Anatomy Exam 4

What is a cataract?

-A cataract is clouding of a normally clear lens of the eye. Usually occurs when proteins in the eye start to break down

What suture is found between the various bones of the skull?

-Coronal suture: between frontal and parietal bones -Sagittal suture: between the 2 parietal bones -Squamosal suture: between parietal and temporal bones -Lambdoidal suture: between parietal and occipital bones

Autonomic nervous system

-Involuntary, consists of efferent fibers that stimulate smooth muscles in blood vessels, bronchial tubes, and the digestive tract. Also controls glandular secretions and regulates heart rate. -Two neurons are needed between CNS and effector organ. -Control center is the hypothalamus -Reflex centers for coughing, vomiting, breathing, and pulse rate are in the medulla (brain stem).

extraocular muscles

-levator palpebrae superioris -superior rectus -inferior rectus -medial rectus -lateral rectus -superior oblique -inferior oblique

omohyoid attachment and innervation

2 bellies connected by a muscular tendon. inferior belly arises from the scapula and runs underneath the sternocleidomastoid muscle. posterior belly goes from the clavicle to the hyoid. innervation anterior rami of C1-C3

Spinal nerves - how many? How many cervical, thoracic, lumbar, sacral, coccygeal?

31 total. Cervical (8) Thoracic (12) Lumbar (5) Sacral (5) Coccygeal (1)

What is a hydrocephalus?

A condition in which cerebrospinal fluid builds up within ventricles, blocking cerebral aqueduct. The bones and brain enlarge in a fetus. In a fetus a shunt can be placed to inutero to drain excess fluid and prevent mental retardation. In a adult intracranial pressure increases and causes headaches and brain damage if a shunt is not place to drain fluid

medial rectus muscle action and innervation

Adducts eye Innervated by oculormotor n. (CN III)

Ventricular system

All the ventricles contain a choroid plexus which is a capillary-like structure that produces CSF continuously. CSF functions as a shock absorber, transports nutrients to cells and removes waste products, and maintains the ion balance with the nerve tissue.

Fontanelles. When do they close?

Anterior- 18 to 24 months Posterior- 1 to 2 months Anterolateral- 3 months Posterolateral- 1 to 2 m.

lateral corticospinal tract

Efferent, motor tract (pyramidal tract- originates in the cortex). Originate in the cortex in Brodmann area 4. Passes through the cerebral peduncles and then pyramids of the medulla. It carries fine motor control. -Damage= spastic paralysis: no brain control of muscles if upper motor neuron is damaged. Reflex arc through the spinal cord still works so muscle tone is maintained. Flaccid paralysis: lower motor neuron damage so no nerve impulse reaches the muscle and the muscle will atrophy.

abducens nerve VI

Eye movement

Which branches of the external carotid arteries have palpable pulses

Facial artery and superficial temporal artery

internal acoustic meatus contains

Facial n (CN VII), vestibulocochlear n (CNVIII)

Arteries of the brain

Internal Carotid Anterior Cerebral Artery anterior communicating artery Middle Cerebral Artery Vertebral Artery Basilar Artery Posterior Cerebral Artery posterior communicating artery

Vagus nerve X

Larynx, respiratory, cardiac, and gastrointestinal systems

Auditory ossicles - which one is in contact with the tympanic membrane?

Malleus: connected to the tympanic membrane and moves when sound strikes the membrane Incus: attached to the malleus Stapes: attached to the incus. Fits in the oval window leading to the ear and causes the fluid in the cochlea to move. This stimulates hair cells which sends impulses through the cochlear nerve.

Foramen rotundum contains

Maxillary nerve (CN V2)

Pterion

Most vulnerable area of the skull where the frontal, parietal, temporal, and sphenoid bones join together. It is located on the side of the skull, just behind the temple. Middle meningeal artery located here so epidural hematomas can occur if the pterion is injured

muscles of facial expression and nerve supply

Occipitalis, Galea aponeurotic, frontalis, orbicularis oculi, orbicularis ori, buccinator (CN VII)-facial never to all

spinal accessory nerve XI

Shoulder, arm, and throat movements

Disc herniation. What nerves are affected when a disc between two vertebrae herniates?

Spinal nerves are pinched when a disk herniates. Usually this occurs in the cervical or lumbar spine.(sciatica n.) A herniation cervical spineaffects structures innervated by the cervical and brachial plexus

Branches of the external carotid artery

Superior thyroid Ascending pharyngeal Lingual Facial Occipital Posterior auricular Maxillary Superficial temporal

Types of Dural Venous Sinuses

The straight, superior, and inferior sagittal sinuses are found in the falx cerebri of the dura mater. They converge at the confluence of sinuses (overlying the internal occipital protuberance). The straight sinus is a continuation of the great cerebral vein and the inferior sagittal sinus. From the confluence, the transverse sinus continues bi-laterally and curves into the sigmoid sinus to meet the opening of the internal jugular vein.

Circle of Willis

The vertebral arteries that branch from the subclavian arteries (enter through foramen magnum) and the internal carotid arteries (enter through foramen lacerum) that branch from the common carotid arteries join and form the Circle of Willis

glossopharyngeal nerve IX

Tongue and pharynx, pharynx only

Homunculus

a maplike representation of regions of the body in the brain Sensory (right brain-left side of the body) (left brain-right side of the body)

posterior cervical triangle contents

accessory nerve, branches of cervical plexus, roots and trunks of brachial plexus, phrenic nerve (C3, C4, C5) subclavian artery, transverse cervical artery, supra scapular artery and terminal part of external jugular vein

what vertebral arteries make up the circle of willis

anterior communicating artery, anterior cerebral artery, posterior communicating artery, internal carotid artery, posterior cerebral artery

inferior rectus action and innervation

causes eye to focus downward, depresses it

Anterior cervical triangle contents

common, internal and external carotid. facial, glossopharyngeal, vagus, accessory, and hypoglossal nerves.

levator palpeerde superioris action and innervation

continues into the upper eyelid. opens the eye

Skull foramina

cribriform plate, optic canal, superior orbital fissure, foramen rotundum, foramen ovale, internal acoustic meatus, jugular foramen, hypoglossal canal

lateral spinothalamic tract

crosses over spinal cord. Ascending tract (sensory pathways) that convey sensations of pain and temperature. damage is loss of pain and temperature on the contralateral side of the body

geniohyoid attachment and innervation

deep to the mylohyoid muscle. genoid of mandible to hyoid. innervated by C1 nerve roots wishing the hypoglossal n. (CN XII)

suprahyoid muscles

digastric, stylohyoid, mylohyoid, geniohyoid

superior rectus action and innervation

elevates eye, causes it to focus upward

oculomotor nerve III

eye movement

trochlear nerve IV

eye movement

the posterior 1/3 of the tongue is responsible for what and is innervated by what?

for general sensations and taste, CN IX- glossopharyngeal

Where are arachainoid granulations found primarily? what are they?

found in the superior sagittal sinus. villous extensions of the arachnoid. CSF passes through these granulations and returns venous blood

Superior oblique action and innervation

from posterior orbit hooks around trochlea and inserts superiorly. CN IV- Trochlear

the anterior 2/3 of the tongue is responsible for what and is innervated by what

general sensations- Trigeminal nerve (CN V), Taste- facial nerve (CN VII)

Extrinsic Muscles of the tongue

genioglossus, styloglossus, hyoglossus

jugular foramen contain

glossopharyngeal n (CN IX), Vagus n (CN X), Accessory n (CN XI)

vestibulocochlear nerve VIII

hearing and balance

Hypoglossal canal contains

hypoglossal n (CN XII)

frontal sinus location

in frontal bone superior to the eye

Where is the primary visual cortex?

in the occipital lobe surrounding the calcarine fissure

functions of the limbic system

includes cingulate gyrus, mammillary bodies, parahippocampal gyrus, uncus, amygdala, and hippocampus. Important in regulation of emotions such as pleasure and helps control behavioral changes such as rapid heartbeat related to emotion. It also links intellectual and emotional functions such as feelings and perceptions. The hippocampus is important in the storage and retrieval of memory.

sphenoid sinus location

inferior to sella turcica in the spenoid bone. Posterior to the ethmoid air cells

maxillary sinus location

inferior to the eyes in the maxillary bones (the largest sinuses)

lateral rectus action and innervation

inserts into the sclera Abduction. Abducens Nerve (CN VI)

CSF flow

lateral ventricles->intraventricular foramen of monro->3rd ventricle-> cerebral aqueduct of sylvius-> 4th ventricle( lateral luschka) (medial magendie)->subarachnoid space->arachnoid granulations-> dural Venus sinuses-> Superior vena cava

Dural venous sinuses.

lie between the periosteal and meningeal layers of the dura mater. They are best thought of as collecting pools of blood, which drain the central nervous system, the face, and the scalp. All the dural venous sinuses ultimately drain into the internal jugular vein. Unlike most veins of the body, the dural venous sinuses do not have valves.

frontal lobe function

lies in anterior cranial fossa on frontal bone, Carries out higher mental processes such as thinking, decision making, and planning. Where our personality is formed.

temporal lobe function

lies in middle cranial fossa, important in hearing, olfaction, memory, and learning

what are the different parts of the brain?

limbic system, temporal, parietal, frontal lobes

ethmoid air cells (sinus) location

located in ethmoid bone deep to nasal bones

foramen ovale contains

mandibular nerve (CN V3)

hypoglossal nerve XII

mostly tongue movements

Brodmann area 44, 45

motor speech area; dominate hemisphere only

brodmann area 17, 18

occipital lobe; primary visual cortex. secondary visual cortex associates visual impulses with prior experience

what does the superior orbital fissure contain

ocular motor n. (CN III), Trochlear n. (CN IV), ophthalmic n. (CN V1), abducens n (CN VI)

What does the cribriform plate contain

olfactory nerve (CN I)

dorsal spinocerebellar tract

only sensory tract that does not reach the conscious level responsible for proprioception. damage is ipsilateral loss of proprioception and coordination (ataxia)

the subdivisions of cranial nerve V- Trigeminal nerve

ophthalmic V1, maxillary V2, mandibular V3

what does the optic canal contain

optic nerve (CN II) and ophthalmic artery

from central sulcus to occipital lobe, important in sensation and perception as well as spatial relationships. Integrates info about taste, temperature, and touch

parietal lobe function

Brodmann area 3,1,2

post central gyrus; primary somatosensory cortex, general sensory area from all over the body

brodmann area 41, 42

posterior and inferior to lateral fissure. primary auditory cortex and secondary auditory cortex

Arteries of cerebellum

posterior inferior cerebellar artery anterior inferior cerebellar artery superior cerebellar artery

brodmann area 9,10,11

prefrontal cortex; center for personality and character traits

what is the function and innervation of hyoglossus

pulls tongue downward, CN XII- hypoglossal

what is the function and innervation of genioglossus

pulls tongue out of mouth, CN XII- hypoglossal

what is the function and innervation of styloglossus

pulls tongue posteriorly, CN XII-hypoglossal

Epidural hemorrhage

quick, arterial blood in between dural layers, middle meningeal artery

Brodmann's areas

regions of cortex defined by the relative distribution of cell types across cortical layers (cytoarchitecture)

inferior oblique action and innervation

rotates the eye by having a medial origin and a lateral insertion. CN III- oculomotor n.

olfactory nerve I

sense of smell

Which dural sinus turns into the internal jugular vein

sigmoid sinus

Subdural hemorrhage

slower, venous blood below the dura but above the arachnoid layer, cerebral vein

Infrahyoid muscles include

sternohyoid, omohyoid, sternothyroid, thyrohyoid

sternohyoid attachment and innervation

sternum to hyoid. innervation anterior rami of C1-C3

sternothyroid attachment and innervation

sternum to thyroid cartilage. innervation anterior rami of C1-C3

the stylohyoid attachment and innervation

styloid process of the temporal bone and attaches to the hyoid, facial nerve (CN VII)

the supra hyoid and infrahyoid muscles aid in

talking and swallowing

Muscles of mastication. Nerve supply

temporalis muscle, masseter, lateral pterygoid, medial pterygoid, all innervated by trigeminal n. (CN V2) maxillary division

Paranasal sinuses. Where do they drain?

they drain into the nasal cavity.

thyrohyoid attachment and innervation

thyroid cartilage to the hyoid. innervation anterior rams of C1, carried within the hypoglossal n. (CN XII)

Facial nerve VII

tongue and face

mylohyoid attachment and innervation

triangular shaped muscle derived from the mylohyoid line of mandible to the hyoid. Trigeminal n. (CN V)

digastric attachment and innervation

two bellies that attach to the hyoid bone. anterior belly arises from the digastric fossa of the mandible. Trigeminal n. (CN V) posterior belly arises from the mastoid process of the temporal bone. facial nerve (CN VII)

dorsal column system - function, location, deficits if injured

two tracts fasiciculus gracilis (lower limb and lower trunk) and fasiciculus cuneatus (upper limb and upper trunk) ; sensory information except pain and temperature to the post central gyrus. Damage= absence of light touch, vibration, and propriocepton on the ipsilateral (same side) as damage. cell body in thalamus

subarachnoid hemorrhage

typically due to hypertension or ruptured aneurysm, rupture of cerebral artery

trigeminal nerve V

upper face and eye region, nose and upper teeth, lower face, tongue, and lower teeth. mixed nerve: sensory to face, motor to muscles of mastication

arteries of the brain stem

vertebral artery, anterior spinal artery

optic nerve II

vision

brodmann area 4

yrecentral gyrus; primary motor area-fine motor control