unit 4 lab packet

primary somatomotor cortex

function is to control all voluntary skeletal muscle movement

primary somatosensory cortex

function is to receive all somatic sensory information

Occipital lobe

function is vision

Temporal lobe

function is hearing and olfaction

Insula

function is taste and visceral sensory perception

Olfactory nerve

(CNI)

function is olfaction; passes through cribriform foramina

Olfactory bulb

contains fibers of olfactory nerve (CNI)

Optic nerve

(CN II)

function is vision; passes through optic canal

Optic chiasm

function: some fibers of the optic nerve (CNII) contralaterally cross over here

Infundibulum

function is to connect the hypothalamus to the pituitary gland

Mamillary bodies

it is a part of the limbic system whose function is to

regulate emotions

Cerebral peduncles

function: carry motor information from the cerebral hemispheres to the brain stem and spinal cord

Oculomotor nerve

(CN III)

function is motor to four extrinsic eye muscles and carries parasympathetic innervation to the iris; passes through the superior orbital fissure

Middle cerebellar peduncles

function: connect the pons and the cerebellum

Trigeminal nerve

(CN V)

function: sensory from the face; motor to muscles of mastication; passes through superior orbital fissure, foramen rotundum, foramen ovale

Abducens nerve

(CN VI)

function: motor to lateral rectus eye muscle; passes through superior orbital fissure

Pyramids

function: motor information from the cerebral hemispheres to the brain stem and spinal cord

Decussation of the pyramids

function: motor tracts cross contralaterally

Subarachnoid space

contains cerebrospinal fluid

Arachnoid villi

function: transfer wastes from the subarachnoid space to dural venous sinuses (such as the superior sagittal sinus)

Superior sagittal sinus

contains venous blood

Cingulate gyrus

it is a part of the limbic system whose function is to regulate emotions

Corpus callosum

function: contralateral connection between the right and left cerebral hemispheres

Thalamus

function: all incoming sensory information is relayed to the thalamus first (except for olfaction); filters sensory information going to cortex

Interthalamic adhesion

connects the right and left thalami

Pineal gland

function: secretes a hormone called melatonin which functions in day/night cycle

Superior colliculus

function: visual reflexes

inferior colliculus

function: auditory reflexes

Septum pellucidum

function: separates two lateral ventricles

Interventricular foramen

function: allows CSF to flow from the lateral ventricles into

the third ventricle

Choroid plexus

function: produces cerebrospinal fluid

Conus medullaris

found at L1 or L2

Cauda equina

made up of spinal roots

Filum terminale

formed by the pia mater

Spinal nerve

carries sensory and motor information

Posterior rootlets & posterior root

carry sensory information

Anterior rootlets & anterior root

carry motor information

Posterior ramus

carries sensory and motor information to the skin and muscles of the neck and back

Anterior ramus

carries sensory and motor information to the skin and muscles of abdomen, upper and lower limbs

Posterior root ganglion

contains cell bodies of sensory unipolar neurons

Gray matter

contains cell bodies, dendrites, and interneurons

White matter

contains myelinated axons

Central canal

contains cerebrospinal fluid coming from the fourth ventricle

Phrenic nerve

(C3-C5)

Sensory and Motor innervation: diaphragm

Median nerve

(C5-T1)

Motor innervation: anterior forearm compartment muscles, except for the medial muscles (see ulnar nerve)

Sensory innervation: lateral 2/3 of hand on ventral side; dorsum of fingers 2 & 3

Ulnar nerve

(C8-T1)

Motor innervation: flexor carpi ulnaris; medial half of flexor digitorum profundus

Sensory innervation: medial third of hand; anterior and posterior

Musculocutaneous nerve

(C5-C7)

Motor innervation: anterior compartment of the arm

Sensory innervation: lateral forearm

Axillary nerve

(C5-C6)

Motor innervation: deltoid, teres minor

Sensory innervation: shoulder joint; skin over part of the deltoid

Radial nerve

(C5-T1)

Motor innervation: posterior arm and forearm compartments

Sensory innervation: posterolateral arm and hand, except dorsum of fingers 2 & 3

Femoral nerve

(L2-L4)

Motor innervation: anterior thigh muscles

Sensory innervation: anterior and medial thigh; hip and knee joints; skin of medial leg and foot

Obturator nerve

(L2-L4)

Motor innervation: medial thigh muscles

Sensory innervation: medial thigh; skin over hip and knee joints

Tibial nerve

(L4-S3)

Motor innervation: posterior thigh and posterior leg muscles

Sensory innervation: posterior leg and sole of foot

Common fibular (peroneal) nerve

(L4-S3)

Motor innervation: short head of biceps femoris; lateral and anterior leg muscles

Sensory innervation: skin of anterior and lateral surface of leg; dorsum of foot

Vagus nerve

(CN X)

contains parasympathetic innervation to 80% of the body; sensory for taste from epiglottis and pharynx and general sensation in the oral cavity; motor to larynx

Superior rectus

Function: Pulls eye superior and medial

Innervation: Oculomotor (CN III)

inferior rectus

Function: Pulls eye inferior and medial

Innervation: Oculomotor (CN III)

medial rectus

Function: Adducts eye

Innervation: Oculomotor (CN III)

lateral rectus

Function: Abducts eye

Innervation: Abducens (CN VI)

superior oblique

Function: Pulls eye inferior and lateral

Innervation: Trochlear nerve (CN IV)

inferior oblique

Function: Pulls eye superior and lateral

Innervation: Oculomotor (CN III)

Ciliary body and ciliary muscle

function: changes the shape of the lens to focus objects on the retina

Iris

function: contains muscles that regulate the amount of light reaching the retina by controlling the size of the pupil

sphincter pupillae muscle

function: constricts the pupil to allow less light into the eye; innervated by parasympathetic fibers from oculomotor nerve (CNIII)

Dilator pupillae muscle

function: dilates the pupil to allow more light into

the eye; innervated by sympathetic fibers

Rods

more sensitive to light and permit vision in dim light

cones

responsible for high-acuity color vision

Bipolar cells

receive signals from photoreceptors and send them to ganglion cells

Ganglion cells

receive signals from bipolar cells and send them towards the brain

Optic nerve

(II) formed of axons of ganglion cells

Optic disc

called the blind spot because it lacks photoreceptors

Macula lutea

contains mostly cones

Fovea centralis

contains only cones, providing maximal visual acuity

Anterior segment

contains aqueous humor

posterior segment

contains the vitreous body

Pinna (auricle)

function: funnels sound into the ear; composed of elastic cartilage

Auditory tube (Eustachian tube)

function: connects middle ear to nasopharynx to equilibrate pressure in the middle ear

semicircular canals

function: detect rotational acceleration and deceleration

Vestibule

function: detects changes in head position and linear acceleration and deceleration