebrospinal Fluid (CSF).

Arachnoid Villi

Structures that reabsorb Cerebrospinal Fluid (CSF) into the bloodstream.

Cerebrovascular Accident (CVA) / Stroke

Ischemia (lack of blood flow) to the brain, leading to neurological damage.

Occlusive Stroke

A type of stroke caused by the blockage of blood vessels due to conditions like atherosclerosis and arteriosclerosis.

Transient Ischemic Attack (TIA)

A temporary episode of neurological dysfunction caused by a brief and temporary disruption of blood flow to the brain, often a warning sign of a future stroke.

Hemorrhagic Stroke

A type of stroke caused by bleeding in the brain, often due to an aneurysm or hypertension.

Blood-Brain Barrier

A protective mechanism formed by CNS capillaries (with tight junctions) and astrocytes, regulating the exchange of substances between the blood and the brain's interstitial fluid, allowing selective passage of solutes.

Gray Matter

Composing 40% of the CNS, this region is involved in synaptic transmission and neural integration.

White Matter

Composing 60% of the CNS, this region is responsible for the transmission of information over long distances, characterized by myelination.

Projection Fibers

White matter tracts that connect the cerebral cortex with lower levels of the brain or the spinal cord.

Association Fibers

White matter tracts that connect two areas of the cerebral cortex on the same side of the brain.

Corpus Callosum

A large tract of commissural fibers that connects the same cortical regions on the two sides of the brain, facilitating interhemispheric communication.