Term
| The cerebellum is involved in which of the following - fine motor control, postural control, eye movements, balance? |
|
Definition
|
|
Term
| True or False: cerebellar dysfunction leads to impairment of executive functions (planning, reasoning) and personality changes. |
|
Definition
|
|
Term
| T or F: The systematic, uniform structure of the cerebellar cortex suggests that it performs the same fundamental operation. |
|
Definition
|
|
Term
| What cell type in the cerebellar cortex is the only output signal cell? |
|
Definition
| Purkinje cell, which then sends signals to deep nuclei (dentate) for output |
|
|
Term
| What is the function of the cerebrocerebellum versus the spinocerebellum (vermis) and vestibulocerebellum (nodulus and floculous)? |
|
Definition
| Cerebro - coordination of voluntary movements and cognitive control; Vermis and Nodulus - posture/balance/eyes |
|
|
Term
| Where are the inputs from in climbing fibers and mossy fibers of the cerebellum? |
|
Definition
| Climbing is from the inferior olive, mossy is from all inputs except the inferior olive |
|
|
Term
| What are the prinicipal inputs to the cerebellum? |
|
Definition
| The contralateral pons through the middle peduncle and ipsilateral inferior olive, vestibular nuc, and spinal chord through the inferior peduncle |
|
|
Term
| What are the principal ascending outputs from the cerebellum? |
|
Definition
| From the cortex the outputs go to the dentate nuc to the sup peduncle, to the contralateral side of VL thalamus, red nuc (goes to spinal cord), and sup colliculus |
|
|
Term
| What are the principal descending outputs from the cerebellum? |
|
Definition
| Cortex to deep fastigial nuc to inf peduncle to ipsilateral sup colliculus, reticular formation, and vestibular nuclei |
|
|
Term
| In the cortical cerebellar loop circuitry what is the function of the Purkinje neuron? |
|
Definition
| To inhibit the function of deep nuclei via GABA |
|
|
Term
| Describe the cerebellar loop circuitry. |
|
Definition
| Climbing and mossy glutamate fibers are part of the deep excitatory loop that drive both parallel fibers from granule cells and directly drive deep cerebellar nuclei; whereas the stim’d parallel fibers then stim Purkinje fibers which inhibit the deep nucs via the cortical inhibitory loop |
|
|
Term
| What type of diseases are Freidrich’s ataxia and Ataxia-telangiectasia? |
|
Definition
| Hereditary cerebellar ataxias that present in the first decade and they die in young adulthood |
|
|
Term
| When purkinje fibers normally fire they give simple spikes, but complex spikes increase during errors in new movement, how are these errors corrected when learning a new movement? |
|
Definition
| Complex spikes occur due to Climbing fibers increase there rate of firing on Purkinje fibers which reduces the strength of active parallel fiber inputs until error is fixed, so as the program is corrected for better movement the climbing fibers decrease their rate of firing. |
|
|
Term
| What is the difference between mossy and climbing fibers? |
|
Definition
| Climbing fibers are from the inferior olive indicating movement error and directly contact Purkinjes, Mossy fibers take sensorimotor context info from everywhere else and excite parallel fibers that stim purkinjes which inhibit deep nuclei |
|
|
Term
| How does long term depression of parallel fibers via climbing fibres work? |
|
Definition
| Thru protein kinase C pathway to reduce AMPA-glutamate receptors on purkinje cells at parallel fiber synapses that are active when climbing fibers fire. |
|
|
Term
| What is clarke’s nucleus? |
|
Definition
| A collection of cells in the thoracic segment of the dorsal spinal cord that relay proprioceptive information to the cerebellum. |
|
|
Term
| True or False: cerebellar cortex regulates motor functions on the ipsilateral side of the body. |
|
Definition
|
|
Term
| What part of the cerebellum are these clinical signs related to - equilibrium, balance, broad-based gait? |
|
Definition
| Vestibulocerebellum/flocculonodular node |
|
|
Term
| What part of the cerebellum are these clinical signs related to - postural instability, ataxia, primarily involving leg movements? |
|
Definition
| Midline vermis and intermediate zones (spinocerebellar) |
|
|
Term
| What part of the cerebellum are these clinical signs related to - intention tremor, ataxia, hypotonia? |
|
Definition
| Lateral hemisphere/cerebrocerebellum |
|
|
Term
| T or f: The MLF is related to eye muscle nuclei and vestibular nuclei. |
|
Definition
|
|
Term
| What is the main composition of myelin from oligodendrocytes which myelinate many axons in the CNS? |
|
Definition
| Lipid made largely of cerebroside |
|
|
Term
| What is significant about NG2+ oligodendrocyte cells? |
|
Definition
| They are precursor cells that allow for remyelination, they also fire AP and receive synapses from neurons |
|
|
Term
| Which of the follwing are important proteins in myelin in the CNS - cytoplasmic MBP, MAG, OMgp? |
|
Definition
|
|
Term
| Name this disease: dymelination in specific regions (occipital and temporal), x-linked, early death, accumulation of long chain fatty acids due to peroxisomal deficiency? |
|
Definition
| ALD, adreno-leukodystrophy |
|
|
Term
| Name this disease: many demyelinated spots, progressive, less frequency near equator, brain stem/optic nerve/cerebellum particularly affected, treatment slows progression? |
|
Definition
|
|
Term
| Which of the following are potential pathways to overcome the inhibition of myelin regrowth and axon regeneration - blocking Nogo/MAG, using olfactory ensheathing cells (stem-cell like), bypassing regeneration by plasticity of network? |
|
Definition
| All of them, plasticity refers to available room and necessary factors for growth. |
|
|
Term
| The myelin signal proteins NOGO, MAG, OMgp all signal axons through the Nogo-receptor which then inhibits what? |
|
Definition
|
|
Term
| True or False: The kinocilia are on the utricle side of the hair cells in the horizontal canal, but on the opposite side in the other 2 canals. |
|
Definition
|
|
Term
| T or F: The right vestibular nerve is excited during a horizontal rightward turn. |
|
Definition
|
|
Term
| T or F: The hair cells depolarize when the cupula is pushed in the direction of the kinocilia, opening tip-link K+ channels. |
|
Definition
| True, when the hairs move away from the kinocilia the K+ and Ca+ channels close hyperpolarizing the cell |
|
|
Term
| Endolymph is the vestibular ducts that has High K+ and low Na+, this fluid is made by what type of cells in the vestibular organs? |
|
Definition
|
|
Term
| The push-pull response describes the vestibular system, what is it? |
|
Definition
| It means that the bony labyrinths are mirror images of each other, so when angular rotation induces excitation in the left canal there is inhibition in the right canal; this gives a better way for the CNS to notice differences in firing rate between the two sides since vestibular nuclei project contra to opposite side nuclei |
|
|
Term
| What is the difference in types of movement measured between semicircular canals and otolith organs? |
|
Definition
| Angular versus linear acceleration |
|
|
Term
| How is the arrangement of hair cells in the otolith organs different from the semicircular organs? |
|
Definition
| The hairs of the otoloith organ don’t all line up the same way, but all facing the striola groove facing opposite directions; the utricle and saccule hairs register movement of the dense otoconia versus the endolymph like the semicircular canals |
|
|
Term
| Vestibular information goes from vestibular Scarpa’s ganglion to the vestibular nuclei and the cerebellum, describe what happens to the projections from the medial and lateral nuclei. |
|
Definition
| Medial nuclei goes to MLF as the medial vestibulospinal tract in the cervical spine to mediate head position, whereas the lateral nuclei go ipsi lateral vestibulospinal tract of spine to control balance and posture. |
|
|
Term
| To which of the following places does vestibular information go: lateral vestib nuc, medial vestib nuc, cerebellum, reticular formation, thalamus then parietal cortex, eye movement nuc (3,4,6), contra vestib nuc. |
|
Definition
|
|
Term
| What are saccadic eye movements? |
|
Definition
| Rapid movements 2-3 times per sec that brings objects into the fovea, ballistic (can’t be stopped), voluntary and automatic |
|
|
Term
| What are smooth eye pursuits? |
|
Definition
| Driven by visual input, keeps moving objects on fovea in a single direction, eyes move 60 ms after object begins to move, 100-200ms for the initial following response, and then 150-300 ms to create a saccade to will bring object onto fovea |
|
|
Term
| Vergence eye movements refer to what? |
|
Definition
| Eyes move in opposite directions to keep object at 50 cm or closer in focus, like magic eye or bring your finger close to your face. |
|
|
Term
| The vestibule-ocular reflex VOR keeps a stimulus on the fovea during head rotations, describe the synaptic chain of events if the head rotates left. |
|
Definition
| Head rotates left, endolymph goes right, cupula moves to utricle, signal goes to Scarpa’s ganglion, to vestibular nuclei, vestib nuc excites contra abducens nuc and inhibits ipsi abducens nuc, contra abducens pulls right LR muscle and stims CN3 to pull left MR muscle, while vestib nuc inhibs ipsi abducens nuc on opposite muscles. Opposite is true for right pathway, except that it provides weak signals so as not to interfere. |
|
|
Term
| T or F: CN III and VI innervate ipsi muscles and CN IV innerves contra muscles. |
|
Definition
|
|
Term
| The direction of nystagmus is defined by the fast phase, which is what? |
|
Definition
| The saccade direction towards the center, which is different from the slow phase which is the smooth tracking eye movement. |
|
|
Term
| What is optokinetic nystagmus? |
|
Definition
| When tracking a moving stimulus there is an intial ocular following response in the slow phase then a fast phase, OKN is very hard to inhibit with a big stim field |
|
|
Term
|
Definition
| Nystagmus occurs when you rotate your head opposite the direction you are looking, as in spinning, with the fast phase in the direction you turn. |
|
|
Term
| In caloric nystagmus there is a rule of thumb called COWS, what is it? |
|
Definition
| Cold water induces nystagmus in the opposite direction, warm=same; even though the circuit causes the eyes to drift in the opposite direction |
|
|
Term
| In pathological nystagmus which direction does fast phase occur? |
|
Definition
|
|
Term
| T or F: headaches can be stimulated in the absence of vasodilation by stimulating the periaqueductal region in the brainstem or insular cortex. |
|
Definition
|
|
Term
| What is the difference between primary and secondary headaches? |
|
Definition
| Primary is intrinsic to brain without underlying structural, infectious, or toxic/metabolic causes like migraine, cluster, tension, sex headaches; secondary has IDable cause like tumor, hemorrhage, meningitis, etc |
|
|
Term
| When investigating primary headaches what should you do if the brain scan MRI comes back negative? |
|
Definition
|
|
Term
| What type of headache has either an aura visual sensory initiation or has the following without aura - last 4 to 72 hours, nausea, photo/phonophobia, pulsating, mod to severe? |
|
Definition
|
|
Term
| Which of the following are common misdiagnoses that are actually migraines - TMJ, Tension/neck aches, sinus headache? |
|
Definition
|
|
Term
| T or F: diagnosis (self or physician) of migraine is almost always correct and diagnosis of non-migraine is almost always correct. |
|
Definition
| False, diagnosis of non-migraine is usually migraine; migraines have other features like characteristic triggers, perimenstrual timing, abatement with sleep |
|
|
Term
| What are common headache triggers? |
|
Definition
| Irregular meals, caffeine, chocolate, nuts, bananas, sleep; stress or let down from stress |
|
|
Term
| Which of the following medications may make headaches worse - OCP, hormone replacement, SSRI, tapering steroids, decongestant withdrawal, benzos? |
|
Definition
|
|
Term
| T or F: migraines predominate in women whereas clusters predominate in men. |
|
Definition
|
|
Term
| Which meds are good for acute headache therapy and which are good prophylaxis? |
|
Definition
| Triptans for acute; prophylaxis - beta blockers, tricyclics, NSAIDS, MAOi, 5HTreupi, topiramate |
|
|
Term
| What are the key features of cluster headaches? |
|
Definition
| Men, eye pain, clusters of episodes, unilateral tearing/runny nose, circadian pattern; treated with short course of steroids or triptans, or verapamil |
|
|
Term
| What type of drug doesn’t help tension headaches? |
|
Definition
|
|
Term
| What is this vestibular disorder - brief episodes of vertigo when head is moved in plane of canal, worse in recumbency, nystagmus consistent with affected side (usually torsional vertical,ie down), no hearing loss/neuro deficits, normal gait? |
|
Definition
| Benign paroxysmal positional vertigo, BPPV; where otoconia particles are trapped in posterior semicircular canals affecting ipsi superior oblique and contra inferior rectus. |
|
|
Term
| What are the Dix-Hallpike and canalith repositioning maneuver testing for? |
|
Definition
| Dix-Hallpike tries to induce nystagmus and vertigo to diagnose BPPV where symptoms occur on the malfunctioning side; repositioning maneuver requires the head to be rotated to the opposite side to reposition the crystals in the vestibular apparatus |
|
|
Term
| What is this vestibular disorder- vertigo and nausea for days, ho nearing loss, caloric paresis, week for ambulation, positive head impulse test (checks for cerebellar infarct which would make test negative), secondary to viral reactivation? |
|
Definition
| Vestibular neuritis, usually symptomatic treatment only for nausea |
|
|
Term
| What vestibular disorder is this - dilated endolymphatic space, episodes of vertigo and auditory symptoms, gradual loss of high freq hearing and vestibular function? |
|
Definition
| Endolymphatic Hydrops; medical treatment is diuretics, salt reduce, stress reduce, surgical can involve injections or labyrinthectomy. if losses aren't gradual then it isn't this disease. |
|
|
Term
| Which of the following 2 groups is peripheral or central nystagmus - 1. unidirectional, in plane with canal affected, inhibit with fixation(follow an image), fast compensation, normal ocular control and neuro exam; 2. direction changing, direction incompatible with any ear structure, no inhibition/compensation, ocular and neuro exam probs. |
|
Definition
|
|
Term
| T or F: myelin in MS is affected in both the CNS and PNS. |
|
Definition
| False, CNS only, PNS relatively intact |
|
|
Term
| MS affects adults in what age groups? |
|
Definition
|
|
Term
| MS has no specific diagnostic tests, since its defining feature is disseminated lesions in space and time, which of the following lab tests are helpful - CR, MRI, evoked potentials (visual, somatosensory, brainstem), or CSF fluid analysis (for IgG synthesis rate or oligoclonal bands)? |
|
Definition
|
|
Term
| What is the range for the extended disability status scale (EDSS) in MS? |
|
Definition
| 1 being normal exam to 10 being death due to MS, devised by assessment of functional systems |
|
|
Term
| List the following in most to least common displays of MS in patients - primary progressive, secondary progressive, primary relapsing, remitting-relapsing. |
|
Definition
| remitting-relapsing, secondary progressive, primary progressive, primary relapsing; most patients start with remitting then progress to secondary |
|
|
Term
| When looking at T-1 weighted MRI’s to detect MS and its affect on the BBB, what do the white spots on the image indicate? |
|
Definition
| BBB disruption indicates acute inflammatory activity within the CNS |
|
|
Term
| Most patients with MS have both acute and chronic demyelinating lesions, describe each one. |
|
Definition
| Acute - active inflammation around venules involving T-cells and phagocytosis of myelin by macrophages; Chronic - little inflammation, absence of myelin with relative preservation of axons, proliferation of astrocytes, axonal degeneration may occur |
|
|
Term
| Since MS demyelination plaques have a predilection for periventricular areas, describe the role of Na in the axon degeneration cascade. |
|
Definition
| Inflammation, hypoxia, or microglia cause mitochondria to stop producing ATP which stops Na/K pumps allowing Na to flood in and participate in the Na/Ca pump, excessive calcium causes activation of destructive enzymes |
|
|
Term
| With MS there is a genetic susceptibility associated with immune response genes, increased risk with 1st degree relatives and monozygotic twins but what is the environmental factor? |
|
Definition
| Occurs in temperate regions, not in equator; after age 15 if a person migrates to another region they keep the susceptibility from their region of origin; there are no consistently linked viral factors |
|
|
Term
| Information from mouse models induced experimental autoimmune encephalomyelitis has shown a correlation about T-cell Th1 and Th2 cytokines, what is it? |
|
Definition
| Th1 cytokines mediate much of CNS damage but Th2 is protective; during MS a patients immune system is shifted towards Th1 |
|
|
Term
| Which of the following MS drugs are for acute attacks and which are for prophylaxis - interferon b, copolymer 1, solu-medrol? |
|
Definition
| First two prophylaxis, last acute |
|
|
Term
| Name this disease: dysmyelinating disorder resulting from the breakdown of abnormal myelin, linked to abnormalities in myelin synthesis. |
|
Definition
|
|
Term
| Name this disease: caused by an opportunistic viral infection called papovavirus, that causes multifocal demyelination in immunosuppressed patients with brain cavitation. |
|
Definition
| Progressive multifocal leukoencephalopathy PML |
|
|
Term
| Name this disease: central region of demyelination of the pons resulting from rapid correction of severe hyponatremia, also occurring in liver patients. |
|
Definition
| Central pontine myelinolysis |
|
|
Term
| Name this disease: post-vaccination or viral syndrome characterized by widespread demyelination of microfoci accompanied by perivascular lymphocytic inflammation. |
|
Definition
| Acute disseminated encephalomyelitis, ADEM |
|
|
Term
| T or F: Pure cerebellar syndromes have normal muscle strength/sensation/deep tendon reflexes, mild decrease in tone, and no vertigo. |
|
Definition
|
|
Term
| What is dysdiadochokinesia, which is a sign of cerebellar dysfunction? |
|
Definition
| Inability to perform rapid alternating muscle movements, like rubbing a heel of one foot on opposite shin. |
|
|
Term
| ID whether the following 2 groups of signs and symptoms is either due to cerebellar or spinal long tract lesions - 1. possibly due to SCA2, dominant, 25-50 yr olds, global and progressive ataxia, reduced DTR’s and downgoing toes, axonal neuro, slowed saccades of EOMs, cerebellar and pontine atrophy; 2 - possibly Freidrich’s, no dom inheritance, 5-25 yrs, caudal to rostral progression, absent lower reflexes, upgoing toes, fixed EOM instability, Scoliosis, cervical cord atrophy. |
|
Definition
| 1 is cerebellar, 2 is spinal long tract |
|
|
Term
| T or F: neuronal activity increases myelination |
|
Definition
|
|
Term
| which of the following are reasons to do neuroimaging in the case of a headache - abnormal neuro, onset over 55, fever, sudden onset, refractory to treatment, first or worst ever |
|
Definition
|
|
Term
| T or F: perilymph is between the duct and bone of semicircular canals and has the same ionic concentrations as CSF. |
|
Definition
|
|
Term
| If the kinocilia is pointing towards the striola it is in the _________, but if it is projecting away from the line then it is in the ___________. |
|
Definition
|
|
Term
| T or F: The vestibular push pull mechanism also works with anterior and posterior canals on opposite sides. |
|
Definition
|
|
