Central & Peripheral Nervous Systems 325 L

CNS organization

consists of the brain (including cerebellum, diencephalon, cerebrum, and cerebral hemispheres) and spinal cord

olfactory bulb

optic chiasm

dura mater

composed of two layers (periosteal and meningeal layers)

pia mater

arachnoid mater

2

falx cerebri

falx cerebelli

tentorium cerebelli

subarachnoid space

cerebrospinal fluid

fills the ventricles within the brain

cerebral hemispheres

diencephalon

consists of the thalamus, hypothalamus, and epithalamus

brain stem

consists of midbrain, pons, and medulla

cerebellum

gyri

sulci

central sulcus

precentral gyrus

postcentral gyrus

primary motor area

primary somatosensory area

lateral sulcus

longitudinal fissure

frontal lobe

parietal lobe

temporal lobe

occipital lobe

cerebral cortex

made up of gray matter (unmyelinated axons)

corpus callosum

anterior commissure

septum pellucidum

lateral ventricles

orange part

intraventricular foramen

choroid plexus

makes cerebral spinal fluid (found in diencephalon)

fornix

basal nuclei

little "islands" of gray matter stuck within the white matter of nervous tissue

thalamus

internal medullary lamina of thalamus

cerebral white matter

area filled with myelinated axons

hypothalamus

infundibulum

pituitary gland

epithalamus

third ventricle

mammillary body

pineal gland

midbrain

pons

medulla oblongata

cerebral peduncles

cerebral aqueduct

pyramids

corpora quadrigemina

inferior colliculi

superior colliculi

fourth ventricle

olives

middle cerebellar peduncles

B

vermis

folia

cerebellar nuclei

arbor vitae

anterior lobe of cerebellum

1

posterior lobe of cerebellum

2

olfactory cranial nerve

cranial nerve I

sensory fibers

responsible for smell

optic cranial nerve

cranial nerve II

sensory fibers

responsible for vision

oculomotor cranial nerve

cranial nerve III

mixed fibers (mainly motor)

responsible for eyeball and eyelid movement

trochlear cranial nerve

cranial nerve IV

mixed fibers (mainly motor)

responsible for eyeball movement

trigeminal cranial nerve

cranial nerve V

mixed fibers

responsible for chewing

abducens cranial nerve

cranial nerve VI

mixed fibers (mainly motor)

responsible for eyeball movement

facial cranial nerve

cranial nerve VII

mixed fibers

responsible for facial expression

vestibulocochlear cranial nerve

cranial nerve VIII

sensory fibers

responsible for hearing

glossopharyngeal cranial nerve

cranial nerve IX

mixed fibers

responsible for swallowing

vagus cranial nerve

cranial nerve X

mixed fibers

responsible for efferent output of skeletal muscles of pharynx and larynx and for smooth muscle and lands of thoracic and abdominal organs and for cardiac muscle

accessory cranial nerve

cranial nerve XI

motor fibers

responsible for efferent output of skeletal muscles of pharynx, larynx, neck, and shoulder

hypoglossal cranial nerve

cranial nerve XII

motor fibers

responsible for tongue movement

spinal meninges

consist of pia mater, dura mater, and arachnoid mater

white matter of spinal nerves

spinal nerve

dorsal roots

ventral roots

dorsal root ganglia

central canal

posterior median sulcus

anterior median fissure

gray matter of spinal nerve

consists of the anterior, posterior, and lateral horns

gray commissure

cervical plexus

formed by C1-C4 spinal nerves

innervates the skin and muscles of the neck, shoulder, and arm

brachial plexus

formed by C5-C8 and T1 spinal nerves

supplies sensory and motor nerve fibers to the chest, shoulder, arm, forearm, and hand

major branches include the musculocutaneous, median, ulnar, axillary, and radial nerves

thoracic nerves

formed by T1-T12 spinal nerves

provide both somatic sensory and motor innervation to their corresponding intercostal spaces and some adjacent structures

nerves run their own course after emerging from the cord, innervating a narrow strip of skin in the anterior and posterior portion of the body in line with their emergence point from the spinal cord

lumbar plexus

formed by L1-L4 spinal nerves

innervates lower anterior abdominal wall, groin, thighs, knees, and calves

major branches include femoral and obturator nerves

sacral plexus

formed by L4-S3 spinal nerves

motor control to and receive sensory information from most of the pelvis and leg, along with upper and lower foot

major branch includes the sciatic nerve and inferior/superior gluteal nerves

somatic nerves

nerves that provide voluntary control to skeletal muscle for movement and receive sensory information such as touch, pain, and temperature from the skin

autonomic nerves

nerves that supply involuntary control to internal organs

PNS organization

consists of nerves (cranial, spinal) and ganglia (roots and branches, peripheral nerves, neuromuscular junctions)

association tract

communication of information from one region to another within the same cerebral hemisphere

commissural tract

communication of information from one cerebral hemisphere to the other

projection tract

communication of information between higher and lower brain areas and spinal cord centers