Neuro - FA p478-498 Flashcards
what induces the overlying ectoderm to differentiate into neuroectoderm and neural plate
notochord
notochord becomes what in adults
nucleus pulposus
list the 3 major region that makes up the three primary vesicles of developing the brain
fore, mid and hind brain
what do the proescephalon form
telencephalon & diencephalon
what does the telencephalon form
cerebral hemisphere, basal ggl and lateral ventricle
what does the diencephalon form
thalamus, hypothalamus and 3rd ventricle
what does the mesencephalon form
midbrain and aqueduct
what does the rhombocephalon divide into
metencephalon and mylencephalon
metencephalon forms
pons, cerebellum and upper part of 4th ventricle
myelencephalon forms
medulla and lower part of 4th ventricle
where do the microglia cells originate from
mesoderm
failure of the bony spinal canal to close with the dura intact is associated with what pathology
spinal bifida occulta (tuft of hair)
spinal problem with normal AFP
spinal bifida occulta
diff btw meningocele and meningomylocele
meningocele: meninges herniate only thru spinal canal meninogemylocele: meninges and spinal card herniation
anencephaly is due to which embryo error?
Failure of rostral neuropore to close –> no forebrain, open calvarium.
failure of left and right hemisphere to separate; which gene and diseases is it associated with? What does MRI show?
holoprosencephaly, sonic hedgehog gene & patau syndrome/fetal alcohol syndrome
MRI - monoventricle and fusion of basal ggl
Cyclopia seen with?
most severe form of holoprosencephaly; trisomy 13, fetal alchohol syndrome
lack of cerebral vermis and an cystic enlarged 4th ventricle? list 2 associations
Dandy walker
associated with non commmunicating hydrocephalus & spinal bifida
what disease is associated with meningomylocele; how does it present?
Arnold Chiari type II - Sx/ paralysis / sensory loss at or below level of lesion
Bilateral loss of pain and temperature sensation in upper limb?
Sphingomyelia
Which part of the spinal cord affected in Sphingomyelia?
Most common at C8–>T1
Intention tremor plus loss of pain and temp sensation in UL?
Chiari I malfomation - cerebellar tonisillar ectopia >3-5mm
assoc w/ syringomyelia
Which fibers are destroyed in Syringomyelia?
crossed fibers in ant white commissure ( spinothalamic tract)
Which arches are responsible for the ant 2/3 tongue? Gen sens’n nerve? Nerve for taste?
1st and 2nd arch, Mandibular n (V3), Facial n (VII)
Which arches for the post 1/3 of tongue? N for gen sens’n and taste?
3rd and 4th arch, CN IX, root is CN X
Function of hyoglossus, genioglossus, and styloglossus?
Hyo - retracts and lower tongue Genio - protrudes tongue Stylo - pulls sides of tongue upwards
Which nerves innervates which muscles of tongue?
All muscles of tongue inn by CN XII, except palatoglossus, by CN X
Nissl staining stains what (what parts of neuron) and what molecular structure?
rER, so therefore only stains the body of neuron, not axon
What is Wallerian degeneration?
disintegration of the axon and myelin sheath distal to site of axonal injury with macrophages removing debris.
Where can axons regenerate?
Peripheral Nervous System
Which neuro cell type is a buffer for EC K+ and removes excess neurotransmitter?
Astrocytes
Marker of Astrocytes? embryo origin?
GFAP; from neuroectoderm
Embryo origin of microglial cells?
mesodermal origin, from monocytes in Bone marrow
In HIV, what neurological reaction occurs in the CNS and with which cell type?
fomation of multinucleated giant cells from microglia
Which cells produce the myelin sheath in CNS and PNS?
CNS - oligodendrocytes PNS - Schwann cells
What type of channels are seen at the nodes of Ranvier?
Na+ channels (where AP happens!)
Schwann cells are injured in which disease, causing ascending paralysis? Assoc with which microbe?
Guillan Barre syndrome, C. jejuni
Embryo origin of Schwann cells?
neural crest
What is the difference in myelination between Schwann cells and oligodendrocytes? (other than location)
A Schwann cell can only myelinate one single PNS axon An oligodendrocyte can myelinate several (about 30) CNS axons
What neuro cell have a fried egg appearance histo wise?
Oligodendroglia
What 3 diseases are associated with damage to oligodendroglia?
MS, PML (Progressive multifocal leukoencephalopathy), leukodystrophy
Difference between C and A delta fibers?
C - slow and unmyelinated (C student is slow) A - fast, myelinated)
Where are meissner corpuscles located? What do they sense?
hairless skin, fine touch and position sense
Where are pacinian corpuscles located? What do they sense?
Deep skin layers, ligaments, joints vibration, pressure
Where are Merkel discs located? What do they sense?
Finger tips, superficial skin Pressure, deep touch, position sense
Where are ruffini corpuscles? What do they sense?
finger tips, joints Pressure, slippage of objects along surface of skin, joint angle change
Location of synthesis of Ach? Inc /Dec in which disease?
Made at Basal nucleus - Inc in Parkinsons, Dec in Alzheimer, Huntingtons
Synthesis location of Dopamine
Ventral tegmentum, Substancia Nigra (pars compacta)
Inc/Dec Dopamine in which diseases?
Dec in depression, parkinson, Inc in Schizophrenia, Huntington Dopamine involved in initiation of movement, so dec in depression (dec will to do activity) and parkinson (issue starting movement)
GABA is made in
Nucleus Accumbens (GABANA)
GABA dec in
Huntingtons, Anxiety ( dec inhibition of movement)
Where is NE made?
Locus ceruleus
NE inc/Dec in?
Inc = anxiety, dec = depression
Serotonin is made where?
Raphe nucleus
Serotonin is inc/dec where?
Dec in Anxiety, Depression and Parkinson’s
Embryo origin of dura mater vs arachnoid/pia mater?
Dura - mesoderm Arachnoid/pia - neural crest
3 parts to the BBB?
Tight junctions between nonfenestrated capillary endothelial cells, BM, Astrocyte foot processes
What substances can penetrate the blood brain barrier?
Glucose and amino acids cross slowly by carriermediated transport mechanisms. Nonpolar/lipid-soluble substances cross rapidly via diffusion.
Where is there a break in BBB to allow for secretion?
At the Hypothalamus for the secretion of ADH, Oxytocin and releasing factors.
2 major inputs to HT not protected by BBB?
- OVLT (organum vasculosum of lamina terminalis, senses changes in Osmo 2. Area postrema
Which area of HT manages hunger? Stimulated/inhibited by?
Lateral area - Inc by Ghrelin, inhibited by leptin
A cranipharyngioma of this area of the HT leads to hyperphagia, stimulated by what hormone?
VM - can be stimulated by leptin
Which autonomic nervous system affects the cooling center?
PANS - bc when you’re resting and digesting, you want to be cool.
Which nucleus causing cooling?
Ant - for A/C
Which nucleus is responsible for heating?
Post - her butt is HOT
Which nucleus is responsible for circadian rhythm?
Suprachiasmatic nucleus - You need to see light to have a good circadian rhythm
Ipsilateral proprioceptive information from spinal cord travel to cerebellum through ____ ?
inferior cerebellar peduncle
Input from contralateral cortex to cerebellum through ____ ?
middle cerebellar peduncle
output: Cerebellum to contralat cortex through ____ ? from what cell type, and is it stimulatory or inhibitory
Superior Cerebellar peduncle; from purkinje cells, inhibitory
patient has damage to lateral lobes of cerebellum. what are the symptoms?
fall towards injured sides affects voluntary movement extremities
Patient with truncal ataxia. which part of cerebellum, which other symptoms?
Medial lesions (vermis, fastigial nuclei, or flocculonodular lobe) - truncal ataxia w/ nystagmus, head tilting, bilateral motor defecits
Liste the Deep nuclei in cerebellum
Don’t Eat Greasy Food Dentate, Emboliform, Globose, Fastigal
circardian rhythm which nucleus
suprachiasmatic nucleus
describe the pathway of melatonin release
SupraChiasmaticNucleus –> NE –> pineal gland –> Melatonin
Extraocular movements during REM sleep is due to activity of what?
PPRF paramedian pontine reticular formation/conjugate gaze center
List the causes that decrease REM/ delta wave sleep
alcohol, benzo, barbituates - dec both. NE - dec REM sleep
How does Depression affect REM sleep?
Depression increases total REM sleep but decreases REM latency, dec N3, repeated nighttime awakenings, early morning awakening (terminal insomnia).
when stage of sleep does bedwetting occur? and what other 2 patho occurs in that stage too?
Stage N3 (Delta) others: sleep walking, night terrors
what are the difference between nightmares and night terrors?
nightmares in REM sleep
night terrors in Stage N3
treatment of night terrors and sleepwalking
BDZ - they lower stage 3 and REM sleep.
treatment of sleep enuresis
oral desmopressin ADH analog (nasal form is banned) Imipramine, Amitriptyline Nortriptyline (TCAs) not preferred bc of Side effects (alpha (-)’r so postural HTN, and anti-muscarinic). Tx of choice - motivational therapy
Bruxism, which stage
“You grind your teeth like spindles and complexes in most amount of time” - Sleep spindles and K complexes. -which is stage N2 (45% = most amount of time)
What happen in REM -eyes -motor -brain O2 -pulse and BP
-eyes: REM -motor: loss -brain O2: increased -pulse and BP: increased and variable - sex arousal -dream “BRAIN ON BODY OFF”
What EEG waveforms are seen in sleep stages, in order?
at night, BATS Drink Blood
Beta
Alpha
Theta
Sleep spindles and K complexes
Delta
Beta
Where do you see Beta?
eyes open (awake) and REM
Characteristics of Beta wave
High frequency, low amplitude
Which wave has low frequency and high amplitude
Delta wave slow and big
Thalamus relay for all ascending sensory information except
olfactory
VPL input/output, what does it sense?
from Spinothalamic and Dorsal Column to Primary somatosensory cortex Vibration, Pain, Pressure, Proprioception, Light touch, temperature
where does trigeminal and gustatory pathway go?
VPM
LGN is for?
vision (L=light)
MGN (Medial Geniculate nucleus) is for? pathway?
hearing (M = music) Superior olive + inferior colliculus of tectum –> MGN –> auditory cortex of temporal lobe
Motor info to which part of thalamus - which input?
Ventral Lateral nucleus
What part of thalamus is affected in W-Korsakoff?
Ant + Dorsomedial thalamus ( project to mamillary bodies)
what’s the famous 5 F’s of limbic system
Feeding, fighting, fleeing, feeling, Sex
Parts of Limbic system?
Truef hippocampus (red arrows in A), amygdalae, mammillary bodies, anterior thalamic nuclei, cingulate gyrus (yellow arrows in A), entorhinal cortex.
location of the primary motor is precentral or postcentral?
precentral
What is postcentral?
primary somato sensory
cerebral perfusion is primarily driven by
pCO2
what area of the brain is responsible for disinhibition and deficit in concentration, orientation, judgement and may have reemergence of primitive reflex?
frontal lobe
Where is Broca’s area?
inf. frontal gyrus of frontal lobe
where is wernicke area?
Superior temporal gyrus of the temporal lobe
what is the equation for CPP?
MAP - ICP
If CPP is zero, what does that mean?
no cerebral perfusion –> brain death
so in response to inc ICP, what does the body do?
inc MAP to maintain CPP
in what response/reflex do you see acute inc in ICP?
Cushing (hypertension, bradycardia, irregular breathing)
What 2 Spinal tracts are ascending and sense pressure?
Dorsal column - pressure, vibration, fine touch,proprioception
ant Spinothalamic tract - crude touch, pressure
which tract has a 2nd synapse on NMJ?
Lateral corticospinal tract
Which 2 tracts decussate at the 2ND-ORDER NEURON?
Dorsal column Spinothalamic tract (Anterolateral)
Which 2 tracts decussate in medulla?
Dorsal column Lateral corticospinal tract (pyramidal decussation)
Which 2 tracts sense pressure?
Spinothalamic tract Dorsal column
Which 2 tracts cell body in dorsal root ganglion?
Spinothalamic tract Dorsal column
Which tract decussates at anterior white commissure?
Spinothalamic tract
Where is the cell body of Lateral corticospinal tract?
cell body in 1° motor cortex
Which 2 tracts have a 3RD-ORDER NEURON end in Sensory cortex?
Spinothalamic tract Dorsal column
Which tract sends vibration, fine touch, and proprioception to the cortex?
Dorsal column
Where does the Lateral corticospinal tract become LMN?
at spinal cord as 2ND-ORDER NEURON
Which tract sends Lateral: pain, temperature Anterior: crude touch,
Spinothalamic tract
Which artery supplies ASA below ∼ T8?
Adamkiewicz
nerve at the belly button
T10
nerve at nipple
T4
nerve — is IL (Inguinal Ligament).
L1
Nerves innervating the penis
S2,3,4
Diaphragm and gallbladder pain referred to the right shoulder via — nerve
phrenic
Gland for melatonin secretion, circadian rhythms?
Pineal gland (neroectoderm)
CN nuclei that lie medially at brain stem:
III, IV, VI, XII. “Factors of 12, except 1 and 2.”
Area for conjugate vertical gaze center?
Superior colliculi
Area of midbrain for auditory?
Inferior Colliculi
Midbrain contains which nuclei?
CN III, IV
Pons contains nuclei of which CN?
CN V, VI, VII, VIII
Medulla contains nuclei of which CN?
CN IX, X, XII
Spinal cord contains nucleus of which CN?
CN XI
CN nuclei position: Lateral nuclei = Medial nuclei =
Lateral nuclei = sensory (aLar plate). —Sulcus limitans— Medial nuclei = Motor (basal plate).
Pathway of Miosis
1st neuron: Edinger-Westphal nucleus to ciliary ganglion via CN III 2nd neuron: short ciliary nerves to pupillary sphincter muscles
Pathway of Mydriasis
1st neuron: hypothalamus to ciliospinal center of Budge (C8–T2) 2nd neuron: exit at T1 to superior cervical ganglion (travels along cervical sympathetic chain near lung apex, subclavian vessels) 3rd neuron: plexus along internal carotid, through cavernous sinus; enters orbit as long ciliary nerve to pupillary dilator muscles. Sympathetic fibers also innervate smooth muscle of eyelids (minor retractors) and sweat glands of forehead and face.
(CN V2) goes through what foramen
Foramen Rotundum
CN I goes through what foramen? and what reproductive pathology is associated with CN 1
cribriform plate kallman syndrome
CN III, IV, V1, VI, goes thru
Superior Orbital Fissure
central retina vein goes thru which foramen? with what?
optic canal & ophthalmic artery
middle meningeal artery goes through
Foramen spinosum
what cranial nerve is been tested when you look down from already adducted eye
Superior Oblique (CN 4) trochlear
what nerve innervates the parotid gland
CN 9
head turning what nerve is responsible
Spinal Accessory
Visceral Sensory information (e.g., taste, baroreceptors, gut distention). is seen in what vagal nuclei
Nucleus Solitarius
Motor innervation of pharynx, larynx, upper esophagus (e.g., swallowing, palate elevation) is seen in what nuclei
Nucleus aMbiguus
tongue movement is innervated by what nerve
hypoglosseal
Sends autonomic (parasympathetic) fibers to heart, lungs, upper GI. is by what vagal nuclei
dorsal motor nucleus
list three muscles to close the jaw
Masseter, Temporalis and Medial ptyerigoid
what muscles open the jaw
Lateral Ptyerigoid
what cranial nerve pass through the cavernous sinus
CN 3, 4, V1, V2 & 6
what artery is also found in the cavernous sinus
Internal Carotid Artery
Bonus: what brachial arch does maleus incus and stapes come from
Malleus & Incus (first brachial arch) Stapes (2nd brachial arch)
Snail shaped fluid filled cochlea that contains basilar membranes that vibrates secondary to sound waves refers to the…..
inner ear
low frequency (wide ; flexible) of sound heard at apex in the inner ear is near what area?
Helicotrema
High frequency (thin; rigid) is best heard at —-
base of cochlea
what does CN V3 pass through
foramen ovale
what nerve is responsible for the periauricular touch sensation of the ear
Vagus Nerve post auricular
list 2 GABA receptors that works by Cl- influx
A and B A is in brain B is in retina
What is the function of parasympathetic out of CN 3
pupillary light reflex
What goes through internal capsule in the visual pathway?
Dorsal optic radiation
Where is the uncus?
medial temporal lobe
Inflammatory infiltrate in the endoneurium seen in which disease?
Guillan Barre
Embryo origin of Meninges?
Dura mater - Derived from mesoderm. Arachnoid mater—. Derived from neural crest. Pia mater—Derived from neural crest.
Dural venous thrombosis presents w.?
Signs of inc ICP- headache, focal neuro deficits, seizures.
Aff / Eff path of corneal reflex?
Aff - V1 (ophthamic, nasociliary br) Eff - VII (temporal br, orbicularis oculi)
Aff / Eff path of Lacrimation reflex?
Aff - V1 Eff - VII
Aff / Eff path of Jaw jerk?
Aff - V3 (SS) Eff - V3 (SM - motor )
Aff / Eff path of Pupillary reflex?
Aff - II Eff - III
Aff / Eff path of gag reflex?
Aff - IX Eff - X
Achilles reflex?
S1,S2
Patellar reflex?
L3, L4
Biceps reflex?
C5, C6
Triceps reflex?
C7, C8
Cremaster reflex?
L1, L2
Anal wink reflex?
s3, s4
Moro relfex?
“Hang on for life” reflex—abduct/extend arms when startled, and then draw together
Movement of head toward one side if cheek or mouth is stroked (nipple seeking)
Rooting reflex
Sucking relfex
Sucking response when roof of mouth is touched
Palmar reflex
Curling of fingers if palm is stroked
Dorsiflexion of large toe and fanning of other toes with plantar stimulation is sx of what in an adult?
Sign of an UMN lesion
Galant reflex?
Stroking along one side of the spine while newborn is in ventral suspension (face down) causes lateral flexion of lower body toward stimulated side
Testing for reflexes: Biceps = Triceps = Patella = Achilles =
Biceps = C5,C6 nerve root. Triceps = C6,C7 nerve root. Patella = L3,L4 nerve root. Achilles = S1,S2 nerve root
Level of cremaster reflex?
L1,L2
Level of anal wink reflex?
S3,S4
What is Lissencephaly?
Failure of neuronal migration resulting in a “smooth brain” that lacks sulci and gyri.
Ependymal cells are covered with cilia and microvilli, for what?
. Apical surfaces are covered in cilia (which circulate CSF) and microvilli (which help in CSF absorption)
Reaction of neuronal cell body to axonal injury. Changes reflect Inc protein synthesis in effort to repair the damaged axon - what is this?
Chromatolysis
Characteristics of Chromatolysis?
Round cellular swelling Displacement of the nucleus to the periphery Dispersion of Nissl substance throughout cytoplasm
Vomiting center coordinated by which tract? rec info from?
Solitary tract, info from the chemoreceptor trigger zone (CTZ, located within area postrema in 4th ventricle), GI tract (via vagus nerve), vestibular system, and CNS
5 receptors input into the CTZ - what are they?
: muscarinic (M1), dopamine (D2), histamine (H1), serotonin (5-HT3), and neurokinin (NK-1) receptors.
Drugs that target CTZ?
5-HT3, D2, and NK-1 antagonists used to treat chemotherapy-induced vomiting. H1 and M1 antagonists treat motion sickness; H1 antagonists treat hyperemesis gravidarum.
How is mesocortical pathway affected in schizophrenia?
dec activity = “negative” symptoms (eg, anergia, apathy, lack of spontaneity).
how is mesolimbic pathway affected in schizophrenia ?
inc activity = “positive” symptoms (eg, delusions, hallucinations).
What disease affects the nigrostriatal pathway - how so?
Dec activity = extrapyramidal symptoms (eg, dystonia, akathisia, parkinsonism, tardive dyskinesia). Affected in Parkinson’s
If tuberoinfundibular pathway is affected, then?
dec activity –> inc prolactin –> dec libido, sexual dysfunction, galactorrhea, gynecomastia (in men).
When does hypoxemia increase CPP?
Hypoxemia increases CPP only if pO2 < 50 mm Hg
CPP is directly proportional to Pco2 until Pco2 _______?
CPP is directly proportional to Pco2 until Pco2 > 90 mm Hg.
Infarct in watershed areas lead to what sx?
Infarct due to severe hypotension –> proximal upper and lower extremity weakness (“manin-the-barrel syndrome”), higher order visual dysfunction (if posterior cerebral/middle cerebral cortical border zone stroke).
Presentation of venous sinus thrombosis
—presents with signs/symptoms of inc ICP (eg, headache, seizures, papilledema, focal neurologic deficits). May lead to venous hemorrhage
Which conditions inc the chance of venous thrombosis
hypercoagulable states (eg, pregnancy, OCP use, factor V Leiden).
Solitary tract - fxn and CN?
Visceral Sensory information (eg, taste, baroreceptors, gut distention)
CN VII, IX, X
Nucl ambiguus - fxn and CN?
Motor innervation of pharynx, larynx, upper esophagus (eg, swallowing, palate elevation)
IX, X, XI (cranial portion)
Dorsal motor nucleus - fxn, CN?
Sends autonomic (parasympathetic) fibers to heart, lungs, upper GI CNX
What level of spine is LP done?
b/w L3 and L5
Subarachnoid space extends to what level of spine?
S2 vertebra lower border
