Central Nervous System

Ventricles

The 4 connected cerebrospinal fluid filled cavities in the center of the brain.

Cerebral aqueduct

Small narrow tube connecting the third and fourth ventricles.

Choroid plexuses

Network of blood vessels in each ventricle of the brain; produces CSF.

Cerebrum

Most superior portion of the brain responsible for cognitive functions; contains the frontal, parietal, temporal, occipital, and insula lobes.

Cerebral hemispheres

Two symmetrical halves of the cerebrum.

Longitudinal fissure (cerebral fissure)

Separates the two hemispheres of the brain.

Transverse fissure

Separates the cerebrum from the cerebellum.

Sulci

Shallow depression or groove in the cerebral cortex.

Lateral sulcus

Separates the temporal lobe from the frontal and parietal lobe.

Central sulcus

Separates the frontal lobe from the parietal lobe.

Gyrus

Rounded, elevated ridge on the surface of the cerebral cortex.

Precentral gyrus

Part of the brain's frontal lobe that controls voluntary movement.

Postcentral gyrus

Part of the brain that processes general somatic sensations.

Cerebral cortex

Outermost layer of the brain made of gray matter.

Corpus callosum

Thick band of nerve fibers connecting the left and right hemispheres.

Fornix

C-shaped bundle of nerves acting as the major output tract of the hippocampus.

Basal nuclei (ganglia)

Group of nuclei in the brain involved in many functions.

Optic chiasm

Part of the brain where the optic nerves cross.

Diencephalon

Central portion of the brain, superior to the brainstem, inferior to the corpus callosum.

Thalamus

Structure in the diencephalon that relays sensory input.

Interthalamic adhesion

Connects the left and right halves of the thalamus.

Hypothalamus

Regulates hormone production and controls the glands.

Pituitary gland

Makes, stores, and releases hormones.

Infundibulum

Hollow stalk connecting the hypothalamus and pituitary gland.

Epithalamus

Posterior segment of the diencephalon that connects limbic system to the brain.

Pineal gland

Tiny endocrine gland in the middle that helps regulate circadian rhythm.

Corpora quadrigemina

Four colliculi that control visual and auditory reflexes.

Cerebellum

Posterior portion of the brain that regulates motor movement and balance control.

Vermis

Middle part of the brain that connects the two cerebellar hemispheres.

Arbor vitae

Tree-like structure in white matter that provides afferent and efferent info to and from the cerebellum.

Brainstem

Connects the spinal cord to the cerebrum and cerebellum.

Midbrain

Superior part of the brainstem; relays hearing and vision, motor movement, pain, and sleep cycles.

Pons

Links medulla and thalamus, handles unconscious processes and thoughts.

Medulla oblongata

Inferior part of the brainstem; controls vital processes like heartbeat and breathing.

Brain coverings

Three layers of tissue called meninges.

Dura mater

Tough, outermost layer of the meninges.

Arachnoid mater

Thin, web-like layer filled with fluid that cushions the brain.

Pia mater

Thin, clear membrane that adheres to the surface, rich in veins/arteries.

Conus medullaris

Tapered end of spinal cord located near the first two lumbar vertebrae.

Cauda equina

Bundle of nerves at the end of the spinal cord that control movement and sensation in the lower body.

Anterior median fissure

Groove along the anterior midline of spinal cord that incompletely divides it into symmetrical halves.

Posterior median sulcus

Groove in the posterior midline of the spinal cord.

Central canal

CSF filled space that runs through the entire spinal cord.

Spinal gray matter

Tissue in spinal cord made up of neuron cell bodies, dendrites, and axon terminals, located in the center of the spinal cord.

Gray commissure

Thin strip of gray matter that connects the two halves of the spinal cord.

Anterior horn

Part of spinal cord’s gray matter that controls skeletal muscle.

Posterior horn

Part of spinal cord’s gray matter that receives sensory info.

Lateral horn

Small lateral projection that contains neuronal cell bodies of SNS.

Spinal nerve roots

Short branches of spinal nerves that connect the spinal cord to the PNS.

Anterior root

Carries info away from the spinal cord (efferent nerve fibers).

Posterior root

Carries info from the body to the brain (afferent nerve fibers).

Posterior root ganglion

Cluster of neurons in the posterior root of spinal nerve.

Anterior rootlets

Carry motor info out of the spinal cord.

Posterior rootlets

Carry sensory info into the spinal cord.

Spinal white matter

Outer layer of spinal cord containing myelinated axons bundled together.

Funiculus (anterior, lateral, posterior)

Bundle of nerve fibers forming one of the main tracts of the white matter in the spinal cord.