Flashcards in Neuro2 Deck (211):
What is a great vein varix?
Compresses pineal body and posterior commissure
Posterior Cerebral artery branches and
THalamogeniculate --> thalamus, choroid plexus, upper midbrain,
Temporal --> inferior temporal complex
Parietooccipital --> visual association
Calcarine --> Primary visual cortex
Posterior pericallosal artery --> anastomose
Brancehs of internal carotid?
anterior chroidal artery
Ischemia in what structure is death? What vein can cause this ischemia
Deep Cerebellum, from the straight sinus or left transverse sinus
MIddle cerebral branches and pathologies
Central - paralysis and paresthesia of head and upper limb
Frontal - broca's
Parietal - body neglect agnosia, apraxia
temporal branch - difficulty localizing sounds
ANgular artery - Wernicke's area.
A space occupying brain bleed can lead to what?
Compression on contralateral PCA. Muscle weakness ipsilateral of brain bleed, called kernohan's notch
If the centromedian nucleus of dorasl thaalmus is lesioned, what is affected?
THe indirect pathway of pain and temperature.
The slow pain information from the trigeminal to the face.
Pt presents with hemianalgesia of the right side of his face, and analgesia of left side of body. Dx?
ALternating anaglesia ( upper medulla lesion of PICA)
Primary descending fibers were destroyed
Spinal lemniscus destroyed
Pt presents with facial anesthesia and paralysis on the right side, the left side has spastic hemiplegia. Dx? Where is this located? What artery could have caused it?
Alternating trigeminal hemiplegia, right sided pons lesion AICA
Pupillary constriction pathway
light --> CN II --> branchium of superior colliculus
A pt presents with involuntary movements of his fingers, absentemindedness and aggresion. What caused this?
degeneration of caudate and putamen.
But also a decreased clearing of glutamate.
Pt presents with hemiballismus, what caused this?
Lesion of subthalamic nucleus. Contralateral
Pt presents with Irregular rapid flowing movements, and a hx of bacterial infection treated with antibiotics.
If the substantia nigra was lesioned, what would the symptoms be?
Tremor. bc this nucleus does pars compacta, pars reticulata, and pars lateralis portions. These are dopaminergic.
A pt has wide based stance and is unable to walk in tandem. What aprt of the cerebellum sucks?
Nodulus, uvula, fastigial nucleus.
because these things do bilateral stuff
Acute onset, sginificant ataxia, intention tremor, no strength weakness. Mx?
Superior cerebellar peduncle contralaterally.
remmeber that this is the efferent fibers place!
Which layers of the cerebral cortex have pyramidal cells?
III. External Pyramidal Cells
V. Ganglionic layer, = internal pyramidal cell layer
A pt may stand with open eyes but fall with closed eyes. Lesion where?
Histological slides show a loss of Purkinje cells. Dx?
What lies next to the inferior colliculus?
The inferior olivary nucleus is at what brainstem level?
Wha tis next to the superior colliculus?
Superior Cerebellar peduncle, trochlear nerve.
Oculomotor nucleus, Red nucleus
Bloody csf means
How many pairs of nerves are there?
What is the thin strand of pia mater that anchors the conus medullaris to the coccyx?
What else is terminating from the ocnus medullaris?
Why does the substantia gelatinosa look so white?
Unmelinated sensory fibers that carry pain and temperature run up these.
Where is Clarke's nucleus?
WHat vetebral level? Fxn?
Lamina VII Nucleus sorta close to the central canal on vertebral levels T1 - L2. Fxn: Sensory processing
Describe the Laminae of the spinal cord, 10 of them. With their function
I. covers substantia gelatinosa - spinothalamic tract
II. Is substantia gelatinosa - pain and temperature info
III - VI: Posterior horn - sensory
VII: Clarke's nucleus - posterior spinocerebellar tracts; T1 -L3 preganglionic sympathetic; S2-S4 preganglionic parasympathetic to pelvic viscera
VIII: Interneuron zones of anterior horn
IX: Motor Neurons in anterior horn
X: Grey matter surrounding Central Canal
Describe special portions of the lamina
T1 - L2 = Clarke's nucleus, Lamina VII, contains posterior spinocerebellar tracts.
T1-L3 = intermediolaeral column; preganglionic sympathetic neurons
S2-S4 = Sacral parasympathetic nucleus; preganglionic parasympathetic neurons to pelvic viscera
Medulla --> C5 = accessory nucleus
C3-C5 = phrenic.
Where is the limbic lobe located?Fxn?
It encircles the corpus calloseum
Emotional responses, drive related behavior and memory
What do arcuate fibers connect?
Arcuate connect same gyri
Longtudinal connect same hemisphere, dif lobes
commissural connect hemisphers
Projection connect body to head.
Where is the primary auditory complex located?
Where is the uncus located?
superior temporal gyrus
Posterior superior temporal gyrus
On limbic lobe
folded into temporal lobe
Amgydala: beneath uncus
What make up the basal nuclei?
What are the deep cerebellum nuclei?
Lenticular nucleus (putamen and globus pallidus; separated by internal capsule)
If a lesion occurs between the spinal cord and the medulla on the right side and takes out both medial lemniscus and spinothalamic tracts, what will the symptoms look like?
What if the lesion occured superior to medulla?
Reduction of touch sensations on the right, and pain and temp sensations on the left.
Everything be contralateral.
What does the anterior cerebral artery supply?
Caudate nucleus, motor and sensory for legs
Risk for thrombosis due to long course.
Pt presents with motor loss, pain and temperature loss, proprioception and fine touch loss on teh left side. What artery hemorrhaged
right lenticulostriate/thalamostriate off the middle cerebral
This supplies: Internal capsule, corpus striatum and thalamus
What are the branches of the MCA and their fxn?
Central artery: Primary motor and somatosensory
Lenticulostriate: Internal capsule, corpus striatum, thalamus
Parietal branches: association cortex
Temporal branches: auditory cortex
Angular a: Wernicke
A pt presents and can hear and comprehend you, but has diffculty responding. Dx and artery?
Broca's Aphasia, Frontal branches of MCA
Expressive Language disorder
Pt presents with body neglect, agnosia (can't interpet senses), apraxia (difficulty motor)
Parietal branches of MCA
Pt presents with difficulty localizing sounds?
A pt presents and is fluent in speech, but does not make any sense.
Wernicke's, angular artery of dominant hemisphere.
A pt presents with facial numbness on the right side, and body numbness on the right side. What artery?
VPL and VPM were hit, so anterior choroidal artery
Thalamus, choroid plexus of lateral ventricle, upper midbrain
Wht artery supplies the primary visual corteX??
What does the anterior spinal artery supply?
What things do PICA And AICA have in common?
Lateral corticospinal tract
hemorrhage of what artery can result in quadriplegia, where the only action you can do is move your eyes verteical?
basilar "Locked in syndrome"
What 3 structures do you need to be able to look left and right? Where are they located?
PPRP Paramedian Pontine
Medial pontine includes what structures:
Lateral Pontine Includes:
Medial Medullary includes:
Medial pontine: Corticospinal, CN VI & VII (gaze palsy and facial droop)
Lateral pontine: Vestibular nuclei - nystagmus; Spinothalamic, spinal nucleus of V, sympathetic tract. VII facial droop
- Lateral Corticospinal, Medial lemniscus, XII
- Lateral corticospinal = contralateral hemiparesis; medial lemniscus = Contralateral proprioception and 2pt touch loss; Hypoglosasl n root = ipsilateral deviation LMN
Lateral Medullary (Wallenburg
- Vestibular, Symapthetic, spinothalamic, V, nuc ambiguus.
- Facial pain and temperature
Contralateral hemianopia with macular sparing is caused by
Posterior Cerebral artery occlusion
or damage to occipiatl lobe
What Sx occurs in an uncal herniation
III compression; occlusion of PCA = contralateral hemiparesis, respiratoy compromise
What type of hydrocephalus do Alzhemiier's pts get?
Supratentorial atrophy of the cortex
What spinal level does the fasciculous gracilis begin?
PCML pathway, GO
ipsilateral nucleus cuneatus/gracilis
Decussates internal arcuate fibers
Rotates in pons - upper extremity are medial now, lower are lateral
Somatosensory cortex in postcentral gyrus
the subdivisions of the somatosensory cortex include 1, 2, 3a and 3b. Describe
1 - deficit in texture discrimination
2 - size and shape
3a - ?
3b - Initial processing of texture, size and shape
What is the secondary somatosensory cortex?
Receives input from ipsilateral SI cortex and VPI thalamus
Lateral Spinothalamic pathway, GO!
- Posterolateral fasciculous - Lissaurer's TRACT!!!!
- Ipsilateral substantia gelatinosa and nucleus proprius
- LSTT (lateral spinothalamic tract)
- LSTT and VSTT meet and become spinal lemniscus
Patient presents with burnt hands, say she put them on the stove and couldn't feel that it was hot. Dx? What other symptoms?
Syringomyelia compressing on the anterior white commissure
Shawl or cape like distribution of pain/temperature loss
BRown-Sequard syndrome presentation?
- Ipsilateral LMN signs
-Ipsilateral UMN signs
- Ipsilateral Proprioception, vibration, light touch, tactile sensation
- Contralteral loss of pain, temperature, and crude touch.
Anterior spinothalamic tract Go
C type enters spinal cord
Fasciculous proprius ipsilaterally
Centromedian nucleus of dorsal thalamus
--> Reticular formation
--> Hypothalamus, limbic system.
- Post Central Gyrus
- Cerebral peduncles
- Anterior pons
- Medullary pyramids
- Decussate at spinomedullary jxn at pyramid
- Lateral corticospinal tract = crossed fibers
- Anterior corticospinal tract = uncrossed
- Hits up that LMN
A patient presents quadriplegic. An MRI shows no hemorrhaging. Mx?
ALS, degeneration of the primary motor cortex or the UMN corticospinal tracts
4 subtypes to cerebral palsy. What are htey and what region do they involve?
Spastic- cerebral cortex
Dyskinetic - basal ganglia
Ataxis - cerebellum
Mixed - multiple areas
What is the mechanism of Polio? Sx?
Polio virus destroys the ventral horn of motor cell bodies
Sx: Asymmetric flaccid paralysis, areflexia, Hypotonia, Atrophy of muscles,
normal sensory exam
Weird extrapyramidal motor tracts:
- Antigravity reflexes
- Reflex inhibition: if a reflex intereferes with a voluntary movement, this inhibits it
- Flexor movement;
- Red nucleus
Tectospoinal: coordinates movement of head with eyes (Colliculus)
Vestibulospinal: extensors against gravity for posture
Fast pain fibers in face patway
come in on the pons
- Spinal trigeminal nucleus, caudal pars (Mandibular posterior, ophthalmic anterior)
- Contralateral trigemincal lemniscus
- Primary somatosensory cortex
Slow pain fiber in face pathway
C fibers enter pons
- Spinal nucleus
- Reticular formation
- BILATERALLY to centromedian nucleus and hypohtalamus
Precise Tactile info from face?
how is V1-V3 arranged
- from oral cavity --> Dorsomedial
- Dorsal trigeminal tract (DCTT)
- VPM on ipsilateral side
- from V1-V3 --> Ventrolateral division
- Trigeminal lemniscus (anerior tract) contralateral side
V1 is anterior,
Proprioceptive info from face?
Unconscious proprioceptive afferents
- Mesencephalic nucleus
- Goes to main sensory and does all the stuff over again.
What are the trigeminocerebellar tracts?
Proprioception from mastication muscles for chewing.
- Goes to mesencephalic
- spinal nucleus
- inferior cerebellar peduncle
- anterior vermis of cerebellum
Texture of food:
- superior cerebellar peduncle
- Anterior vermis of cerebellum
(Tomato vs onion biting)
If there is an upper medulla brainstem lesion,(or PICA stroke) what is the sx and dx?
Sx: Ipsilateral hemianaglesia of face
Contralateral hemianaglesia of body
A pt presnts with right sided trigeminal anesthesia and paralysis; left sided spastic hemiplegia
The right side of the face can feel, but not move.
Alternating trigeminal hemiplegia
Path of pupillary constriction?
CN II -->
Optic tract -->
Brachium of superior colliculus
--> superior collicululs -->
EWN of ipsilateral
Posterior commissure --> EWN Contralaterally
Areas 18 and 19 along with temporal and parietal lobe parts are considered the
Visual association cortex, in the parieto occipito temporal area
If the superior colliculus was taken out, what would the pt sx be?
Retinal reflex = constriction wouldn't be bilateral
Voluntary eye movements left and right
What can cause monoocular blindness?
Contralateral homonymous hemianopia
Contralateral superior quadrantopia
Incongruent contralateral hemianopia with macular sparing
Central a effed
Internal carotid calcification
Vascular lesion of geniculate body
MCA or P. temporal lobe lesion
How do you control your eye movements voluntarily? What pathway?
Frontal eye fields --> corticotectal fibers --> superior colliculus --> LMN III, IV, VI,
Nonvolitional: occipital eye fields
What cauases visual agnosia?
Cannot name or describe an object, but recognizes its use
Left occipital lobe and posterior corpus callosum infarction
What makes up the left half of the visual field?
Right eyes temporal retinal field
Left eyes nasal retinal field
(left of both eyes)
alar plate becomes?
Oligodendrocytes, astrocytes, ependymal cells and CNS neurons are derivatives of what in the nural tube?
What about PNS and Schwann cells?
Neurobalsts in intermediate zone of diencephalon
How is the cerebellum developed?
Alar plate --> Cerebellar swellings --> 4th ventricle --> cerebellum
Cerebral cortex fibers = cerebral peduncles
lateral part of basal plates
The alar plates become what in these 3 structures?
Midbrain = superior/inferior colliculi
Nucleus cuneatus and gracilis
Spinal Cord =
Red nucleus, reticular nuclei, CN III, IV
Medulla = Pyramids
Describe the flexures of the brain and what week they establish brain regions?
Midbrain flexure: midbrain from forebrain
Pontine: metencephalon and myelencephalon
Cervical Flexure: hindbrain from spinal cord.
Describe Cerebral lamina:
II & III. Neurons that project to other cortex areas
IV. Thalamus inputs
V. Projects to subcortical structrues
VI. Thalamus outputs
4&5 form first
What is the sulcus limitans?
Separates the alar and basal plates
Zones of hte spinal cord?
Ventricular = neuroepithlium around spinal cord
Intermediate = grey matter, become neurons
Marginal : white zone = axons
How can you tell type I Arnold-Chiari Malformation from Arnold-Chiari Type 2?
TypeI = ectopia of cerebellar tonsils
Type II: Vermis and tonsils both are herniated
What is Arnold Chiari TYpe 2 associated with?
Hydrocephalus and lumbosacral meningomyelocele?
What causes lissencephaly?
Failure of neuronal migration during week 12
what muscle in the oculomotor nucleus decussates?
What nerves are onthe pons medulla junction
Abducens and facial
The facial nerve uses what ganglion?
What CNs use a corticobulbar tract?
5, 7, 9 10, 11, 12
All the ones with motor fxns that aren't part of the eye
Vestibuloarchi cerebellum path GO
From the vestibular/reticular nuclei
- Through the inferior Cerebellar peduncle
- FLocculonodular lobe
- Fastigial nucleus
- vestibular nuclei and RF
Then you got some LMNs going through vestibulospinal and reticulospinal tracts.
Spinocerebellum path, GO
- Inferior cerebellar peduncle
- cortex of ipsilateral vermis
2 different efferents
- Globose and emboliform nuclei --> superior cerebellar peduncle --> red nucleus and thalamus
- Fastigila nuclei --> Vermis --> vestibualr and reticular nuclei
Pontocerebellum pathway go!
- Pontocerebellar fibers
- middle peduncle, contralateral to lateral cerebellar hemisphere
- Dentate nucleus
- Superior cerebellar peduncle
- COntralateral red nucleus/VLN of thalamus
The inferior cerebellar peduncle contains:
Inferior: Spinal cord and brainstem afferents to cerebellum
Middle: Pontine nuclei to cerebellum
Superior: Only efferents. to diencephalon and brainstem
What's the fxn of the juxtarestiform body?
Juxtarestiform: Bn cerebellum and vestibular structures
Restiform: arise in spinal cord or medulla to cerebellum
How do we keep the other muscles that the oculomotor innervates from moving in a roatation situation?
What about the contralateral abducens?
Vestibular nucleus inhibits the other muscles.
(EBNs excite the omnipause region/EBN to Stimulate ipsilateral abducens
Internuclear ophthalmoplegia = loss of vestibulocular reflexes.
Convergence is still normal.
Friedreich's ataxia is caused by what?
What are Sx?
Lateral coricospinal tract degeneration = spastic paralysis
Spinocerebellar tract = ataxia
dorsal columns = proprioception
DRG= DTR loss
What is the fxn of the caudate?
Caudate: receives cortical inputs from association areas
Globus Pallidus = lenticualr fasciculus, ansa leticularis (disinhibit thalamus)
Putamen = receives input from somatosensory and motor areas
Direct and indirect pathways for the basal ganglia
Just know GPi does all the work and acts on the thalamus.
To turn the thalamus on, you gotta turn the GPi off. Use Gaba from Striatum.
TO turn thalamus off, you gotta turn on the GPi, which means you have to use STN (subthalamic) to stimulate GPi
What basal ganglia fibers are serontonergic?
What are some clinical correlations here?
Serotonin: Raphe nucleus
DOPA: Nigrostriatal fibers = Parkinson's destroys these neurons in the substantia nigra
Huntinton's disease destroys these.
What is the Mx of Parkinson? and Sx?
Mx: Loss of Nigrostriatal fibers which are dopaminergic in the substantia nigra pars compacta
Tremor, Rigidity, Akinesia, Posture, Shuffling
loss of caudate and putamen; low levels of Gaba (striatonigral gone), increase in dopamine. Glutamate cytotoxicity
Sx: Aggression, depression, athetosis, depression, dementia
What is chorea?
- dancing, purposeless movements
What is hemiballism?
Happens from previous rheumatic fever, creates abs against basal ganglia
one flailing limb from contralteral subthalamic nucleus
Athetosis: Sake like movements from basal ganglia
What is the ventral lateral nucleus used for?
Pt presents with hyperorality, hypersexuality, disinhibited behavior
Kluver Bucy syndrome, destruction of amygdalas
What organ regulates the autonmic nervous system?
Pt presents with trouble remembering day to day activities, but still retains all of his old memories. What's effed up?
Hippocampus puts Short term mems into long term mems.
Name the fibers that make up the pathways.
Amygdala --> hypothalamus?
Amygdala --> septal area?
Hippocamus --> septal area?
Cingulate gyrus --> entorhinal fibers?
anterior nucleus of thalamus --> cingulate gyrus
Septal area to hypothalamus?
Ventral amygdalofugal fibers
Medial mammillary nuclei
MFB = dopaminergic
What may cause olfactor hallucinations?
lesion of temporal lobe, hippocampus, amygdala, medial dorsla thalamic nuclei?
A pt presents with a chief complaint of difficulty learning new tasks, understanding written material, and confabulation. Dx? Mx? Cause?
Dx: Korsakoff's syndrome
- mammillary bodies degenerate
can't convert short term to long term
cause: thiamine deficiency commonly seen in alcoholics
What is the fxn of ependymal cells?
Which substance has a higher pH, CSF or Blood?
What are the components of a Blood Brain Barrier?
Endothelial cell layer, Basement membrane, Pericytes, Foot processes of astrocytes and oligodendrocytes
What is the fxn of OVLT? Area postrema?
Subfornical organ? (median eminence of hypothalamus)
OVLT = osmotic sensing
Area postrema - vomiting reflex for toxins
Endorine stuff for PP.
Glut 3 transports what?
Glut 5 transports what?
Glut 3: neurons
GLUT 5: microglia
Where is NKCC located? What helpers does it have?
Apical side, brings in K, Na, Cl. back across her.
Endothelin 1 and 3
What are the rate limiting enzymes for the production of Epinephrine and serotonin?
Tyrosine hydroxylase (tyrosine to dopa)
Tryptophan hydroxylase (tryptophan to serotonin)
For Epi/NE what are the receptors and terminators?
Receptors: alpha beta; terminators: COMT: inactivates epi; MAO - degades NE/serotonin
Receptor: H1, H2
terminator: diamine oxidase
5HT2a - smooth muscle
5HT2c - body weight
5HT3 - vomiting
5HT6 - drug targets
Fxns of dopamine?
Tons of functions:
Substantia nigra: Motor - Parkinsons
Mesolimbic: VTA --> nucleus accumbens - plays role in reward, pleasure addiction
Mesocrtical: VTA --> frontal cortex
Tuberoinfundibular: hypothalamus --> A pit, suppreses prolactin
- Location of synthesis
- Receptor types
- pons midbrain
-septal nuclei, nucleus basalis
- Nicotinic = opens Na channels, NMJ
Muscarininc = M1, M3, M5 = IP3
Fxn: wakefulness for learning and memory
What are the inhibitory proteins?
What are their:
Location of synthesis?
- Gaba = cortex/cerebellum, with glutamtae decarboxylase
-Glycine = spinal cord, strychnines
Termination: Gaba transaminase
GABAa - ionotropic; uses cholrine to inhibit. Also benzodiazepine receptor enhanves inhibition
GABAb - metabotropic, K conductance
Glycine: GlyR? poisoin
GABA & Glycine - inhibit
What are the excitatory proteins?
What are their:
Location of synthesis?
location: presynaptic neuron
alpha ketoglutamate --> glutamate via glutaminase
- AMPA: Fast, voltage dependent; premotor for UMN
- NMDA: slow, but strong EPSP. Must have Glycine and glutamate to kick off Mg, plus PCP blocks this as well!! Long term synaptic changes, learning/memory
NMDAs - excitotoxicity
What are the excitatory proteins?
What are their:
Location of synthesis?
- derived from: POMC
- derived from: Proenkephalins
- derived from: prodynorphins
Receptors of all of them:
Mu: analgesia, respiratory depression. Increases K+ = Hyperpolarizes
Kappa: analgesia, diruesis, sedation, dysphoria. Decrease Ca
Delta: analgesia, decrease Ca
Nociphetin: tolerance to opioids, increases pain.
Fxn: Turn bad feelings into good feelings.
What are the excitatory proteins?
What are their:
Location of synthesis?
Enzymes: made in post synaptic cleft and retrograde actions
CBI --> most abundant GPCR in brain
- decrease adenylyl cyclase activity
CB1 = decrease NT release to protect against excitotoxicity. modulates nociception, protect against cytotoxicity
CB2: Binds 2 AG
Immune - antifinflamatory
viscera - IBD
How does excitoxicity work?
ATP = 0 --> NaK shuts off --> cell depolarizes,--> AP releases EAAs, -->Na gets all used up, --> tons of glutamate in cleft--> increased calcium
Increased Ca activates
1. phospholipase A2
3. Mu calpain
The increased Ca activates what 4 systems, and how do they work?
1. phospholipase A2
- Arachidonate damages membrane by acting as a ryanodine receptor on ER - unfolded protein response
activates Nitric Oxide
3. Mu calpain
Proteolysis via Spectrin and eIF4G
4. Apoptosis of cells
Bcl2 is inhibited
In an ischemic patient, what happens when you give them O2?
Neuron is altered, and when you give them O2 it becomes free radicals.
O2 = ATP = kinases = phosphrylate IF2a = caspace 3
A pt can open their eyes and track things, but they do not responsd to auditory stimuli, pain or hunger. What is this called and what caused it?
Arousal but no awareness
Describe the states of awareness in regards to Arousal and Awareness
Normal: arousal and awareness high
COma: Arousal and awareness low
Vegetative state: Arousal high, Awareness some.
Minimally conscious: high arousal, low awareness, EEG monitored.
Locked in: eerything's there you just can't move.
What are the 5 arousal systems?
1. Excitatory amino acid via RAS and parabrachial nuclei
2. cholinergic (PPT)
3. noradrenergic (Locus Coeruleus
4. Serotonergic (raphe nuclei
5. Dopaminergic (VTA
Origin: Pedunculopntine tegmental
Dorsal and ventral pathway
uses acetylcholine arousal. Baseline
Noradrenergic origin pathway fx
Dorsal and ventral pthas
Same as everything, but this also has quiet awareness and mood
What neurotransmitters are vasoconstrictors?
NPPY Neuropeptide Y
If a pt presents with low respiration, what opioid receptor is being stimulated?
What if teh pt expereinces analgesia and dysphoria? Just analgesia?
Analgesia and dysphoria = Kappa
Analgesia only = delta
What is the action of 2-AG?
Reduces Excitatory AA, which reduces effects of excitotoxicity
What neuotransmitter increases edema?
What is the main inhibitor of the lower central nervous system
What NTs are found in the following:
- Parabrachial nuclei?
- Pediculopontine tegemental nucleus?
- Locus Ceruleus
- Raphe nuclei
- Ventral Tegmental area
Parabrachial & RAS = Excitatory amino acids
Pediculopontine tegemental nucleus: Acetylcholine
Locus ceruleus : Norepinephrine
Raphe nuclei: Serotonin
Tubuloinfundibular: anterior pituitary
Laterodorsal nuclei: ACh
Ischemia is caused by what ion? What receptor is associated with this ion?
What is the effect of Hydrocephalus on Cerebral blood flow? how?
Increase ICP cuts off venous flow, which decreases the cerebral blood flow
What is the path of Dopamine projection in the brain?
Substantia nigra --> VTA --> Nucleus accumbens in the limbic system; and the cortex.
What NT is crucial for making up and awareness? Where is this synthesized?
What about wakefulness?
NE. Locus coeruleus
Histamine - tuberomammilary
What NT is crucial for learning and memory? PLace it's made?
What about consciuosness and awwareness?
Ach - substantia nigra and VTA
What is derived from POMC?
Where arethe CBI receptors located and what do they recept? Fxn?
Where are CB2 receptors located?
Axons and presynaptic terminals in CNS and PNS. Recept Opiods - 2AG and anadaminde. Abundant GPCR
Decrease NT release by inhibiting adenylyl cyclase
- found on microglia. Big in anti-inflammation and bladder stuff.
What is the NMDA for?
What activates them?
What blocks the channel, what opens it?
For excitatory NTs
NMDA: CA INFLUX
Glutamate and aspartate activate them to activate Ca influx
Blocks: PCP and Mg
Opens: Glycine + glutamate/aspartate
What is the AMPA for?
What activates them?
Na/K; SODIUM INFLUX
These activate NMDA channels
What excitatory receptors are primary afferents and premotor?
Long- term changes in synaptic strength and learning, memory
Learning memory and motor?
What role does Nitric oxide play in excitation?
NMDA --> Calcium influx --> activates calcineurin --> activates Nitric Oxide synthase to make more NO from arginine
NO can then relax smooth muscle, increase edema, produce free radicals, and control cardiovascular and respiration.
What information runs through RAS?
all ascending sensory information is relayed through RAS,
uses glutamate to stimulate...
Ventral Pathway: the cortex and
Dorsal pathway: thalamus
Parabrachial nuclei complex's function is to?
Generate respiration patterns while awake... sometimes hyperventilation.
Vental only straight to cortex
What represents baseline cortical activity?
Excitatory amino acids, and also ACh
What is the PPT (pedunculopontine tegemental) and LDT (Laterodorsal nuclei)?
The arousal system that uses acetylcholine.
Dorsal and ventral
What pathway is the primary cause of wakefulness and REM sleep? What helps with REM and wakefulnes?
Arousal II, PPT/LDT with ACh
WHat is special about the Arousal III system - locus coeruleus?
Has ascending (dorsal and ventral pathways to cortex and thalamus from the RAS) but also descneding: sensory modulation called the dorsal noradrenergic bundle!
What pathway is crucial in startle and altering rsponses? What NT?
Locus Coerulus, Norepinephrine
What Arousal pathway is inc harge of quiet awareness, mood and affect, modulation of pain?
Arousal IV, Raphe nuclei = serotonin!
What arousal pathway is in charge of cognitive functions, motor activity, and emotion?
Ventral tegemental nuclei = DOPAMINE!
What does it mean to be in a persistent vegetative state?
Hyperpolarized all the tiiime.
What NT allows us to be aware?
NE and Serotonin
What NT allows us to be alert and have many cognitive functions?
A patient has lost sensation in his right lower
extremity. If there is a lesion in the pons, which of
the following is most likely to be true?
Lateral most portion of the left medial lemniscus
Remember that the arms and legs switch after the decussation; the lateral cuneatus becomes the medial in the medulla!
What lesion i associated with relfex bladder?
A pt presents with flaccid legs, patella and achilles DTRs of 0/4 and incontinence. Where is the lesion?
ABOVE S2 for bladder. L1
What lobe of the brain does higher order processing of visual information and learning and memory?
Pt presentswith down and out eye, what herniation may have occured?
Uncus goes under the tectorial notch
A pt presents with respiratory arrest upon a blow to the head. What is herniated and where?
Tonsillar herniation in the foramen magnum
A pt presents with a head injury, there are no lesions on MRI and the neuro exam is WNL. A few days later he is brought back into the ER. What hemorrhage?
What causes macular sparing?
Lesion in the visual cortex. So this is behind everything, all the way in the occipital lobe.
Trapezoid body originates from what structure?
Anterior portion of anterior cochlear nucleus
If lateral lemniscus gets cut, what results?
Bilateral hearing loss, worse in the left ear.
What ist he fxn of hte OCB?
Dampen sound from loud noises = olivocochlear bundle
The cerebral cortex layers are arranged oldest to youngest. Is I or VI older?
older - VI
The posterior pituitary comes from what, embryologically?
diencephalon, downgrowth of diencephalon!
Anterior from stomoedum, comes up from mouth
Pt presents with difficulty swallowing, talking, muscle weakness, + babinski. They are hyperrefelxive and spastic. They also have weakness, atrophy, and fasciculations
Their sensory is okay.
ALS Amyotrophic lateral sclerosis
Mix of UMN and LMN bc the degeneration of ventral horn and UMN tract
In what artery occulsions do you lose motor function?
anterior spinal --> gets lateral corticospinal tract
Lenticulospinal arteries --> Gets PLIC
MCA = gets somatosensory cortex
ACA = gets somatosensory cortex
Basilar = Quadriplegia, gets corticospinal and corticobulbar
A pt presents to the ER following a head injury. Upon examination he is A&Ox3. a few minutes later, there is a rapid mental decline. Dx?
Epidural hematoma = classic lucid interval followed by rapid mental decline.
What arteries are space occupying and therefore shift midline? What is the bleed like?
Bridging VEINS so takes a while to leak out. Caused from trauma
An epidural hematoma looks like what?
biconvex, does not cros suture lines.
what hemorrhage can happen in cases otehr than trauma?
Subdural hematoma, can happen from alcohol or old age. It's slow.
What is resopnsible for emotion of memory?
What nerve does sensory to throat, tongue, ear?
What cranial nerves do sensory to ear?
Facial = external
Vagus = external ear
Glossopharyngeal = inner ear
What is neuropil?
Fibrous intercellular network of cellular processes emerging from neurons anglial cells
What is nissl substance?
Bunch of stuff found in body of a neuron
Pt has throat and inner pain, what nerve?
However, upon palpation of the RUQ, when the patient takes a
deep breath it, there is sudden pain. what pain fibers?
C fibers, bc they do visceral
A pt presents with sensory loss and paralysis in the lower right limb. Dx?
Anterior cerebral artery. ANTERIOR DOES LEGS
POSTERIOR DOES ARMS
What pathway activates antigravity reflexes?
Pontine reticular pathway
A blockage of the median and lateral aperatures can cause what disease?
Arnold Chiari Malformation or Dandy Walker Cyst
A pt presents witha combination of infratentorial external hydrocephalus and internal hydrocephalus. What was this caused by, and do the ventricles hypertrophy?
Yes, ventricles hypertrophy.
Caused by meningitis.
What's the drainage of the spinal cord?
Internal venous plexus of Batson,
Biggest sensory density?
Lips and fingertips
The core of anuclei body receives what inputs? What about the outer shells?
Outer: Muscle spindles, joints, pacinian
Core; adapting afferents?
Arcuate lamina separates what?
VPL and VPM
Local circuit interneurons are excitatory or inhibitory?
which fibers innervate extrafulsa fibers?
Difference between rigidity and spastic paralysis
Rigidity: Non velocity dependant increase in resistance to passive motion in all directions
Spinal shock does what 2 things:
Gives you LMN Signs and Symptoms for a few weeks.
Also inhibits reflexes
In the occipital pole, what part of the retina is represented the most posteriorly and the largest?
What is the function of corticotectal fibrs?
Control LMN of CN III, IV, VI
Receive afferent from optic tract and LGN
Pretectal = intensity of light chagnes
Argyll Robertson pupil is what?
Pupil does not constrict under light reflex, bu it does under the accommodation reflex
What are the zones of the hypothalamus?
Medial preoptic = Neurons that make GnRH
Periventricular zone: Adjacent to 3rd ventricle, makes hormones for A pit
Medial Zone: Has tons of nuclei
Lateral Zone: Feeding center and medial forebrain bundle.
Mammilary has the mamillary bodies I think
What does the fornix arise from?
Subiculum (precommissural) and hippocampus (postcommissural)
Do the auditory tract
- AVCN --> VENTRAL ACOUSTIC STRIA/TRAPEZOID BODY --> Superior olivary nucleus, contralateral and ipsilaterally, and Inferior colliculus
- VPCN --> INTERMEDIATE ACOUSTIC STRIA --> Nucleus Lateral lemniscus and inferior colliculus
- DCN --> DORSAL ACOUSTIC STRIA --> Nucleus Lateral lemniscus and inferior colliculus
--> all this to medial geniculate body
What's the nucleus accumbens?
Addiction and chronic pain
in from amygdala and hippocalmpus, efferent to hypothalmus, and brainstem
draw the circuit of Papez
CIngulate gyrus --> entorhinal hippocampus --> mammillary body --> Anterior nucleus
Medial mamillary nuclei connects cingulate to entorhinal.
What is the subiculum?
What are teh afferents into the hypothalamus?
Efferents from hippocampus to form fornix
Afferents: Perforant pathway
CA3 --> CA1 --> Subiculum
What is the formation of hippocampus?
External layer is molecular
MIddle layer = granule and pyramidal
Inner layer = polymorphic