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1

cells that line the ventricles & central canal of spinal cord, are ciliated and direct flow of CSF

ependymal cells
derived from neuroectoderm

2

embryonic derivation of peripheral nervous system structures: DRG, cranial nerves, melanocytes, chromaffin cells (adrenal medulla), C cells of thyroid, odontoblasts, pia & arachnoid

neural crest
Not CNS but PNS

3

midline sulcus of the pons contains what?

basilar artery

4

cranial nerves that exit the midbrain

CN III and IV

5

connects the two hemispheres of the brain

corpus callosum

6

comprise the striatum

caudate nucleus & putamen
bridge that connects them is the nucleus accumbens

7

responsible for the emotional significance of experiences

amygdala
Note: seizures involving the amygdala cause powerful emotions of fear and panic

8

surrounds the third ventricle

thalamus

9

connects the third and fourth ventricles

cerebral aqueduct

10

channel between the lateral ventricles and third ventricle

foramen of Munro (interventricular foramen)

11

produces CSF

choroid plexus

12

spatial awareness of surroundings, taste, somatosensation

parietal lobe

13

hearing, language comprehension (Wernicke's area), object and face recognition

temporal lobe

14

vision, visual spacial awareness, color perception

occipital lobe

15

movement (primary motor), speech (Broca's area), motor association cortex

frontal lobe

16

dominant hemisphere -> speech comprehension and production

left hemisphere

17

bilateral damage to the amygdala producing the inability to perceive situations as dangerous
other features:
-visual agnosia
-place objects in mouth
-increased sexual behavior
-decreased facial expressions

Kluver-Bucy syndrome

18

long-term memory

hippocampus

19

caudate nucleus, putamen, and globus pallidus

basal ganglia
function: initiation and maintenance of actions
damage to basal ganglia results in movement disorders

20

suspicious for neural tube defects

elevated AFP in amniotic fluid and maternal serum
elevated AChE in amniotic fluid

21

failure of bony spinal canal to close
intact dura
tuft of hair or dimple

spina bifida occulta

22

meninges herniate through spinal canal defect
AFP normal

meningocele

23

meninges and spinal cord herniate through spinal canal defect

meningomyelocele

24

no forebrain
open calvarium -> looks "frog-like"
elevated AFP
polyhydramnios

anencephaly
associated with maternal type 1 DM

25

herniation of cerebellar tonsils through foramen magnum
aqueductal stenosis
paralysis below defect

Arnold-Chiari malformation (Chiari II)

26

parts of cerebellar vermis develop abnormally
hydrocephalus & macrocephaly within first year
delayed: crawling, walking, coordinated movements
cystic enlargement of 4th ventricle

Dandy-Walker

27

-cystic cavity within spinal cord
-capelike bilateral loss of pain and temperature sensation in the upper extremities
-preservation of fine touch
-most common at C8-T1

syringomyelia
Associated with Chiari I malformation (headaches & cerebellar symptoms in presentation but usually asymptomatic in childhood)

28

syrinx in the central canal

hydromyelia

29

motor innervation of the tongue

CN XII

30

taste and sensation innervation of the tongue

Taste: CN VII (ant), CN IX (post)
Sensation: V3 (ant), CN IX (post)

31

degeneration of axon distal to injury and axonal retraction proximally

Wallerian degeneration

32

Group of infections transmitted from the mother to the fetus with similar clinical manifestations.
Involves skin, heart, eye, CNS & causes chorioretinitis

TORCH complex:
Toxoplasma
Rubella
CMV
Herpes

33

GFAP

astrocyte marker

34

phagocytes of CNS that are scavenger cells; when activated these become antigen-presenting cells and produce cytokines

microglia

35

physical support cells of CNS
-repair
-potassium metabolism
-remove excess NT
-component of BBB
-glycogen fuel reserve
-perform reactive gliosis in response to injury (scar tissue)

astrocytes

36

produce myelin in the CNS; can myelinate several axons

oligodendrocytes

37

produce myelin in the PNS; myelinates a single axon

Schwann cells

38

Where are there high concentrations of sodium channels?

nodes of Ranvier

39

derived from neuroectoderm

1. astrocytes
2. oligodendrocytes

40

derived from mesoderm

microglia

41

derived from neural crest

schwann cells

42

injured in multiple sclerosis, PML, & leukodystrophies

oligodendocytes

43

destroyed in Guillain-Barre

schwann cells

44

myelinated fibers that sense Pressure & Vibration
-deep skin layers
-ligaments
-joints

Pacinian corpuscles
Pacinian = Pressure

45

myelinated fibers in hairless skin
dynamic, fine/light touch
position sense

Meissner corpuscles

46

myelinated fibers in basal epidermal layer & hair follicles
Senses pressure, deep static touch, position sense

Merkel discs

47

direct outgrowth of the hypothalamus

posterior pituitary

48

regulates:
-sleep-wake cycles
-thermoregulation
-fluid intake
-growth
-metabolic energy expenditure
-reproduction

hypothalamus

49

hypothalamic nucleus that controls circadian rhythms via connections with the pineal gland

suprachiasmatic nucleus
"you need to sleep to be charismatic"

50

thirst centers nucleus

supraoptic nucleus

51

divisions of the Peripheral Nervous System

1. somatic nervous system
2. autonomic nervous system

52

hemisection of spinal cord resulting in ipsilateral loss of sensation and voluntary muscle movement at level of the injury (stab or gunshot); ipsilateral spastic paresis below level of lesion; ipsilateral loss of light touch, vibration & proprioception below level of lesion; contralateral loss of pain & temperature below level of the lesion

Brown-Sequard syndrome

53

Mean Arterial Pressure - ICP

Cerebral Perfusion Pressure

54

metabolic mechanisms regulate arteriole size to maintain constant cerebral blood flow over a pressure range of 60-150 mm Hg

autoregulation

55

cause increased cerebral blood flow

hypoxia
hypercarbia

56

decreases cerebral blood flow

hypocarbia
causes cerebral vasoconstriction

57

How does too much oxygen produce deleterious effects on brain cells?

formation of free radicals
oxidation of NTs

58

major cerebral branches of the internal carotid arteries

MCA & ACA
These supply 80% of blood to the brain.
MCA receives 80% of carotid blood flow

59

Which arteries supply the spinal cord? From what arteries?

Anterior and Posterior spinal arteries.
Branches of Vertebral arteries which branch from the brachiocephalic (on R) and subclavian (on L)

60

Functional areas of the posterior cerebral arteries

1. Visual cortex
2. hippocampus
3. thalamus
4. hypothalamus

61

most important cause of ischemic stroke

atherosclerosis

62

most common site for hypertensive intracerebral hemorrhage

basal ganglia

63

mechanisms of brain death in ischemia

excitotoxicity, inflammation, programmed cell death
brain hypoxia -> decreased ATP -> Na+ pumps fail -> sodium enters cell -> depolarization -> more sodium influx & water = edema
-extracellular K+ rise causes depolarization ->glutamate release -> activation of NMDA receptor -> calcium influx -> free radical generation & apoptosis pathway activation

64

hyperreflexia
spasticity
positive Babinski

upper motor neuron damage
Note: + Babinski is normal in children up to age 2 yr

65

Which cranial nerve? shrug shoulders or turn face to each side against resistance

CN XI

66

ATPases which are motor molecules for anterograde transport

kinesin and kinesin-related proteins

67

positive membrane potential

depolarization

68

membrane potential that is more negative

hyperpolarization

69

What produces neuronal resting membrane potential?

continual efflux of K+
The membrane is only permeable to potassium under normal resting conditions. It becomes transiently permeable to sodium during rising phase and overshoot phase of action potential.

70

What causes papilledema?

increased ICP

71

What prevents backward propagation of the action potential?

inactivation of sodium channels = refractory period

72

-two or more deficits separated in neuroanatomical space and time
-autoimmune inflammation & demyelination of brain & spinal cord while sparing PNS
-white matter lesions
-oligoclonal bands in CSF**
-MRI is gold standard
-Marcus Gunn pupils
-nystagmus

Multiple sclerosis
Presentation:
-female: age 20-30
-vision loss
-internuclear ophthalmoplegia
-hemiparesis
-bladder/bowel incontinence
-relapsing/remitting

73

-autoimmune destruction of Schwann cells triggered by Campylobacter jejuni & CMV
-molecular mimicry
-symmetric ascending weakness/paralysis
-majority recover completely after weeks or months

Guillain Barre
Acute Inflammatory demyelinating polyradiculopathy

74

virus that infects and kills oligodendrocytes, causing demyelination
associated with immunocompromised (10% AIDS pts)
Causes progressive multifocal leukoencephalopathy PML)
virus replicates in the epithelial cells of the capillaries

JC virus

75

reward nucleus

nucleus accumbens

76

slow progressive demyelination in CNS ending in death
Persistence of defective measles virus in brain
most prevalent in children who were infected before age 2
lack of M component of measles virus, which is required for extracellular spread -> slow infection -> no anti-M antibodies present
monoclonic jerks, blindness, spasticity

Subacute Sclerosing Panencephalitis (SSPE)

77

California encephalitis virus spread by mosquitos
reservoir: chipmunk or squirrel
seizures in 50%

LaCrosse Virus

78

amyloid plaques in CNS
PrP resistant to degradation -> no DNA or RNA
small cysts in gray matter with absence of inflammatory response
long incubation period
progressive dementia, ataxia, myoclonus & death in 5-12months
Host is cattle

Creutzfeldt-Jakob disease
spongiform encephalopathies
Note: CJD can be transmitted by corneal transplant

79

anterograde amnesia vs retrograde amnesia

anterograde: inability to make new memories after neuro insult
retrograde: inability to retrieve memories prior to neuro insult

80

Forms BBB

1. tight junctions of capillary endothelial cells
2. basement membrane
3. astrocyte foot processes

81

region of the hypothalamus that stimulates appetite

lateral
"I have to go out laterally to find food when I'm hungry"

82

area of the hypothalamus that dissipates heat

anterior
the posterior conserves heat -> "hot posterior!"

83

functions of limbic system: HOME

Homeostatic functions -> autonomic & neuroendocrine
Olfaction
Memory
Emotions and drives

84

nucleus that contains the major cholinergic innervation of the cerebral cortex

nucleus basalis

85

What lobe contains the amygdala?

temporal

86

loss of emotional expression in speech

aprosodia
Emotion is lateralized to the right hemisphere

87

contains medium spiny neurons that modulate the influence of dopamine

nucleus accumbens
Receives projections from the ventral tegmental area (VTA)

88

which hemisphere is involved in attention to both sides of the body?

Right (typically parietal lobe)
lesion to the right hemisphere can result in Left hemineglect.

89

areas not protected by the BBB

OVLT
area postrema

90

motor deficit

apraxis

91

area for planning, control and execution of actions
personality

Frontal Association Cortex

92

term and area for difficulty recognizing and NAMING objects

agnosia -> mismatch of verbal or cognitive symbols with sensory stimuli
temporal association cortex

93

inability to recognize and identify faces

prosopagnosia

94

What is thought to be defective in understanding the intentions of others by a child with autism?

mirror neurons

95

separates the outer ear from the middle ear

tympanic membrane

96

muscles that move the malleus, incus & stapes

tensor tympani (trigeminal nerve)
tensor stapedius (facial nerve)

97

part of the ear involved in balance

vestibular apparatus
Balance receptors are located within the semicircular canals & vestibule

98

auditory receptor organ

organ of Corti
has hair cells with stereocilia

99

main auditory nucleus of the thalamus

medial geniculate nucleus
The inferior colliculus projects to this

100

inability to carry out an action in response to a verbal command

apraxia

101

nonfluent effortful speech
right hemiparesis
comprehends language (simple)

Broca's aphasia

102

fluent speech but nonsense
impaired comprehension

Wernicke's aphasia

103

inability to understand written words

alexia

104

crossed eyes

esotropia

105

wall eyes

exotropia

106

two eyes cannot be aligned

strabismus

107

critical period for language

0-12 years
children can speak a second language with fluent grammar until age 7-8 yr

108

unilateral hearing loss indicates

damage to the ipsilateral nerve or ear
damage to the cortex or thalamus presents as poor speech discrimination, poor sound localization, poor selective attention

109

in newborns: hydrocephalus, mental retardation
on radiograph: periventricular calcifications
Sites of involvement: cortex, basal ganglia, retinae, heart, lungs & liver
mom ingested food contaminated by animal urine or feces

Toxoplasmosis

110

infection of the meninges
fever, headache, nuchal rigidity
CSF: increased lymphocytes, mod increased protein, normal glucose

VIRAL meningitis

111

Degeneration and necrosis of anterior horn cells or spinal cord
fecal-oral transmission
replicates in oropharynx and small intestine
hematogenous spread
Presents with weakness, hypotonia, flaccid paralysis, fasciculations, hyporeflexia, muscle atrophy

poliomyelitis
CSF: increased protein, increased WBCs, normal glucose

112

AD
numerous benign neuromas & optic nerve gliomas
neuromas can develop later into malignant peripheral nerve sheath tumors
mutation of NF1 (encodes neurofibromin -> loss results in active RAS signaling -> expressed in all tissues but especially brain, spinal cord and PNS)
"two hit" hypothesis

neurofibromatosis 1
• Criteria for diagnosis of NF1 (need at least 2)
○ Six or more café au lait spots measuring 5 mm in diameter prepubertal or 15 mm postpubertal
○ Two or more neurofibromas of any type
○ One plexiform neurofibroma
○ Axillary of inguinal freckling
○ Optic glioma
○ 2 or more Lisch nodules
○ Sphenoid dysplasia or thinning of long bone cortex with or without pseudoarthrosis
○ First-degree relative with NF1

113

AD
bilateral benign schwannomas of the acoustic nerve
protein product of mutant allele is merlin

NF2

114

○ Develops at 6 months age
○ Affected children become blind and regress mentally and physically
○ Fatal in early childhood (2-4 years)
○ Motor development plateaus and regresses at 8 months; loss of voluntary movement by age 2
-Causes a deficiency of hexosaminidase A, an enzyme required for catabolism of GM2 ganglioside
AR

Tay-Sachs

Ashkenazi Jewish population

115

degeneration of dorsal columns and roots
impaired sensation & proprioception
progressive sensory ataxia
Charcot joints, shooting pains
Argyll Robertson pupils
Absence of DTRs
+ Romberg

Tabes dorsalis

Tertiary syphilis

116

weakness
atrophy
fasciculations
flaccid paralysis
diminished reflexes and muscle tone

LMN lesion

117

weakness
Babinski
spastic paralysis
clasp knife spasticity
increased reflexes and muscle tone

UMN lesion

118

ascending: pressure, vibration, fine touch, proprioception

Dorsal column
ipsilateral dorsal column -> nucleus cuneatus or gracilis in medulla -> decussates and ascends in the medial lemniscus -> VPL in thalamus to sensory cortex

119

portion of the dorsal column for lower body/legs

Fasciculus gracilis

120

portion of the dorsal column for upper body and arms

Fasciculus cuneatus

121

Lateral: Pain, temperature
Anterior: Crude touch, pressure

Spinothalamic tract
sensory nerve -> ipsilateral gray matter of spinal cord -> decussates anterior white commissure -> contralateral ascends -> VPL thalamus

122

descending: voluntary movement of contralateral limb

lateral corticospinal tract

123

-combined UMN & LMN defects with no sensory, cognitive or oculomotor defects
-defect in SOD1
-fasciculations with atrophy and weakness of hands
-fatal

amyotrophic lateral sclerosis
tx: riluzole

124

level where the spinal cord ends

L1-L2 in the adult

Lumbar puncture is performed between L3-L4 or L4-L5

125

AR
kyphoscoliosis in childhood
GAA repeat -> frataxin -> iron metabolism
muscle weakness & loss of DTRs, vibratory sense, proprioception
Staggering gait
Frequent falls
nystagmus
hammer toes
hypertrophic cardiomyopathy

Friedreich ataxia

○ Onset: typically before adolescence and characterized by incoordination of limb movements, difficulty with speech, diminished or absent tendon reflexes, impairment of position and vibratory senses, cardiomyopathy, scoliosis, foot deformities , type 2 diabetes

126

Ptosis
Anhidrosis
Miosis
associated with lesion of spinal cord above T1: Pancoast tumor, Brown-Sequard, late-stage syringomyelia

Horner syndrome

sympathetic loss of the face

127

levels of nipple and umbilicus
level of the penis

nipple T4 teat pore at T4
umbilicus T10 is at belly butTEN"
penis: S2-S4 "S2, 3, 4 keep the penis off the floor"

128

colliculus corresponding functions
superior?
inferior?

superior colliculus: conjugate vertical gaze
inferior colliculus: auditory
"your eyes are above your ears"

129

corneal reflex
afferent CN? efferent CN?

afferent: V1 (ophthalmic)
efferent: VII (temporal branch)

130

lacrimation
Afferent CN?
Efferent CN?

A: V1
E: VII

131

jaw jerk reflex
Afferent CN?
Efferent CN?

A: V3 sensory
E: V3 motor

132

Pupillary reflex
Afferent CN?
Efferent CN?

A: II
E: III

133

Gag reflex
Afferent?
Efferent?

A: IX
E: X

134

produces aqueous humor

ciliary processes of the posterior chamber

135

gelatinous substance between the back of the lens and retina
Maintains the shape of the eye

vitreous humor

136

Why does increased ICP make the optic disk swell (papilledema)?

the subarachnoid space surrounding the optic nerve is continuous with the subarachnoid space of the brain. Increased ICP will make the optic disk swell.

137

Changes the shape of the lens for focusing

ciliary muscles

138

produced by the ciliary body and flows through the pupil to the anterior chamber to provide nutrients to the cornea & lens

aqueous humor
this drains into the venous blood via the canal of Schlemm. Blockage of the canal of Schlemm leads to glaucoma.

139

crystallin proteins become oxidized and aggregate, usually due to older age

cataract

140

Complication of measles.
Lethal changes in personality, behavior, memory, myoclonic jerks, blindness and spasticity

Subacute sclerosing panencephalitis

141

Location where CN III, CN IV and CN VI enter the orbit of the eye

Superior orbital fissure