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