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338 Cards in this Set
- Front
- Back
What is derived from neuroectoderm?
(4) |
- CNS neurons
- ependymal cells (inner lining of ventricles --> make CSF) - oligodendroglia - astrocytes |
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What is derived from neural crest?
(2) |
- Schwann cells
- PNS neurons |
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What is derived from mesoderm?
(2) |
- microglia
- macrophages "Microglia, like Macrophages, originate from Mesoderm" |
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General info on Neurons?
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- comprise nervous system
- permanent cells --> do not divide in adulthood - large cells with prominant nucleoli - Nissl substance (RER) in cell body, dendrites, NOT axon |
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General info on Astrocytes?
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- physical support
- repair K+ metabolism - removal of excess NT - maintenance of blood-brain barrier - reactive gliosis in response to injury |
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What is the astrocyte marker?
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GFAP
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General info on Microglia?
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- CNS phagocytes
- mesodermal origin - not readily discernible in Nissl stains - have small, irregular nuclei and relatively little cytoplasm - microglia --(tissue damage--> large ameboid phagocytic cells |
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What happens to HIV-infected microglia cells?
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- they fuse to from multinucleated giant cell in the CNS
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General info on Oligodendroglia?
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- each one myelinates multiple CNS axons (up to 30 each)
- in Nissl stains, they appear as small nuclei with dark chromatin and little cytoplasm - predominant type of glial cell in white matter -resemble fried egg on H&E |
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What cells are destroyed in Multiple Sclerosis?
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Oligodendrocytes
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General info on Schwann cells?
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- each one myelinates only 1 PNS axon
- also promote axonal regeneration - derived from neural crest |
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What cells are destroyed in Guillain-Barre syndrome?
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Schwann cells
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Acoustic Neuroma?
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- type of schwannoma
- typically located in internal acoustic meatuc (CN VIII) |
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Free nerve endings types, location, function
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1. C -- slow, unmyelinated fibers
2. Aδ -- fast, myelinated fibers skin, epidermis, some viscera sense pain and temperature |
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Meissner's corpuscles general info, location, function
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- large, myelinated fibers
glabrous (hairless) skin sense position, dynamic touch, adapt quickly |
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Pacinian corpuscles general info, location, function
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- large, myelinated fibers
deep skin, ligaments, joints sense vibration and pressure |
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Merkel's disks general info, location, function
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- large, myelinated fibers
hair follicles position sense, static touch (sharp edges), adapt slowly |
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Endoneurium
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- invest single nerve fiber
- inflammatory infiltrate in Guillain-Barre |
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Perineurium
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- Permeability barrier
- surrounds a fascicle of nerve fibers - must be rejoined in microsurgery for limb reattachment |
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Epineurium
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- dense connective tissue that surrounds entire nerve (fascicles and blood vessels)
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NE and anxiety?
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- NE is INCREASED in anxiety
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NE and depression?
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- NE is DECREASED in depression
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Dopamine and schizophrenia?
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- dopamine is INCREASED in schizophrenia
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Dopamine and Parkinson's?
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- dopamine is DECREASED in Parkinson's (and depression)
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Dopamine and depression?
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- dopamine is DECREASED in depression (and Parkinson's)
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5-HT and anxiety?
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- 5-HT is DECREASED in anxiety (and depression)
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5-HT and depression?
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- 5-HT is DECREASED in depression (and anxiety)
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ACh and Alzheimer's?
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- ACh is DECREASED in Alzheimer's (and Huntington's and REM sleep)
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ACh and Huntington's?
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- ACh is DECREASED in Huntington's (and Alzheimer's and REM sleeep)
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ACh and REM sleep?
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- ACh is DECREASED in REM sleep (and Alzheimer's and Huntington's)
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GABA and anxiety?
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- GABA is DECREASED in anxiety (and Huntington's)
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GABA and Huntington's?
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- GABA is DECREASED in Huntington's (and anxiety)
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Where is NE synthesized?
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Locus ceruleus
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Where is dopamine synthesized?
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Ventral tegmentum and SNc
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Where is 5-HT synthesized?
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Raphe nucleus
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Where is ACh synthesized?
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Basal nucleus of Meynert
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Where is GABA synthesized?
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Nucleus accumbens
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What area of the brain makes NT in response to stress and panic?
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- Locus ceruleus --> NE
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What is the reward center, pleasure, addiction, fear center of the brain?
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Nucleus accumbens and Septal nucleus
|
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What NT are INCREASED in anxiety?
(1) |
- NE
|
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What NT are DECREASED in anxiety?
(2) |
- 5-HT
- GABA |
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What NT are DECREASED in depression?
(3) |
- NE
- dopamine - 5-HT |
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What NT are DECREASED in Parkinson's?
(1) |
- dopamine
|
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What NT are DECREASED in Alzheimer's?
(1) |
- Ach
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What NT are DECREASED in Huntington's?
(2) |
- ACh
- GABA |
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What NT are DECREASED in REM sleep?
(1) |
- ACh
|
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What 3 structures form the blood-brain barrier (BBB)?
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1. Tight junctions between nonfenestrated capillary endothelial cells
2. Basement membrane 3. Astrocyte processes |
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What crosses the BBB slowly by carrier-mediated transport mechanism?
(2) |
- glucose
- amino acids |
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What crosses the BBB rapidly via diffusion?)
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- nonpolar/lipid-soluble substances
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A few specialized brain regions with fenestrated capillaries and no BBB allow what?
(2) |
1. they allow molecules in the blood to affect brain function (ie. area postrema --> vomiting after chemo; OVLT --> osmotic sensing)
2. they allow neurosecretory products to enter circulation (ie. neurohypophysis --> ADH release) |
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What are the 3 blood barriers?
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1. blood-brain barrier
2. blood-testis barrier 3. maternal-fetal blood barrier of placenta |
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What does a brain infarction destroy in relation to the blood brain barrier? And what does this lead to?
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- endothelial cell tight junctions
- leads to vasogenic edema |
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What does the Hypothalamus do?
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"TAN HATS"
- Thirst and water balance - Adenohypophysis control - Neurohypophysis releases hormones from hypothalamus - Hunger - Autonomic regulation - Temperature regulation - Sexual urges |
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Inputs to the hypothalamus?
(2) |
- OVLT (senses change in osmolarity)
- area postrema (responds to emetics) |
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What makes ADH?
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Supraoptic nucleus
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Where is the supraoptic nucleus found?
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Hypothalamus
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What makes oxytocin?
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Paraventricular nucleus
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Where is the paraventricular nucleus found?
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Hypothalamus
|
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What does the lateral area of the hypothalamus do?
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controls hunger
destruction leads to anorexia, failure to thrive (infants) |
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What inhibits the lateral area of the hypothalamus?
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Leptin --> don't feel hungry
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What does the ventromedial area of the hypothalamus do?
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controls satiety
destruction leads to hyperphagia "If you zap your VENTROMEDIAL nucleus, your grow VENTRALLY and MEDIALLY" |
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What stimulates the ventromedial area of the hypothalamus ?
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Leptin --> feel full
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What does the Anterior hypothalamus control? And is it controlled via sympathetics or parasympathetics?
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- cooling
- pArasympathetic "Anterior nucleus = Cool off" (A/C = Anterior Cooling) |
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What does the posterior hypothalamus control? And is it controlled via sympathetics or parasympathetics?
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- heating
- sympathetic "posterior nucleus = get fired up" "If you zap your Posterior hypothalamus, you become a Poikilotherm (cold-blooded, like a snake)" |
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What does the Septal nucleus control?
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Sexual urgers
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Where is the septal nucleus located?
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Hypothalamus
|
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What does the suprachiasmatic nucleus control?
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Circadian rhythm
"You need SLEEP to be CHARISMATIC (chiasmatic)" |
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Where is the suprachiasmatic nucleus located?
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Hypothalamus
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What are all the areas of the hypothalamus and what do they do?
(8) |
1. Supraoptic nucleus -- makes ADH
2. Paraventricular nucleus -- makes oxytocin 3. Lateral area -- hunger 4. Ventomedial area -- satiety 5. Anterior hypo -- cooling 6. Posterior hypo -- heating 7. Septal nucleus -- Sexual urges 8. Suprachiasmatic nucleus -- circadian rhythm |
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Posterior pituitary aka?
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Neurohypophysis
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What does the posterior pituitary do?
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- receives hypothalamic axonal projections from supraoptic (ADH) and paraventricular (oxytocin) nuclei
|
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Anterior pituitary aka?
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Adenohypophysis
|
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Oxytocin
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- made by paraventricular nuclei of hypothalamus
- oxys = quick - tocos = birth |
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What does the Thalamus do?
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- major relay for ascending sensory information that ultimately reaches the cortex
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What does the Lateral geniculate nucleus (LGN) control?
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- visual, CN II
- projects via optic radiations to occipital cortex "Lateral for Lookin' " |
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Where is the lateral geniculate nucleus (LGN) located?
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Thalamus
|
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What does the Medial geniculate nucleus (MGN) control?
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- auditory
receives input from superior olive and inferior colliculus of tectum goes to auditory cortex of temporal lobe "Medial for Music" |
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Where is the medial geniculate nucleus (MGN) located?
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Thalamus
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What does the ventral posterior nucleus, lateral part (VPL) do?
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- body sensation (proprioception, pressure, pain, tough, vibration via dorsal columns, spinothalamic tract)
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Where is the ventral posterior nucleus, lateral part (VPL) located?
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Thalamus
|
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What does the ventral posterior nucleus, medial part (VPM) do?
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- facial sensation (via CNV) -> goes to primary somatosensory cortex
"You put Makeup on your face, and the sensory info is relayed through the VPM" |
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Where is the ventral posterior nucleus, medial part (VPM) located?
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Thalamus
|
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What does the ventral anterior/lateral (VA/VL) nuclei do?
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motor
"Motor is anterior to sensation in the thalamus, just like the cortex" |
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Where is the ventral anterior/lateral (VA/VL) nuclei located?
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Thalamus
|
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Blood supply to the thalamus?
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- posterior communicating artery
- posterior cerebral artery - ICA (anterior choroidal arteries) |
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What all does the LImbic system include?
(4) |
- cingulate gyrus
- hippocampus - fornix - mammillary bodies |
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What all is the Limbic system responsible for?
(5) |
"The Famous 5 F's"
- Feeding, Fighting, Fleeing, Feeling, and ******* |
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What info does the cerebellum receive?
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- receives CONTRAlateral cortical input via middle cerebellar peduncle
- receives IPSIlateral proprioceptive info via inferior cerebellar peduncle |
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What are the input nerves to the cerebellum?
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- climbing and mossy fibers
|
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What does the cerebellum do?
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- provides stimulatory feedback to CONTRAlateral cortex to modulate movement
|
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What are the output nerves from the cerebellum?
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- Purkinje fibers output to deep nuclei of cerebellum --> which in turn output to cortex via superior cerebellar peduncle
|
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What are the deep nuclei of the cerebellum?
|
Lateral to Medial:
- Dentate - Emboliform - Globose - Fastigial "Don't Eat Greasy Foods" |
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What does the lateral cerebellum control?
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- voluntary movement of extremities
|
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What does the medial cerebellum control?
|
- balance
- truncal coordination - ataxia - propensity to fall toward injured (IPSIlateral) side |
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In what areas is the basal ganglia important?
(2) |
- voluntary movements
- making postural adjustments |
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SNc
|
- Substantia nigra pars compacta
- part of the basal ganglia |
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SNr
|
- Substantia nigra pars reticulata
- part of the basal ganglia |
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GPe
|
- Globus pallidus externus
- part of the basal ganglia |
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GPi
|
- Glubus pallidus internus
- part of the basal ganglia |
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STN
|
- Subthalamic nucleus
- part of the basal ganglia |
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D1
|
- Dopamine D1 receptor
- excitatory "D1-R = D1Rect pathway" - part of the basal ganglia |
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D2
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- Dopamine D2 receptor
- inhibitory "Indirect = Inhibitory" - part of the basal ganglia |
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Excitatory pathway of the basal ganglia?
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Cortex (stimulates via glutamate) → Striatum (inhibits) → "SNr-GPi" complex (less inhibition of thalamus) → Thalamus (stimulates) → Cortex (stimulates) → Muscles, etc. → (hyperkinetic state)
- SNc's dopamine binds to D1 receptors in the excitatory pathway --> stimulating the excitatory pathway (increases motion) - therefore, loss of dopamine in Parkinson's inhibits the excitatory pathway (decreased motion) |
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Inhibitory pathway of the basal ganglia?
|
Cortex (stimulates) → Striatum (inhibits) → GPe (less inhibition of STN) → STN (stimulates) → "SNr-GPi" complex (inhibits) → Thalamus (is stimulating less) → Cortex (is stimulating less) → Muscles, etc. → (hypokinetic state)
- SNc's dopamine binds to D2 receptors in the inhibitory pathway --> inhibiting the inhibitory pathway (double negative) (increased motion) - therefore, loss of dopamine in Parkinson's excites (ie. disinhibits) the inhibitory pathway ( decreased motion) |
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What is Parkinson's disease?
|
- a degenerative disorder or CNS
|
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What is Parkinson's disease associated with (microscopically)?
(2) |
- Lewy bodies (composed of α-synuclein --> intacellular inclusion)
- depigmentation of the substantia nigra pars compacta (SNc) --> loss of dopaminergic neurons |
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Rare cases of Parkinson's disease have been linked to what?
|
- exposure to MPTP --> a contaminant in illicit street drugs
|
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What symptoms do you see in Parkinson's disease?
(4) |
"TRAP"
- Tremor (at rest -- ie. pill-rollong tremor) - cogwheel Rigidity - Akinesia - Postural instability "you are TRAPped in your body" |
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What is hemiballismus?
|
- sudden, wild flailing of 1 arm +/- leg
"Half ballistic (as in throwing a baseball)" |
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What is hemiballismus characteristic of?
|
- contralateral subthalamic nucleus lesion (ie. *lacunar stroke in pt. with a history of HTN*)
- loss of inhibition of thalamus through globus pallidus |
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What is Huntington's disease?
|
- an autosomal dominant trinucleotide repeat disorder
- expansion of CAG repeats (anticipation) "CAG = Caudate loses Ach and Gaba" |
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On what chromosome is the trinucleotide repeat found in Huntington's disease?
|
Chromosome 4
|
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What happens in Huntington's disease?
|
Neuronal death via:
- NMDA-R binding - glutamate toxicity |
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What symptoms do you see in Huntington's disease?
(3) |
- Chorea (quick movements of feet of hands)
- Depression - Progressive Dementia |
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When do symptoms manifest in Huntington's disease?
|
- between the ages of 20 and 50
|
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What do you see on MRI in Huntington's disease?
|
- atrophy of caudate nucleus (loss of GABA)
- atrophy of putamen - enlarged lateral ventricles - defined sulci |
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What is chorea?
|
- sudden, jerky, pruposeless movements (of hands and feet)
- Chorea = dancing (Greek) "Think choral dancing or choreography" |
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Chorea is characteristic of what?
|
- basal ganglia lesion (ie. Huntington's)
|
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What is athetosis?
|
- slow, writhing movements, especially of fingers
- Athetos = not fixed (Greek) "Think snakelike" |
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Athetosis is characteristic of what?
|
- basal ganglia lesion (ie. Huntington's)
|
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What is myoclonus?
|
- sudden, brief muscle contraction
- jerks, hiccups |
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What is dystonia?
|
- sustained, involuntary muscle contractions
- writer's cramp |
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What is an Essential/Postural tremor?
|
- action tremor (worsens when holding posture)
- autosomal dominant - essential trmor pts. often self-medicate with alcohol, which decreases tremor |
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What is the treatment for essential/postural tremor?
|
- β-blockers
|
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What is a Resting tremor?
|
- most noticeable distally
- seen in Parkinson's pts (pill-rolling tremor) |
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What is an Intention tremor?
|
- slow, zig-zag motion when pointing toward a target
- associated with cerebellar dysfunction |
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Cerebral Cortex functions:
Frontal Lobe (4) |
- Motor speech (Broca's area; dominant hemishpere)
- Frontal eye fields - Premotor area (part of extrapyramidal circuit) - Principle motor area |
|
Cerebral Cortex functions:
Parietal Lobe (1) |
- Principal sensory areas
|
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Cerebral Cortex functions:
Occipital Lobe (1) |
- Prnicipal visual cortex
|
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Cerebral Cortex functions:
Temporal Lobe (2) |
- Primary auditory cortex (Heschl's gyrus)
- Associative auditory cortex (Wernicke's area; dominant hemisphere) |
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What does the arcuate fasciculus connect?
|
- Wernicke's area (associative auditory complex) and Broca's area (motor speech)
|
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Frontal Lobe functions
(9) |
"Executive Functions"
1. planning 2. inhibition 3. concentration 4. orientation 5. language 6. abstraction 7. judgement 8. motor regulation 9. mood |
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What is most noticible symptom in frontal lobe lesions?
|
- lack of social judgement
"Damage = Disinhibition (ie. Phineas Gage)" |
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What is the homunculus?
|
- a topographical representation of sensory and motor areas in the cerebral cortex
|
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What is the homunculus used for?
|
- used to localize lesions (ie. in blood supply) leading to specific defects
- for example, lower extremity deficit in sensation or movement may indicate involvement of the anterior cerebral artery |
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Brain Lesion Consequences:
Amygdala (bilateral) (3) |
Kluver-Bucy syndrome:
- hyperorality - hypersexuality - disinhibited behavior associated with HSV-1 |
|
Brain Lesion Consequences:
Frontal Lobe (5) |
- contralateral spastic paresis
-disinhibition - deficits in concentration, orientation, and judgement - may have reemergence of primitive reflexes -can result in Broca's aphasia if dominant hemisphere |
|
Brain Lesion Consequences:
Right parietal lobe (1) |
- Spatial neglect syndrome (agnosia of the contralateral side of the world)
|
|
Brain Lesion Consequences:
Reticular activating system (midbrain) (1) |
- reduced levels of arousal and wakefulness (ie. coma)
|
|
Brain Lesion Consequences:
Mammillary bodies (bilateral) (6) |
Wernicke-Korsakoff syndrome
- Wernicke --> confusion, ophthalmoplegia, ataxia, can be secondary to thiamine deficiency - Korsakoff --> memory loss, confabulation, personality changes |
|
Brain Lesion Consequences:
Basal ganglia (3) |
- tremor at rest
- chorea - athetosis |
|
Brain Lesion Consequences:
Cerebellar hemisphere (2) |
- intention tremor
- limb ataxia - damage to the cerebemmum results in IPSI deficits - fall toward side of lesion - cerebellum --> SCP --> contralateral cortex --> corticospinal decussation = IPSI "Cerebellar hemispheres are LATERALLY located --> affect LATERAL limbs" |
|
Brain Lesion Consequences:
Cerebellar vermis (2) |
- truncal ataxia
- dysarthria "Vermis is CENTRALLY located --> affects CENTRAL body" |
|
Brain Lesion Consequences:
Subthalamic nucleus (1) |
- CONTRA hemiballismus
|
|
Brain Lesion Consequences:
Hippocampus (1) |
- anterograde amnesia (inability to make new memories)
|
|
Brain Lesion Consequences:
Paramedian pontine reticular formation (PPRF) (1) |
- eyes look AWAY from side of lesion
|
|
Brain Lesion Consequences:
Frontal eye fields (1) |
- eyes look TOWARD lesion
|
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What symptoms do you see in Central Pontine Myelinolysis?
(5) |
- acute paralysis
- dysarthria - dysphagia - diplopia - loss of consciousness |
|
What commonly causes Central Pontine Myelinolysis?
|
- very rapid correction of hyponatremia
|
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What happens with a recurrent laryngeal nerve injury?
|
- loss of all laryngeal muscle except cricothyroid
|
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What symptom do you see in recurrent laryngeal nerve injury?
|
- hoarseness
|
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What is aphasia?
|
- higher-order inability to speak
|
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What is dysarthria?
|
- motor inability to speak
|
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What is Broca's aphasia?
|
- NONFLUENT aphasia with intact comprehension
"BROca's BROken BOCA" left MCA superior division most often produces lesion |
|
Where is Broca's area?
|
- inferior frontal gyrus of frontal lobbe
|
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What is Wernicke's aphasia?
|
- FLUENT aphasia with impaired comprehension
"Wernicke's is Wordy but makes no sense!" "Wernicke's = What?" left MCA inferior division most often produces lesion |
|
Where is Wernicke's area?
|
- superior temporal gyrus of temporal lobe
|
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What is global aphasia?
|
- NONFLUENT aphasi with impaird comprehension
- BOTH Broca's and Wernicke's areas affected |
|
What is conduction aphasia?
|
- poor repetition but FLUENT speech
- intact comprehension - Arcuate fasciculus -- connects Broca's and Wernicke's areas |
|
What does the anterior cerebral artery supply?
|
- supplies anteromedial surface
|
|
What does the middle cerebral artery supply?
|
- supplies lateral surface
|
|
What does the posterior cerebral artery supply?
|
- supplies posterior and inferior surfaces
|
|
Associated area/deficit for:
Anterior spinal artery (3) |
Medial medullary syndrome
- CONTRA hemiparesis (lower extremities) - medial lemniscus (decreased CONTRA proprioception) - IPSI paralysis of hypoglossal nerve |
|
Associated area/deficit for:
PICA (12) |
Lateral medullay syndrome (aka Wallenberg's)
Nucleus ambiguous (CN IX, X, XI): IPSI paralysis of larynx, pharynx, palate -> dysarthria, dysphagia, loss of gag reflex Spinal V- ipsilateral pain and temperature of face Spinothalamic tract: CONTRA pain/temperature of body Descending hypothalamics: IPSI Horner syndrome - vertigo - diplopia - nystagmus - vomiting - IPSI ataxia |
|
Associated area/deficit for:
AICA |
Lateral inferior pontine syndrome
Facial nucleus and fibers: IPSI facial paralysis, loss of anterior 2/3 taste, lacrimation, salivation and corneal reflex, hyperacusis Spinal trigeminal nucleus/tract: ipsilateral pain/temperature (face) Contralateral pain/temperature loss body, middle cerebellar peduncle: ipsilateral ataxia vestibular nuclei: vertigo, nystagmus Ipis horner's |
|
Associated area/deficit for:
Posterior cerebral artery (1) |
- CONTRA homonymous hemianopia with macular sparing
- supplies occipital cortex |
|
Associated area/deficit for:
Middle cerebral artery (3) |
- CONTRA face and arm paralysis and sensory loss
- aphasia (dominant sphere) - left-sided neglect (nondominant lesion) |
|
Associated area/deficit for:
Anterior cerebral artery (2) |
- supplies medial surface of the brain
- leg-foot area of motor and sensory cortices |
|
Associated area/deficit for:
Anterior communicating artery (1) |
- lesion may cause visual field defects
|
|
What is the most common site of circle of Willis aneurysms?
|
Anterior communicating artery
|
|
Associated area/deficit for:
Posterior communicating artery (3) |
- common area of aneurysm
- causes CN III palsy - "down and out" |
|
Associated area/deficit for:
Lateral striate (4) |
- divisions of middle cerebral artery
Supplies: - internal capsule - caudate - putamen - globus pallidus "Arteries of Stroke" |
|
An infarct of the posterior limb of the internal capsule causes what?
|
- pure motor hemiparesis
|
|
Associated area/deficit for:
Watershed zones (2) |
Between:
- anterior cerebral / middle cerebral - posterior cerebral / middle cerebral |
|
Damage to watershed zones in severe hypotension leads to?
|
- upper leg / upper arm weakness
- defects in higher-order visual processing |
|
Associated area/deficit for:
Basilar artery (1) |
- infarct causees "locked-in syndrome"
- CN III is typically intact |
|
Associated area/deficit for:
in general, stroke of anterior circle (2) |
- general sensory and motor dysfunction
- aphasia |
|
Associated area/deficit for:
in general, stroke of posterior circle (4) |
Cranial nerve deficits
- vertigo - visual deficits - coma - cerebellar deficits (ataxia) - Dominant hemisphere --> ataxia - Nondominant hemisphere --> neglect |
|
Where do Berry aneurysms occur?
|
- at the bifurcations in the circle of Willis
|
|
Most common site of Berry aneurysms?
|
- the bifurcation of the anterior communicating artery
|
|
Most common complication of Berry aneurysms and what that leads to?
|
- Rupture --> leads to hemorrhagic stroke/subarachnoid hemorrhage
|
|
What diseases/syndromes are Berry aneurysms associated with?
(3) |
- adult polycystic kidney disease
- Ehlers-Danlos syndrome - Marfan's syndrome |
|
Other risk factors for Berry aneurysms?
(4) |
- advanced age
- HTN - smoking - race (higher risk in blacks) |
|
What are Charcot-Bouchard microaneurysms associated with?
|
- chronic HTN
|
|
What do Charcot-Bouchard microaneurysms affect?
|
- small vessels (ie. in basal ganglia, thalamus)
|
|
Epidural hematoma
|
rupture of midle meningeal artery, often 2ndary to fracture of temporal bone
*lucid interval" rapid expansion -> transtentorial herniation CNIII palsy CT shows "biconvex disk" not crossing duture lines, flax, tentorium |
|
Subdural hematoma
|
rupture of bridging veins-> slow venous bleeding
seen in elderly individuals, alcoholics, blunt trauma, shaken baby (brain atrophy, shaking, whiplash) crescent shaped hemorrhage that crosses suture lines, midline shift, gyri preserved, does not cross flax, tentorium |
|
Subarachnoid hemorrhage
|
rupture of aneurysm (Berry), or AVM
rapid time course, "worse headache of my life" bloody or yellow spinal tap 2-3 days afterward has risk of vasospasm due to blood breakdown (treat with nimodipine), and rebleed -> ischemia |
|
Intraparenchymal (HTNsive) hemorrhage
|
most often systemic HTN, but also amyyloid angiopathy (Alzheimer's), vasculitis (DM), and neoplasm
typically in basal ganglia and internal capsule |
|
Ischemic brain disease
|
irreversible damage after 5 minutes - most vulnerable hippocampus, neocortex, cerebellum, *watershed areas*
|
|
Atherosclerosis in ischemic brain disease
|
thrombi lead to ischemic stroke -> subsequent necrosis
cystic cavity with reactive gliosis |
|
Hemorrhagic stroke in ischemic brain disease
|
intracerebral bleeding, often due to HTN, anticoagulation and cancer
2ndary to ischemic stroke: reperfusion of ischemic/damaged vessels |
|
Ischemic stroke
|
emboli block large vessels, etiologies include A fib, carotid dissection, patent foraen ovale, endocarditis
lacunar strokes block small vessels, may be sndary to HTN tPA within 4.5 hours |
|
Transient ischemic attack
|
brief, reversible episode of neurologic dysfunction lasting fewer than 24 hours
|
|
Dural venous sinuses
|
cerebral veins -> venous sinuses -> internal jugular vein
|
|
Ventricular system
|
CSF made by choroid plexus, reabsorbed by venous sinus arachnoid granulations
lateral ventricles -> foramen of Monro/ventricular Foramen -> third ventricle -> cerebral aqueduct -> 4th ventricle -> subachnoid space (Lateral Foramina of Luschka, Medial foramen of Magendie) |
|
Normal pressure hydrocephalus
|
Dementia, ataxia and urinary incontinence "Wet, wobbly, and wacky"
reversible cause of dementia in elderly Increases subarachnoid volume but not CSF pressure-> distortion of corona radiata |
|
Communicating hydrocephalus
|
decreased CSF reabsorption by arachnoid villi -> increased intracranial pressure, papilledema, herniation
|
|
Obstructive (noncommunicating) hydrocephalus
|
caused by a structural blockage of CSF circulation
|
|
Hydrocephalus ex vacuo
|
increase of CSF due to atrophy without an increase in pressure/damage
|
|
Spinal nerves
|
8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal
Nerves C1-C7 exit above corresponding vertebra - all others below |
|
Dorsal column
|
ascending pathway for fine touch, proprioception, vibration, pressure
receptor from body -> neuron body in DRG -> travels ipsilateral until synapsing in lower medulla -> decussates as internal arcuate fibers -> ascends as medial lemniscus -> synapses in VPL of thalamus -> 3rd order neuron goes to somatosensory cortex Gracile fasciculus from lower extremities to gracile nucleus Cuneate fasciculus from upper extremities to cuneate nucleus ordered as you are with hands at sides -arms on outside, legs inside |
|
Lesions in dorsal column
|
in spinal cord -> ipsilateral loss of function
above decussation (medulla) -> contralateral |
|
Anterolateral/spinothalamic tract
|
ascending pathway for pain and temperature
1st neuron has cell body in DRG -> synapses in dorsal horn of spinal cord -> 2nd neuron immediately decussates -> ascends in lateral spinothalamic tract -> synapses in VPL -> 3rd neuron -> somatosensory cortex Legs are lateral |
|
Lesions in anterolateral/spinothalamic tract
|
contralateral loss of function
|
|
Lateral corticospinal tract
|
descending voluntary movement
Cortex -> posterior limb of internal capsule -> crus cerebri (midbrain) -> base of pons -> pyramids (medulla) -> pyramidal decussation -> lateral spinal corticospial tract -> ventral horn synapse -> muscle cortex -> ventral horn = upper motor neuron ventral horn -> muscle = lower motor neuron |
|
Upper motor neuron lesion
|
everything is turned up
spastic paralysis, increased muscle tone, diuse atrophy, hyperreflexia, Babinski (toes go UP), clasp knife spasticity |
|
Lower motor neuron lesions
|
everything is lowered
flaccid paralysis, hypotonia, muscle atrophy, hyporeflexia, no Babinski |
|
Poliomyelitis
|
caused by polio virus -> oropharynx/small intestine symptoms -> travel to anterior horn of spinal cord -> LMN destruction
symptoms: malaise, headache, fever, nausea, abdominal pain, sore throat, LMN lesions CSF with lymphocytic pleocytosis with slightly elevated protein, no change in glucose virus present in stool/throat |
|
Werdnig-hoffman disease
|
infantile spinal muscular atrophy: "floppy baby," tongue fasciculations, median death at 7 months
degeneration of anterior horns, LMN involvement AR |
|
Amyotrophic lateral sclerosis
|
both LMN and UMN signs; no sensory, cognitive, or oculomotor deficits
presents as fasciculations-> atrophy; progressive and fatal can be caused by superoxide dismutase 1 defect Riluzole can lengthen survival by decreasing presynaptic glutamate release |
|
Tabes dorsalis
|
degeneration of dorsal columns and dorsal roots due to tertiary syphilis -> impaired proprioception and locomotor ataxia
Charcot's joints, shooting pain, Argyll Robertson pupil, absent DTRs, positive Pomberg, sensory ataxia at night (dark) |
|
Friedreich's ataxia
|
AR trinucleotide repeat: GAA -> frataxin (mitochondria function)
staggering gait, frequent falling, nystagmus, dysarthria, pes cavus, hammer toes, hypertrophic cardiomyopathy (death) kids with kyphoscoliosis Friedreich is Fratastic, he pledged GAA and is always stumbling, staggering, falling |
|
Brown-Sequard Syndrome
|
hemisection of spinal cord
1. ipsilateral UMN signs below lesion (corticospinal tract) 2. Ipsilateral fine touch, vivration, proprioception below lesion (dorsal column) 3. contra pain and temperature loss below (spinothalamic tract) 4. Ipsilateral loss of all sensation at level 5. LMN signs at level of lesion |
|
Horner's syndrome
|
1. Ptosis (superior tarsal muscle) 2. Anhidrosis 3. Miosis
loss of sympathetic innervation Pathway: hypothalamus -> intermediolateral column 0> superior cervical ganglion -> pupil, smooth muscle of eyelids, sweat glands |
|
Reflexes
|
Biceps = C5
Triceps = C7 Patella = L4 Achilles = S1 |
|
Mororeflex
|
"hang on for life" abduct/extend limbs when startled then draw together - normal disappear with 1st year
|
|
Rooting reflex
|
movement of head toward one side if cheek or mouth stroked (nipple seeking)
|
|
Sucking reflex
|
sucking response when roof of mouth is touched
|
|
Palmar reflex
|
curling of fingers when palm stroked
|
|
Babinski reflex
|
dorsiflexion of large toe and fanning of other toes with plantar reflex
up with UMN lesion |
|
Gallant reflex
|
stroking one side of the spine while newborn in ventral suspension causes lateral flexion of lower body towards stimulated side
|
|
Pineal gland
|
melatonin secretion - circadian rhythms
|
|
Superior colliculi
|
conjugate vertical gaze center
lesion cause Parinaud syndrome - paralysis of conjugated gaze, can be due to pinealoma |
|
Inferior colliculi
|
auditory
|
|
Cranial nerves
|
On Old Olympus's Towering Tops A Finn And German Viewed Some Hops
Olfactory, Optic, Oculomotor, Trochlear, Trigeminal, Abducens, Facial, Auditory vestibular (vestibulocochlear) Glossopharyngeal, Vagus, (Spinal) Accessory, Hypoglossal |
|
CN I
|
olfactory nerve- smell
projections through cribriform plate |
|
CN II
|
optic nerve
sight exits through optic canal |
|
CN III
|
Eye movements (SR, IR, MR, IO), pupillary constriction (PS: E-W nucleus, muscarinic R). accommodation, eyelid opening
exits through superior orbital fissure |
|
CN IV
|
eye movement (SO)- downward gaze when eye is fully adducted (looking at nose)
exits through superior orbital fissure |
|
CN V
|
Trigeminal
mastication, facial sensation (opthalmic, maxillary, mandibular division) V1 branch exits through superior orbital fissure V2 exits through foramen rotundum V3; foramen ovale |
|
CN VI
|
Eye movement (LR)
exits through superior robital fissure |
|
CN VII
|
Facial nerve
facial movement, taste anterior 2/3 tongue, lacrimation, salivation, eyelid closing, stapedius muscle in ear (dampens sound) exits through auditory canal (stylomastoid foramen) |
|
CN VIII
|
vestibulocochlear
hearing and balance exits through auditory canal |
|
CN IX
|
glossopharyngeal
taste from posterior 1/3 tongue, swallowing, salivation (parotid), carotid body and sinus chemo/baroreceptors, and stylopharyngeus (elevates pharynx, larynx) exits through jugular foramen |
|
CN X
|
vagus
swallowing, palate elevation, midline uvula, talking, coughing, thoracoabdominal viscera, arotic arch chemo/baroreceptors exits through jugular foramen |
|
CN XI
|
spinal accessory nerve
head turning, shoulder shrugging exits through jugular foramen (enters skull through foramen magnum) |
|
CN XII
|
hypoglossal
tongue movement exits through hypoglossal foramen (canal) |
|
Cranial nerve nuclei in midbrain
|
CN III, IV
|
|
Cranial nerves nuclei in pons
|
CN V, VI, VII, VIII
|
|
Cranial nerve nuclei in pmedulla
|
CN IX, X, XI, XII
|
|
Corneal reflex
|
afferent V1 ophthalmic (nasociliary branch)
efferent VII (temporal branch : orbicularis oculi) |
|
Lacrimation reflex
|
afferent V1, efferent VII
|
|
Jaw jerk reflex
|
V3 sensory from masseter
V3 motor to masseter |
|
Pupillary reflex
|
afferent II, efferent III
|
|
Gag reflex
|
afferent IX, efferent IX, X
|
|
Vagal nucleus Solitarius
|
visceral sensory information (taste, baroreceptors, gut distention) for CN VII, IX, X
|
|
Vagal nucleus ambiguus
|
motor innervation of pharynx, larynx and upper esophagus, CN IX, X, XI
|
|
Vagal dorsal motor nucleus
|
parasympathetic fibers to heart, lungs, and upper GI
|
|
Optic canal
|
CN II, ophthalmic artery, central retinal vein
|
|
Superior orbital fissure
|
CN III, IV, V1, VI, ophthalmic vein, sympathetic fibers
|
|
Foramen rotundum
|
CN V2
|
|
Foramen Ovale
|
CN V3
|
|
Foramen spinosum
|
middle meningeal artery
|
|
internal auditory meatus
|
CN VII, VIII
|
|
jugular foramen
|
CN IX, X, XI, jugular vein
|
|
Hypoglossal canal
|
CN XII
|
|
Foramen magnum
|
spinal roots CN XI, brain stem, vertebral arteries
|
|
Cavernous sinus
|
venous sinuses on either side of pituitary
blood from eye and superficial cortex -> cavernous sinus -> internal jugular vein CN III, IV, V1, V2, and VI, and postganglionic sympathetic fibers to the orbit all pass through here cavernous portion of internal carotid artery is also here |
|
Cavernous sinus syndrome
|
ophthalmoplegia, ophthalmic and maxillary sensory loss
|
|
Danger triangle of face
|
edges of mouth to bridge of nose
potential for an infection to spread from here (ex. upper lip) to the brain via venous drainage facial vein -> ophthalmic veins -> cavernous sinus |
|
CN XII LMN lesion
|
tongue deviated towards side of lesion due to weakened muscles on affected side
|
|
CN V motor lesion
|
jaw deviates toward side of lesion due to unopposed force from opposite pterygoid muscle
|
|
CN X lesion
|
uvula deviates away from side of lesion - weak side collapse and uvula pulled away
|
|
CN XI lesions
|
weakness of turning head to contralateral side, shoulder droop on same side
|
|
Conductive hearing loss
|
abnormal Rinnne test (bone > air); Weber localizes to affected ear
|
|
Sensorineual hearing loss
|
normal Rinne test (air > bone); Weber test localizes to unaffected ear
|
|
Facial nerve UMN lesion
|
motor cortex or connection between cortex and facial nucleus
contralateral paralysis of lower face only; bilateral UMN innnervation of upper face |
|
Facial nerve LMN lesion
|
Ipsilateral paralysis of upper and lower face
|
|
Bell's palsy
|
complete destruction of facial nucleus itself or its brachial efferent fibers
peripheral ipsilateral facial paralysis with inability to close eye on involved side idiopathic -most recover other causes: AIDS, Lyme disease, HSV, Sarcoidosis, Tumors, Diabetes |
|
Muscles of mastication
|
3 muscles close: masseter, temporalis, medial pterygoid
1 opens: lateral pterygoid all are innervated by trigeminal nerve V3 |
|
Retinitis
|
retinal necrosis + edema = atrophic scar
associated with CMV in AIDS patients |
|
Iritis
|
due to systemic inflammation
|
|
Near vision
|
ciliary muscle contracts (zonular gibers relax -> lens relaxes -> more convex)
can't see far away |
|
Distant vision
|
ciliary muscle relaxes (lens flattens)
can't see up close |
|
Aging of eye
|
sclerosis and decreasing elasticity causes presbyopisa (no near vision)
|
|
Retinal artery occlusion
|
acute painless monocular loss of vision, pale retina and cherry-red macula (own blood supply -choroid artery)
|
|
Open/wide angle glaucoma
|
obstructed outflow (eg. Canal of Schlemm); myopia, increases with aging, African-American race
most often "silent" painless |
|
Closed/narrow angle glaucoma
|
contact between lens and central iris forms seal - flow of normal fluid behind pupil messed up
very painful, impaired vision, rock-hard eye, frontal headache, ophthalmologic emergency do not give epinephrine |
|
Cataract
|
painless, bilateral opacification of lens - impaired vision
risk: age, smoking, EtOH, sunlight, classic galactosemia, galactokinase deficiency, DM, trauma, infection, steroids |
|
Papilledema
|
increased intracranial pressure -> elevated optic disk with blurred margins-> blind spot
|
|
Pupillary constriction
|
pupillary spincter muscle (circular muscle), parasympathetic
CN III from Edinger-Westphal nucleus -> ciliary ganglion |
|
Pupillary dilation
|
radial muscle (pupillary dilater muscle), sympathetic
T1 preganglionic sympathetic -> superior cervical ganglion -> postganglionic sympathetic -> long ciliary nerve |
|
Pupillary light reflex
|
retina -> CN II -> pretectal nuclei in midbrain -> bilateral activation of E-W nucleui -> pupils contract bilaterally
Marcus gun pupil -> afferent pupillary defect -> decreased bilateral constriction when shone light in affected eye |
|
Retinal detachment
|
separation of neursensory layer of retina from pigment epithelium -> degeneration of photoreceptors -> vision loss
|
|
Age-related macular degeneration
|
loss of central vision (scotomas)
dry/atrophic is slow. due to fat deposits wet is rapid, due to neovascularization |
|
Right anopia
|
lesion in optic nerve before optic chiasm
|
|
bitemporal hemianopia
|
lesion/compression in optic chiasm
located near pituitary gland, often from tumor |
|
Contralateral homonymous hemianopia
|
lesions of optic tracts, can occur after optic chiasm, both temporal and parietal optic radiations, lateral geniculate nucleus
uncommon |
|
Contralateral superior quantrantopia
|
"pie in the sky"
temporal lobe lesions often from MCA inferior division infarct interrupting lower optic radiations through temporal lobe, lower bank of calcarine fissure |
|
Contralateral inferior quantrantopia
|
"pie on the floor"
MCA superior lesion infarct in the parietal lobe takes out upper optic radiations PCA infarct takes out primary visual cortex, upper calcarine bank |
|
Macular sparing
|
it's a thing
|
|
Meyer's loop
|
inferior retina -> loops around inferior horn of lateral ventricle
dorsal optic radiation - superior retina, takes shortest path via internal capsule |
|
Internuclear ophthalmoplegia
|
lesion in medial longitudinal fasciculus -> medial rectus palsy on attempted lateral gaze
nystagmus in abducting eye convergence normal seen commonly in MS |
|
Dementia
|
a decline in cognitive ability, memory, or function with intact consciousness
|
|
Alzheimer's disease
|
most common cause of dementia in elderly, Down's syndrome patients have increased risk
Familial form (10%) early onset: APP (on chromosome 21), presenilin-1 (14), presenilin-2 (1) later onset: ApoE4 (19) ApoE2 is protective widespread cortical atrophy: decreased ACh senile plaques: extracellular beta-amyloid core, amyloid angiopathy -> intracranial hemorrhage neurofibrillary tangles: intracellular, abnormally phosphorylated tau protein = insoluble cytoskeletal elements, correlate with degree of dementia |
|
Pick's disease
|
frontotemporal dementia: dementia, aphasia, parkinsonian aspects, change in personality (temper, mean)
spares parietal lobe and posterior 2/3 superior temporal gyrus Pick bodies: intracellular, aggregated tau protein frontotemporal atrophy |
|
Lewy body dementia
|
Parkinsonism with dementia and hallucinations
alpha-synuclein defect |
|
Creutzfeldt-jakob disease
|
rapidly prgressive (weeks to months) dementia with myoclonus
spongiform cortex prions -PrPc -> PrPsc sheet resistant to proteases |
|
Multiple sclerosis
|
autoimmune inflammation and demyelination of CNS, optic neuritis; relapsing/remitting neuro symptoms separated by time and location
increased IgG protein in CSD, oligoclonal bands are diagnostic MRi shoes periventricular plaques ts: beta-interferon, immunosuppression, symptomatic |
|
Guillain-Barre syndrome
|
bilateral ascending muscle weakness, facial paralysis in 50% of cases, autonomic function can be compromised
majority of patients recover completely after weeks to months associated with infections -> autoimmune attack of peripheral myeline due to molecular mimicry: C. jejuni, herpesvirus, inoculations and stress increased CSF protein with normal cell count tx: respiratory support, plasmapheresis, IV IG |
|
Progressive multifocal leukoencephalopathy
|
demyelination of CNS due to destruction of oligodendrocyte-> rapidly progressive, often fatal
associated with JC virus in AIDS patients |
|
Acute disseminated encephalomyelitis
|
multifocal perivenular inflammation and demyelination after infection (chickenpox, measles) or certain vaccinations (rabies, smallpox)
|
|
Metachromatic leukdystrophy
|
AR lysosmal storage disease, most commonly arylsulfatase A deficiency, build up of sulfatides leads to impaired production of myelin sheath
ataxia, dementia |
|
Charcot-Maire-Tooth disease
|
hereditary motor and sensory neuropathy: defective production of proteins invovled in structure and function or peripheral nerves or the myelin sheath
|
|
Partial seizures
|
localized to 1 area of the brain, most often from medial temporal lobe, ex. will just have one arm spasm
often has aura (smells, vision changes) can secondarily generalize simple partial - conciousness intact: motor, sensory, autonomic, psychic complex partial (impaired consciousness) |
|
Generalized seizures
|
more common than partial
1. absence - no postictal confusion, blank stare for a few seconds 2. Myoclonic - quick, repetitive jerks 3. tonic-clonic - alternating stiffening movement 4. tonic - stiffening 5. Atonic - "drop" seizures, commonly mistaken for fainting |
|
Status epilepticus
|
recurring seizures without restoration of consciousness
requires benzodiazepines emergently then antiepileptics |
|
Causes of seizures in children
|
genetic, infection (febrile), trauma, congenital, metabolic
|
|
Causes of seizures in adults
|
tumors, trauma, stroke, infection
|
|
Causes of seizures in elderly
|
stroke, tumor, trauma, metabolic, infection
|
|
Treatment of seizures for pregnant women
|
phenobarbital
|
|
Migraine
|
unilateral heache, 4-72 hours, pulsating pain with nausea, photophobia, phonophobia, +/- aura
irritation of CN V and release of substance P, GCRP, vasoactive peptides tx: propranolo, NSAIDs, sumatriptan for acute migraines |
|
Tension headache
|
unilateral; repetitive brief headaches, no photphobia, phonophobia, aura
|
|
Cluster headaches
|
unilateral, repetitive brief headaches, characterized by periorbital pain, ipsilateral lacrimation, rhinorrhea, Horners syndrome
males>>females tx: inhaled O2, sumatriptan |
|
Vertigo
|
illusion of movement,
peripheral- more common, inner ear etiology, postitional testing shows delayed horizontal nystagmus central vertigo - brain stem or cerebellar lesion, positional testing shows immediate nystagmus in any direction, may change directions |
|
Meniere's diseae
|
abrupt recurrent attacks of vertigo with deafness or tinnitus, unilateral, N/V
|
|
Sturge-Weber syndrome
|
congenital disorder with port-wine stains, typically in V1 ophthalmic distribution, ipsilateral leptomenigeal angiomas, pheochromocytomas
can cause glaucoma, seizures, hemiparesis, mental retardation occurs sporadically |
|
Tuberous sclerosis
|
HAMARTOMAS: hamartomas in CNS and skin, Adenoma sebaceum (cutaneous angiofibromas), Mitral Regurg, Ash-leaf spots, cardiac Rhabdomyoma, Tuberous sclerosis, autosomal dOminant, Mental retardation, renal Angiomyolipoa, Seizures
|
|
Neurofibromatosis type I
|
cafe-au-lait spots, Lisch nodules (pigmented iris hamartomase), neurofibromas in skin, optic gliomas, pheochromocytomas
AD with 100% penetrance but variable expression mutated NF-1 gene on chromosome 17 (negatively regulates RAS pathway) |
|
von Hippel-Lindau disease
|
cavernous hemangiomas in skin, mucosa, organs, bilateral renal cell carcinoma, hemangioblastoma in retina, brain stem, cerebellum, pheochromocytomas
AD, mutated tumor suppresor CHL on Chr3 |
|
Majority of adult primary tumors are ____
|
supratentorial
|
|
Majority of adult primary tumors are ____
|
infratentorial
infant-tentorial |
|
Most common type of brain tumor
|
metastases: well circumscribed, present at gray-white junction
|
|
Glioblastoma
|
most common primary brain tumor with poor prognosis <1 yrs
cerebral hemispheres can cross corpus callosum astrocytes stain for GFAP "pseudopalisading" pleomorphic tumor cells, borer central areas of necrosis and hemorrhage |
|
Meningioma
|
second most common primary brain tumor
often occurs in convexities of hemispheres and parasagittal region arises from arachnoid cells external to brain usually benign and resectable plindeled cells concentrically arranged in a whorled pattern, psammoma bodies (laminated calcifications) |
|
Schwannoma
|
Schwann cell origin
often localized to CN VIII, cerebellopontine angle resectable, S-100 positive bilateral in NF-2 |
|
Oligodendroglioma
|
relatively rare, slow growing
most often in frontal lobes -> personality changes, seizures, temper chicken wire capillary pattern oligodendroctyes: "fried egg" cells - round nuclei with clear cytoplasm often calcified |
|
pituitary adenoma
|
most commonly prolactinoma; bitemporal hemianopia
hyper/hypopituitarism |
|
Pilocytic astrocytoma
|
low grade, well circumscribed, in kids
most often found in posterior fossa may be supratentorial, GFAP positive benign, good prognsis Rosenthal fibers -eosinophilic, corkscrew fibers cystic and solid |
|
Medulloblastoma
|
kids: highly malignant cerebella tumor
form of primitive neuroectodermal tumor can compress 4th ventricle small blue cells, radiosensitive, homer-wright rosettes |
|
Ependymoma
|
kids: ependymal cell tumors most often in 4th ventricle
poor prognosis, kids characteristic perivascular pseudorosettes, rod-shaped blepharoplasts (basal ciliary bodies) found near nucleus |
|
Hemangioblastoma
|
kids
most often cerebellar, assoicated with von H-L syndrome when with retinal ngiomas can produce EPO -> polycythemia foamy cells and high vascularity |
|
Craniopharyngioma
|
kids
benign, confused with pituitary adenoma most common childhood supratentorial tumor remnants of Rathke's pouch, tooth enamle-like calcifications |
|
Uncal herniation
|
ipsilateral dilated pupils/ptosis - stretching of CNIII
contralateral homonymous hemianopia - compression of ipsilateral cerebral artery ipsilateral paresis- compression of contralateral crus cerebria (Kernohan's notch) Duret hemorrhages - paramedian artery rupture - caudal displacement of brain stem |
|
Ring-enhancing lesions
|
metastases (lung>breast>kidney>melanoma>GI), abscesses, toxoplamosis, primary CNS lymphoma
|
|
Uniformly enhancing lesions
|
metastaic lymphoma, meningioma, mets
|
|
Heterogeneously enhancing lesion
|
glioblastoma multiforme
|