Cranial Flashcards
1
Q
auricle
A
aka pinna
- collects sound
- help in sound localization
- most efficient in directing high frequency sounds to the eardrum
2
Q
external auditory canal
A
- “S” - shaped
- lined with cerumen glands
- outer 1/3 = cartilage; inner 2/3 = mastoid bone
- increases sound pressure at tympanic membrane by 5-6 dB (due to resonance)
3
Q
mastoid process
A
- bone ridge behind the auricle
- provides support to the external ear and posterior wall of the middle ear cavity
4
Q
tympanic membrane
A
- thin membrane
- forms boundary between outer and middle ear
- vibrates in response to sound
- converts acoustical energy –> mechanical energy
5
Q
ossicular chain
A
malleus, incus, stapes
- smallest bones in the body
- act as a lever system
- footplate of stapes enters oval window of cochlea
6
Q
eustachian tube
A
- lined with mucus membrane
- connects middle ear to back of the throat (nasopharynx)
- equalizes air pressure
- normally closed except during yawning or swallowing
- not part of the hearing process
7
Q
stapedius muscle
A
CONCERT
- connects the stapes of the middle ear wall
- contracts in response to loud sounds AKA acoustic reflex
tries to protect hearing from loud sounds
8
Q
cochlea
A
- snail-shaped organ with a series of fluid-filled tunnels
- converts mechanical energy –> electrical energy
9
Q
oval window
A
- located at the footplate of the stapes
- footplate vibrates –> cochlear fluid is set into motion
10
Q
round window
A
- functions as the pressure relief port for the fluid
- set into motion initially by the movement of the stapes in the oval window
11
Q
organ of Corti
A
- the end organ of hearing
- contains stereocilia and hair cells
12
Q
hair cells
A
frequency specific
- high-pitch sounds = base of cochlea
- low-pitch sounds = apex of cochlea
when the basilar membranes moves, a shearing action between the tectorial membrane and the organ of Corti causes hair cells to bend
13
Q
vestibular system
A
- consists of 3 semi-circular canals
- shares fluid with the cochlea
- controls balance
- no part in hearing
14
Q
central auditory system
A
8th cranial nerve AKA auditory nerve = carries signals from cochlea to brain (temporal lobe/auditory cortex)
- fibers of the auditory nerve are present in the hair cells of the inner ear
Auditory cortex = temporal lobe of the brain where sound is perceived and analyzed
15
Q
pathway of how sound travels through the ear
A
acoustic energy (sound waves) channeled in ear via pinna –> strike TM –> vibration of TM –> acoustic converted to mechanical energy –> malleus sets ossicles in motion (amplify sound) –> stapes moves in and our of oval window of cochlea in a fluid motion –> fluid movement –> membranes in organ of corti to shear against hair cells –> mechanical converted to electrical energy –> auditory nerve –> brain for interpretation
16
Q
3 salivary glands
A
- parotid
- submandibular
- sublingual
17
Q
parotid gland
A
- largest of salivary glands
- wrapped around the mandibular ramus
- secretes saliva through Stenson’s duct
- mastification and swallowing
18
Q
innervation of the parotid gland
A
Sympathetic: originates from superior cervical ganglion
- travels along internal carotid artery + branches
Parasympathetic: originates in the inferior salivatory nucleus
- leaves via tympanic nerve synpases in otic ganglion –> form auriclotemporal nerve –> parotid
19
Q
vasculature of the parotid gland
A
- external carotid
- external/internal branches of the jugular veins drain
lymphatics: pre-auricular
20
Q
secretion of the parotid gland
A
First step in digestion = alpha-amylase secretions (starches)
- breaks down amylose and amylopectin (hydrolyze 1,4 bonds)
21
Q
TMJ
A
located in the front of the ear where the skull and lower jaw meet
22
Q
oral cavity
A
- mouth: O’s whatever that means
- lips: vermillion border
- gums: fibrous tissue
- teeth
- hard palate
- soft palate
23
Q
external nose
A
skin: thin to thicker - sebaceous glands
lining: squamous epithelium in vestibule transitions to pseudostratified ciliated columnar respiratory epithelium with seromucous membrane
24
Q
nasal muscles
A
elevators: proceris, levator labii, superioris alaque nasi
depressors: alar nasaris, depressor septi nasi
compressor: transverse consalis
dilator: dilator naris posterior and anterior
25
external nasal blood supply
artery: facial
- sellar and dorsal areas (int. maxillary - infraorbital and opthalmic)
veins: same
lymphatics: superior mucosa (posterior to retropharyngeal and anterior to upper deep cervical and submandibular)
26
internal nasal blood supply
- Kiesselbach plexus: ant 1/3 septum
- sphenopalatine: post inf
- ethmoid: ant and post-superior
- sup labial artery: ant
- greater palatine: post
- veins: direct communication with cavernous sinus- no valves
27
nasal nerve
sensory: trigeminal
v1: opthalmic
v2: maxillary
v3: mandible
parasymp: greater superficial petrosal- branch of facial nerve (7)
28
sinuses
maxillary: 1 each cheek
frontal: 1 each side forehead
ethmoid: 6-12 between eyes
sphenoid: 1 each side behind ethmoid
29
orbital bones
frontal
lacrimal
ethmoid
zygomatic
sphenoid
maxillary
palatine
30
skull
frontal bone
parietal bone
temporal bone
greater wing of sphenoid
31
cranial bones
frontal
parietal (2)
temporal (2)
sphenoid
ethmoid
occipital
32
facial bones
lacrimal (2)
mandible
maxilla (2)
nasal (2)
palatine (2)
vomer
zygomatic (2)
inferior nasal conchae (2)
33
cranial sutures
coronal: parietal and frontal
squamous: parietal and temporal
lamboid: parietal and occipital
occipitomasoid
sagittal: between parietal bones
34
spinal nerves
motor: anterior/ ventral roots
sensory: posterior/ dorsal roots
35
white matter
- myelinated axons, allow for nerve impulses to travel between neurons (gray matter)
- bulk of deep parts of the brain, superficial parts of the spinal cord
36
grey matter
- nerve cell bodies, glial cells (astroglia/ oligodendrocytes), capillaries, and axons/ dendrites
- unmyelinated
- color from capillary blood vessels and neuronal cell bodies
route sensory or motor stimulus to interneurons of the cns
37
Motor
corticospinal tract: voluntary
extra- pyramidal consists of basal ganglia
rubrospinal and reticulospinal tracts provide smoothing of muscle activity
38
UMN
- formed from corticospinal tract fibers
- synapse with LMN in ant horn of spinal cord
- motor root leaves cord anteriorly to join sensory root and become spinal nerve
39
UMN vs LMN
UMN: no atrophy, no fasciculations, spasticity, DTRs increased, contractures, EMG normal
LMN: atrophy, fasciculations, flaccidity, DTRS decreased or absent, no contractures, EMG denervation
40
telencephalon (cerebrum)
- limbic
- cerebral cortex
- basal ganglia
- olfactory bulb
41
limbic system
influences memory formation by integrating emotional states with stored memories of physical sensations
42
Brodmann Functional Area 1,2,3
Primary Somesthetic Area, nuclei from the thalamic neurons
Lesions: decreased touch, pressure, proprioeption --> pain and temp. preserved
43
Brodmann Functional Area 4
UMN motor strip, fine skilled motor activity
Lesions
- Destructive: flaccid paralysis
- Irritant: seizure
44
Brodmann Functional Area 5 & 7
Somatosensory
Lesions: decreased tactile and proprioceptive
- Grapheshesias: can't ID what shape you are holding
- Astereognosis: can't ID what number is drawn on hand
45
Brodmann Functional Area 6 & 8
Premotor Cortex (supplementary motor cortex): fine control of voluntary motor movement
Lesions:
- Contralateral spastic paralysis, apraxia
- Frontal eye fields
46
Calcacrine Cortex
Primary visual area
Lesions:
- Destructive: visual field cuts
- Irritant: visual hallucinations
47
Brodmann Functional Area 18 & 19
Associative visual area
Lesions:
- Visual agnosias (can't recognize objects)
48
Brodmann Functional Area 41
Primary auditory cortex
Lesions:
- Destructive: hearing loss
- Irritants: auditory hallucinations
49
Brodmann Functional Area 40, 42, 44
Cerebral dominance, aphasia, receptive aphasia, expressive aphasia
50
Wernicke (Brodmann Functional Area 22)
grammatically correct, incorrect content (wacky)
51
Broca (Brodmann Functional Area 44 & 45)
expressive/ motor/ nonfluent aphasia: can't speak properly (broken)
52
Diencephalon
Between brain stem and cerebrum
Contains...
1. thalamus
53
diencephalon
Between brain stem and cerebrum
Contains...
1. thalamus
2. epithalamus
3. subthalamus
4. hypothalamus
54
thalamus
Cerebral cortex processing center
Coordination and regulation of afferent signals from cortex (affectual expression)
55
epithalamus
Connection between limbic system and rest of brain
56
subthalamus
Subthalamic nuclei, nerve tracts (motor function control)
57
hypothalamus
ANS (regulation body temp/ endocrine), physical expression of behavior, appestat (feeding center), pleasure center
Anterior: parasympathetic activity (maintenance)
- Basal metabolism, ACH, slows HR, resp, pupillary constriction
Posterior: sympathetic (fight or flight, stress resp)
- T1-L3, noradrenaline increases HR, resp, dilates pupils
58
reticular system
Descending: ANS, extrapyramidal system to voluntary muscles through pontine tegmentum
Ascending: sensory input to thalamus/ cortex (arousal from sleep, wakefulness, attention)
59
medulla
CN VIII-XII: autonomic function, communication between brain and spinal cord
Medulla oblongota: respiration (dorsal/ ventral groups), BP/HR, reflexes, vomiting
60
pons
CN: V,VI, VII: communication between cerebellum and cerebrum (pneumotaxic centre & relay brain messages)
61
cerebellum
Archicerebellum: equilibrium
Paleocerebellum: muscle tone
Neocerebellum: control coordination
62
major coverings of skull and meninges
Dura: epidural space between deep and superficial layers
- Superficial: inner periosteum of skull
- Deep: dura mater proper
- Reflections: separate into two layers
Tentorium: separate cerebellum/brainstem from occipital lobe
Falx cerebri: separate brain hemispheres longitudinally
Arachnoid: subdural space above (enlarges as brain atrophies), subarachnoid space below (location of BV and CSF)
Pia mater: meningeal envelope on brain/spinal cord surface, impermeable to fluid (pierced by BV which nourish brain and spinal cord)
63
C2 and C3
posterior head and neck
64
C4 and T2
adj in upper thorax
65
T4 or T5
nipple
66
T10
umbilicus
67
C5
anterior shoulder
68
C6
thumb
69
C7
index and middle fingers
70
C7/8
little finger
71
T1
inner forearm
72
T2
upper inner arm
73
T2/3
axilla
74
L1
anterior upper inner thigh
75
L2
anterior upper thigh
76
L3
knee
77
L4
medial malleolus
78
L5
dorsum of foot/ toes 1-3
79
S1
toes 4-5, lateral malleolus
80
S3/C1
anus
81
brain vascularization
Carotids: CCA --> ICA (brain) and ECA (dura, bone, scalp, facial muscles)
Veins: no valves, thin, drain into cranial venous sinuses
- Deep: venous sinuses in flax and tentorium reflections
- Superficial: next to arteries
- All leave vein via jugular
82
brachial plexus
Radial: post cord tricep extensors (saturday night palsy)
Sensory: dorsum of hand (not 5th)
Median: anterior interosseous, palmar cutaneous branch, all flexors except FCU and med FDP, pronator teres, pronator quadratus
Ulnar: FCU and med FDP interossei, add policis, opponens digiti minimi, abd digit minimi, flexor digiti minimi brevis
83
lumbar plexus
Lateral femoral cutaneous: L2-L3, sensory nerve
Sciatic nerve: largest peripheral, runs posterior
84
sciatic nerve
Peroneal:
- Articular branches
2 follow superior/inferior lateral genicular arteries to knee
Recurrent branches off common peroneal to the front of the knee via the tibialis anterior
- Lateral sural cutaneous: supplies the skin on the posterior and lateral surfaces of the leg
Posterior tibialis/ tibial: branches into medial and lateral plantar nerves
- Motor: superficial and deep posterior leg muscles
- Sensory: posterior leg and sole of foot
85
olfactory nerve
sensory, brain tract, odors to receptors in nasal mucosa to olfactory bulb to olfactory tract to anterior perforated substance to entorhinal cortex, amygdala, hippocampus, and other parts of limbic system
Testing: eyes closed, nonirritating, familiar smells, compare strength
- Omitted unless trauma or complaint
Symptoms:
- Anosmia: colds, rhinitis, tumors
- Hypersomnia: hysterics, cocaine addicts
- Parosmia (distorted): hallucinations, hysterics, seizures, schizophrenia, uncinate gyrus lesions
- Cacosmia (unpleasant): decomposition of tissue
86
optic nerve
sensory, brain tract, visual acuity/ fields, fundi examination, pupil diameter/ response, accommodation
- Light to retina (rods and cones) to optic nerve to optic chiasm and tract to lateral geniculate nucleus in thalamus to optic radiations to primary visual cortex (calacrine)
- Papilledema, optic atrophy, cytomegalovirus retinitis, CRAO, CRVO, proliferative diabetic retinopathy
87
oculomotor nerve
motor, pupil diameter, pupillary response, accommodation
Eye muscles:
- Superior: levator palpebrae superioris, superior rectus
- Inferior: medial rectus, inferior rectus, inferior oblique
- Parasympathetic: ciliary ganglion
- Injury : pupil dilation and ptosis (upper lid droop) “fixed and dilated”
88
trochlear nerve
motor: superior oblique
89
trigeminal nerve
mixed
Test: palpate masseter while biting down
- Check sharp or dull sensation
Warm cold and vibration if abnormal
- Check next to nose and chin with eyes closed
- Corneal reflex
Ophthalmic
Maxillary
Mandible
90
abducens nerve
motor, lateral rectus (abduction of the eye)
LR6
91
facial nerve
mixed (sensory ⅔ of tongue, motor for facial expressions)
Parasympathetic: salivary and lacrimal glands
Test: asymmetry, puff cheeks, smile, close eyes and attempt to open
Injury: facial droop (bells palsy), dry eyes, dry mouth
Peripheral: whole side paralyzed
Central: forehead spared
92
auditory nerve
sensory (whisper test, Weber, Rhinne)
93
glossopharyngeal nerve
mixed (sensory posterior ⅓ tongue, auditory tube, pharynx, parasympathetic to parotid)
- voice, gag reflex, uvula deviation
94
vagus nerve
mixed (sensory and motor to larynx and pharynx) parasympathetic to chest and abdomen
- Voice, gag reflex, uvula deviation
- Palatoglossus tongue muscle
95
accessory nerve
motor: larynx/pharynx muscles, trapezius, SCM
- check for trapezius asymmetry (shrug shoulders, push head laterally against hand)
96
hypoglossal nerve
motor: 2/4 tongue extrinsic muscles (genioglossus, styloglossus, hyoglossus)
- check for tongue deviation, atrophy, fasciculations
