Term
| What are the 3 main categories of movement disorders. |
|
Definition
hyperkinetic
bradykinetic
tremor |
|
|
Term
| What are the classic manifestations of Parkinson's |
|
Definition
Characterized by slowness of movement (bradykinesia), increased tone (rigidity), tremor (asymmetric, pill-rolling common), loss of postural reflexes
Walk: slow, hunched over, shuffled short steps, no arm swing, instability
Sometimes have trouble starting to walk, then shuffle forward quickly, almost falling down
Also common – decreased voice volume, decreased facial expression |
|
|
Term
| What drug is Parkinson's responsive to that no other akinetic-rigid movement disorders are? |
|
Definition
|
|
Term
| a heterogenous group of Akinetic-rigid syndromes which share some clinical features of idiopathic Parkinson’s Disease, but have atypical clinical features (little or no response to L-Dopa/dopamine agonists) |
|
Definition
|
|
Term
| Antibodies to glutamic acid decarboxylase (GAD), which converts glutamic acid to GABA – so this person does not have as much GABA in their gamma motor neuron as they should. Legs are stiff – person walks like Frankenstein |
|
Definition
|
|
Term
| How does Juvenile Huntington’s Disease present differently form Adult Huntington's disease? |
|
Definition
presents with rigidity (as opposed to adult, which presents with chorea and dementia)
(and, of course, presents younger) |
|
|
Term
problem with copper incorporation
Resting and postural tremor, possible intellectual problems
Treatable, but often missed diagnosis |
|
Definition
|
|
Term
reflexes work, but cannot voluntarily move face (motor nuclei are normal, but there is a disconnect in the brain)
Have difficulty with balance/posture – walk rigidly with their head up, if you push them, they will just fall over |
|
Definition
| Progressive supranuclear palsy |
|
|
Term
| person presents with dementia, psychosis, and Parkinsonism |
|
Definition
| Diffuse Lewy Body disease |
|
|
Term
| How does Diffuse Lewy Body disease present differently from Idiopathic Parkinsons? |
|
Definition
| Diffuse Lewy Body Disease also presents with dementia & psychosis, while Parkinson's is strictly a movement disorder |
|
|
Term
| An older patient presents with rigidity and dementia, Autonomic Nervous System (ANS) dysfunction, ataxia, cerebellar dysfunction, speech impairment |
|
Definition
|
|
Term
| Dementia, severe impairment of proprioception (alien limb syndrome), touch them and they will jerk (stimulus-sensitive myoclonus) – also have severe contractions in one hand, tremor in the other |
|
Definition
| Corticobasal ganglionic degeneration |
|
|
Term
| What are the characteristics of Vascular Parkinsonism? |
|
Definition
step-down progression
due to a series of small strokes that affect the basal ganglia
will also have evidence of strokes on MRI or CT |
|
|
Term
| Prescribed drugs to treat _________ may destroy the substantia nigra & induce Parkisonism. |
|
Definition
|
|
Term
| sudden, brief, stereotyped (always the same), repetitive, normally coordinated but inappropriate movements |
|
Definition
|
|
Term
| Can tics be depressed? What makes them worse? |
|
Definition
Can be suppressed for brief periods with voluntary effort, but only with a rising sense of urgency that is relieved by expression of the tic
Can become worse with emotional stimulation |
|
|
Term
| typically fluctuating but relatively fixed (even compared to athetosis) postures due to persistent and abnormal patterns of increased motor tone. May be isolated to a body part (focal), multiple parts in a region (segmental), or generalized |
|
Definition
Dystonia
Ex: writer’s cramp, spasmodic torticollis, and the severely abnormal posturing of spastic cerebral palsy |
|
|
Term
| brisk, rapid, unpredictable, unsustained, irregular, jerking movements with a distal predominance |
|
Definition
|
|
Term
| irregular, forceful, slow, writhing (snake-like) movements, predominately affecting the extremities |
|
Definition
|
|
Term
| violent, involuntary, swinging/flinging movements due to lesions of the subthalamic nucleus (typically due to stroke, in which they occur acutely but do not persist long-term) |
|
Definition
|
|
Term
| violent, involuntary, swinging/flinging movements due to lesions of the subthalamic nucleus (typically due to stroke, in which they occur acutely but do not persist long-term) |
|
Definition
|
|
Term
| Ballism is due to lesions of the ______ nucleus |
|
Definition
|
|
Term
| What can you tell someone with who has had a stroke & presents with ballism? |
|
Definition
| it will go away on its own |
|
|
Term
| involuntary patterned, repetitive, continuous, coordinated, purposeless or ritualistic movements, postures or utterances – may be difficult to distinguish from tics. Unlike tics, these usually begin before the age of three, involve more of the body, are more rhythmic and less random, and are associated more with engrossment in another activity rather than premonitory urges |
|
Definition
|
|
Term
| abnormal feeling of restlessness, irresistible urge to move |
|
Definition
|
|
Term
| abnormal excess involuntary movements – combined features of chorea and stereotypies (often drug or toxin-induced movement disorders with dysregulation of dopamine-modulated activities in the nigrostriatal system) |
|
Definition
|
|
Term
| Task-specific action tremor |
|
Definition
| tremor when doing something (hand shakes when write) |
|
|
Term
| Parkinson’s Disease, Parkinsonisms, and Wilson’s Disease present with ___________ tremor |
|
Definition
|
|
Term
| Abrupt, brief shock-like jerks/muscle contractions |
|
Definition
|
|
Term
| a group of nuclei at the base of the forebrain and in the midbrain |
|
Definition
Basal ganglia
(note: ganglia is a group of neurons in the spine or PNS; neucleus is a group of neurons in the grain, so it ought to be "basal nuclei", but the name is too old to change now) |
|
|
Term
| • responsible for action selection (that is, decision of which of several possible behaviors to execute at a given time) |
|
Definition
|
|
Term
| a brain structure consisting of a relatively compact cluster of neurons (gray matter) |
|
Definition
|
|
Term
| The striatum, pallidum, substantia nigra, & subthalamic nucleus are all part of the |
|
Definition
|
|
Term
| a group of nuclei including the caudate (“tail”) nucleus, , nucleus accumbens septi (“leaning against”), and lentiform (“shaped like a lens”) nucleus (which consists of the putamen (“shell”) and globus pallidus (“pale globe”)) |
|
Definition
|
|
Term
| consists of the putamen (“shell”) and globus pallidus (“pale globe”) |
|
Definition
|
|
Term
receives input from many brain areas
only sends output to other parts of basal ganglia |
|
Definition
|
|
Term
receives most of its input from the striatum (either directly or indirectly)
sends inhibitory output to a number of motor-related areas, inluding the part of the thalamus that projects to the motor-related areas of the cortex
Does NOT provides dopamine input to striatum |
|
Definition
Pallidum
(the substantia nigra functions the same way, but also provides dopamine input to striatum) |
|
|
Term
Part functions like the pallidum:
receives most of its input from the striatum (either directly or indirectly)
sends inhibitory output to a number of motor-related areas, inluding the part of the thalamus that projects to the motor-related areas of the cortex
Part provides dopamine input to striatum |
|
Definition
|
|
Term
| The substantia nigra provides dopamine input to the ___________ |
|
Definition
|
|
Term
Receives input mainly from striatum & cortex
Projects to the pallidum |
|
Definition
|
|
Term
| The caudate nucleus is lateral to & follows the course of the __________________ |
|
Definition
|
|
Term
|
Definition
|
|
Term
| Bridges between caudate and putamen pass through the _________________ |
|
Definition
|
|
Term
| Putamen + Globus Pallidus = |
|
Definition
|
|
Term
| Caudate nucleus + putamen of the lentiform nucleus + nucleus accumbens septi |
|
Definition
|
|
Term
| Caudate, putamen, Globus Pallidus, Substantia nigra, subthalamic nucleus, nucleus accumbens |
|
Definition
|
|
Term
|
Definition
Motor Loop—concerned with learned movements
Cognitive Loop—concerned with motor intentions
Limbic Loop—concerned with emotional aspects of movement
Oculomotor loop—concerned with voluntary saccades of eye movement |
|
|
Term
|
Definition
| a fast movement of an eye, head or other part of an animal's body or device (rather than tracking smoothly, voluntary eye movement typically consists of saccades, or jumps of focus) |
|
|
Term
| Parkinsons is due to degeneration of the ________________ of the substantia nigra |
|
Definition
|
|
Term
| In Parkinson's, a small # of ________________ accumulate in the pars compacta of the substantia nigra |
|
Definition
Lewy bodies
(far fewer than in Lewy Body Disease) |
|
|
Term
|
Definition
writing becomes small and decreases in size with continued writing
occurs in Parkinsons |
|
|
Term
| Why do people with Parkinson's have cogwheel rigidity? |
|
Definition
| people with Parkinsons have muscle rigidity, and also sub-clinical tremors that cause tiny clicking feelings when you passively move their limbs |
|
|
Term
| Arises from midbrain, passes into interpenduncular fossa, passes into superior orbital fissure, and separates into upper (superior) & lower (inferior) divisions |
|
Definition
|
|
Term
| Innervates the muscles that raise the gaze, turn the gaze medially, and turn the gaze out & up. |
|
Definition
|
|
Term
| What 3 nerves move the gaze? |
|
Definition
occulomotor CN III
trochlear nerve CN IV
abducens nerve CN VI |
|
|
Term
| What directions do the CN IV & CN VI move the gaze. |
|
Definition
CN IV, trochlear--moves gaze down
CN VI, abducens--moves gaze out
(so if there's a lesion in III, gaze is stuck down & out) |
|
|
Term
| What happens if the CN III is lost? |
|
Definition
CN III is the oculomotor nerve
Complete ptosis
Eye is stuck with gaze down & out
Pupil is dilated |
|
|
Term
| What cranial nerve moves the gaze down? |
|
Definition
|
|
Term
| Emerges from dorsal surface of midbrain, passes forwards beneath the tentorium cerebella, passes thru the cavernous sinus, and enters eye orbit thru superior orbital fissure. |
|
Definition
|
|
Term
| Diplopia (Double vision) when attempting to read or go down a staircase is a sign of a lesion in the _____________ cranial nerve |
|
Definition
CN IV; trochlear
(b/c the trochlear moves the gaze down; lesion to trochlear means one eye doesn't move down with the other) |
|
|
Term
| What is Bielchowsky sign, and what nerve damage might it indicate? |
|
Definition
when looking down, patient will tilt head toward unaffected sign in order to better line up fields of vision
symptomatic of CN IV (trochlear) lesion |
|
|
Term
| What is the jaw herk reflex and what does it indicate? |
|
Definition
the mandible—or lower jaw—is tapped at a downward angle just below the lips at the chin while the mouth is held slightly open. In response, the masseter muscles will jerk the mandible upwards.
Normally this reflex is absent or very slight. An UMN lesion in the trigeminal (CN V) tract will make it more pronounced. |
|
|
Term
| What cranial nerve innervates the muscles of mastication (the temporalis & masseter)? |
|
Definition
| CN V, trigeminal (specifically, the mandibular branch) |
|
|
Term
| What cranial nerve innervates the muscles of facial expression (ex., buccinators)? |
|
Definition
|
|
Term
Right cheek flattened b/c of atrophy of masseter
Jaw deviates to right on opening mouth
What cranial nerve has a lesion? |
|
Definition
|
|
Term
| What cranial nerve turns the gaze outward? |
|
Definition
|
|
Term
| If you have right abducens palsy, what can't you do? |
|
Definition
| turn the gaze of the right eye toward the right (abduct the right gaze) |
|
|
Term
| A person has left CN VI palsy. Their eyes look completely normal, except when the try to: |
|
Definition
|
|
Term
Innervates muscles of facial expression and buccinator— a thin quadrilateral muscle that holds the cheek close to the teeth while chewing.
Does not innervate the muscles of mastication. |
|
Definition
|
|
Term
| What are the 5 branches of the facial nerve, from top to bottom. |
|
Definition
temporal (to temple)
zygomatic (to cheek)
buccal (to mouth)
mandibular (to lower jaw)
cervical (to neck) |
|
|
Term
Explain the following mnemonic:
To Zanzibar By Motor Car |
|
Definition
This is for the 5 branches of the facial nerve:
Temporal
Zygomatic
Buccal
Mandibular
Cervical |
|
|
Term
| Explain what happens if you have an upper motor neuron lesion in the right facial nerve tract. |
|
Definition
hemiparesis of left lower face (b/c all lower facial nerves decussate); can't smile contralateral to lesion
no paresis of forehead & upper eyelid b/c redundant innervation from both sides (half decussate; half innervate ipsilateral forehead). |
|
|
Term
| LMN lesion of ALL facial nerves on one side of face. Can't smile or raise eyebrows ipsilateral to lesion. |
|
Definition
|
|
Term
| A person has complete paralysis of one side of the face. Is that an upper motor neuron lesion, or a lower motor neuron lesion. |
|
Definition
| LMN (b/c upper motor nerves have dual innervation of the forehead; specifically, it's Bell's palsy) |
|
|
Term
| Where does the facial nerve (CN VII) emerge from the brainstem? |
|
Definition
| between the pons & medulla |
|
|
Term
| This cranial nerve is mostly sensory, but also innervates one muscle on the side of the neck that faciliates swallowing. |
|
Definition
|
|
Term
| A lesion to what cranial nerve could cause tongue deviation ipsilateral to lesion with crevices from wasting? |
|
Definition
|
|
Term
| A person can't shrug their right shoulder and has some wasting. What cranial nerve could be damaged? |
|
Definition
| CN XI, accessory (innervates trapezius & sternocleidomastoid) |
|
|
Term
| Where does the vagus nerves (CN X) provide sensory and motor innervation? |
|
Definition
|
|
Term
| What 2 criteria must be fulfilled in order to fit Tourette's? |
|
Definition
The following must have been present at some time (though not necessarily concurrently)
Multiple motor tics
And At least one vocal tic |
|
|
Term
| >60% of people tourette's have co-morbid ___________, while about 50% have co-morbid ____________ |
|
Definition
|
|
Term
| Do tics typically increase or decrease when engaging in activity that requires attention |
|
Definition
|
|
Term
| The median onset age of tourette's is _______, and it always onsets ______? |
|
Definition
|
|
Term
| What is the temporal pattern of tics over a day? |
|
Definition
| ics come in bouts, separated by non-tic periods of seconds to hours |
|
|
Term
| What is the most common first tic in tourette's and other tic disorders? |
|
Definition
|
|
Term
| A child develops motor tics. If the child has tourette's, when will he or she most likely develop vocal tics? |
|
Definition
| 1-2 years after developing motor tics |
|
|
Term
| What happens to tourette's in adulthood? |
|
Definition
usually tics diminish in adulthood (may disappear completely or just be less severe)
Rarely, can worsen during adult life. Extreme Tourette’s in adulthood is very rare |
|
|
Term
| What percent of schoolchildren have some kind of tic disorder? |
|
Definition
|
|
Term
usually simpler than tourette’s
Single or multiple motor tics or vocal tics, but not both
Typically lasts 4 weeks-1 year (never >1 year) |
|
Definition
|
|
Term
| What is the most common type of tic disorder? |
|
Definition
|
|
Term
| How long must a tic disorder last to be classified as Tourette's |
|
Definition
The tics occur many times a day (usually in bouts) nearly every day or intermittently throughout a period of >1 year
During these period, there was never a tic-free period of >3 consecutive months |
|
|
Term
| What is the difference between a compulsion & a tic. |
|
Definition
Different motivation:
Compulsions tend to be performed in reponse to obsession (ex., washing hands b/c of obsession with germs) as a result of a psychological urge.
Tics are preceded by a physical tension in the muscles that is reduced by the tics.
Also, compulsions are typically more elaborate & resemble more normal behaviors |
|
|
Term
Drug-induced disorder that typically involves movement of lips, mouth, & tongue.
Will improve when drugs are stopped (may also be given a dopamine agonist like levodopa) |
|
Definition
Tardive's dyskinesia
(
(Some neuroepileptic drugs used to treate Tourette’s can cause Tardive dyskinesia) |
|
|
Term
Uncontrollable urge to move legs & body (usually most affects legs & arms)
Unlike Tourettes, involves strange sensations deep within the muscle (pins & needles, tingling, numbness, itching, pain)
Normally affects older people (~60)
Urge to move is much worse in evenings |
|
Definition
|
|
Term
| How is Hunntington's chorea different than Tourette's |
|
Definition
Chorea (more dance-like than Tourette’s tics)
Symptoms manifest in older people(onset 20-50) |
|
|
Term
| What is a pronation/supination movement of the hand at 3-5 Hz called? |
|
Definition
|
|
Term
| At what age does Parkinson's typically present? |
|
Definition
|
|
Term
| Does idiopathic Parkinson's cause dementia? |
|
Definition
|
|
Term
| What skin condition is idiopathic Parkinson's associated with? |
|
Definition
| seborrheic dermatitis of on the face |
|
|
Term
| When someone first comes to you with symptoms of Parkinson's, what treatment do you give them? |
|
Definition
| First, just send to physical therapy & tell them to plan to retire early & buy a single-story house |
|
|
Term
| You don't want to give L-dopa (levodopa) for early Parkinson's because: |
|
Definition
| it can cause hyperkinetic movement |
|
|
Term
| For advanced Parkinson's, you give ________, which becomes ____________ in the brain. |
|
Definition
L-dopa (levodopa)
dopamine |
|
|
Term
| If idiopathic Parkinson doesn't respond to L-dopa, what can you do? What other kinds of Parkinsonism respond to this other treatment? |
|
Definition
deep brain stimulation
none; only idiopathic Parkinson's responds |
|
|
Term
Suprabulbar palsy—eyes won’t look up
Problems with balance
Stiff posture
Problem with autonomic system |
|
Definition
| Progressive Supranuclear Palsy |
|
|
Term
Large # of Lewy Bodies
hallucinations, psychosis
Stooped, shuffling |
|
Definition
| Diffuse Lewy Body Disease |
|
|
Term
Rigid
Old (typically 70s or 80s)
When they stand up, BP falls to 90
Atrophic cerebellum
No tremor
Don’t respond to L-dopa |
|
Definition
|
|
Term
Rare
Most noticeable symptom: Severe contractions in one hand & tremor in the other
Use a wheelchair
Demented
Severe impairment of proprioception (“alien limb syndrome”)
When you touch them, they jerk |
|
Definition
| Corticobasal Ganglionic Degeneration |
|
|
Term
| only kind of Parkinsonism w/ +Babinski |
|
Definition
| Vascular Parkinsonism (due to small strokes that affect connections between basal ganglia) |
|
|
Term
| palsy due to lesion above the brain stem |
|
Definition
|
|
Term
| Is the Parkinson's pill-rolling tremor symmetrical or asymmetrical? |
|
Definition
early on, it will be asymmetrical
later, it will become symmetrical |
|
|
Term
| Where is the lesion that causes ballism? |
|
Definition
|
|
Term
|
Definition
Tremor with no other problems.
(but may not actually be benign; can be completely disabling for some types of careers) |
|
|
Term
| What brain disorder is myoclonus often associated with? |
|
Definition
| epilepsy (as part of seizure) |
|
|
Term
| If a person has Wilson's disease, will the serum level of copper be low, normal, or high? What about the urine level of copper? |
|
Definition
|
|
Term
impairment of incorporation of copper into plasma
so, copper is deposited all over the place (including in the brain)
causes all kinds of hyperkinetic movement, esp. resting tremor, chorea, athetosis, ballism, dystonia, tic, and myoclonus |
|
Definition
|
|
Term
disease characterized by rapid, uncoordinated jerking movements affecting primarily the face, feet and hands.
Associated with childhood infection with Group A strep |
|
Definition
| Sydenham's chorea, aka Saint Vitus's Dance |
|
|
Term
| When used to apply genetic disorders, anticipation means |
|
Definition
| tend to get worse with every generation (describes trinucleotide repeat disorders) |
|
|
Term
|
Definition
| a trinucleotide expansion beyond normal, but not expanded enough to cause disease; can relatively easily cross the threshold in following generations into full mutation |
|
|
Term
What kind of genetic disorder does the following process create?
DNA polymerase “slips” when copying trinucleotide repeat & creates a hairpin of too many repeats on daughter strand
When daughter strand is copied, the result is DNA with too many repeats |
|
Definition
| trinucleotide expansion disorder |
|
|
Term
| most common known single gene cause of autism |
|
Definition
|
|
Term
| Is Fragile X dominant, recessive, or other? |
|
Definition
It’s somewhere between recessive & incompletely dominant
Males are predominantly affected
Females with 1 fragile X will have some signs of fragile X (ex., long face, excessive shyness) , but may or may not be considered to have the disease |
|
|
Term
| a disorder in which the X chromosome has a slender, de-condensed site |
|
Definition
|
|
Term
| >200 CGG repeats in the 5’UnTranslated Region (UTR) of the gene for Fragile Mental Retardation Protein (FMRP) affects methylation of the protein and causes loss of protein function |
|
Definition
|
|
Term
| Why is Fragile X always inherited from the mother? |
|
Definition
pre-mutations expand (possibly to full mutations) during female meiosis
full mutation decreases to pre-mutation during male meiosis (so a father with Fragile X will have daughters with pre-mutations) |
|
|
Term
Mental disability
speech delay
shy; trouble with eye contact
sensory integration problems; sensory defensiveness
Prominent ears (one or both)
Long face
High-arched palate (related to the above)
Hyperextensible finger joints
Double-jointed thumbs
Flat feet
Soft skin
Larger testes in men (macroorchidism)
Low muscle tone (May frequently need to take small breaks or lean their head on a table) |
|
Definition
|
|
Term
Autosomal Dominant Inheritance
RNA-mediated gain of function
a tri- or tetra-nucleotide repeat expansion disorder
Most common form of adult muscular dystrophy (although one form of this disorder appears in children)
Multisystem disorder
muscle weakness
cardiomyopathy
conduction defects
insulin resistance
balding
testicular atrophy
cataracts |
|
Definition
|
|
Term
| What determines the age of onset of Huntington's disorder? |
|
Definition
| the number of repeats--more repeats means earlier onset |
|
|
Term
Autosomal Dominant trinucleotide expansion disorder causes toxic gain of function
a neurological disorder marked by incessant, uncontrollable muscle twiches (aka St. Vitus’s dance).
Very rare in Africa; much more common in Venezuela
Atrophy of
caudate nucleus
putamen (to a lesser extent)
changes to other parts of brain (such as cortex) as disease progresses |
|
Definition
|
|
Term
Most common hereditary ataxia
Autosomal Recessive
Appears at age 5-15
Ataxia
Will eventually require a wheelchair, & die early
Tremor
Nystagmus
Scanning speech—speech in which syllables are separated by noticeable pauses
Kyphoscoliosis
Heart enlargement, arrhythmias, & heart failure
Frequently combined with chronic myocarditis |
|
Definition
|
|
Term
|
Definition
| speech in which syllables are separated by noticeable pauses |
|
|
Term
| the pathway that connects the substantia nigra to the striatum (dopamine is the neurotransmitter) |
|
Definition
|
|
Term
| The Nigrostriatal pathway is part of the basal ganglia ___________ loop |
|
Definition
|
|
Term
| refers to the CNS structural pathway that indirectly modifies movement (ex., walking, posture, fine motor control) without directly innervating motor neuron |
|
Definition
Extrapyramidal
motor cortex & pyramidal tracts (corticospinal & some corticobulbar) are involved in pathways that directly innervate motor neurons |
|
|
Term
| Bradykinesia, chorea, athetosis, ballism, dystonia, myoclonus, tremor, tics, & stereotypies are all symtpoms of _____________ lesions |
|
Definition
|
|
Term
Which of the following is more likely to switch from side to side? Which is more likely to affect one side exclusively?
chorea
athetosis |
|
Definition
chorea--switch from side to side
athetosis--one or both sides, but doesn't usually switch |
|
|
Term
| a neurological movement disorder in which sustained muscle contractions cause twisting and repetitive movements or abnormal postures |
|
Definition
|
|
Term
| involuntary, somewhat rhythmic, muscle contractions and relaxations involving to-and-fro movements (oscillations or twitching) of one or more body parts. |
|
Definition
|
|
Term
| Dopamine is an ____________ (inhibitory/ excitatory) neurotransmitter at most receptor subtypes |
|
Definition
|
|
Term
Explain the following mnemonic:
Dopamine says “Go”, while Acetylcholine says “Whoa” |
|
Definition
In the extrapyramidal motor system dopamine inhibits an inhibitory nerve in order to allow motor activity
Acetylcholine activates the inhibitory nerve via muscarinic receptors to slow motor activity |
|
|
Term
Explain what's wrong with the following statement.
Dopamine is mostly an inhibitory neurotransmitter, while acetylcholine is often excitatory, so dopamine in the brain inhibits movement while acetylcholine allows movement. |
|
Definition
| In the extrapyramidal motor system dopamine inhibits an inhibitory nerve in order to allow motor activity. Acetylcholine activates the inhibitory nerve via muscarinic receptors to slow motor activity. |
|
|
Term
| Too many CGG repeats in the untranslated 5' end of a chromosome cause: |
|
Definition
|
|
Term
| Too many CTG repeats in the untranslated 3' end of a chromosome cause: |
|
Definition
|
|
Term
| Too many GAA repeats in an intron cause: |
|
Definition
|
|
Term
| Too many CAG repeats in an exon cause: |
|
Definition
|
|
Term
| Why would you give a muscarinic antagonist, such as atropine, to someone with Parkinson's. |
|
Definition
Need dopamine to inhibit an inhibitory neuron. Acetylcholine excites the inhibitory neuron at muscarinic receptors. Antagonists at muscarinic receptors for acetylcholine compensate for dopamine deficiency
(But it's not used any more b/c it has too many side effects) |
|
|
Term
| The _________________ is necessary b/c a lot of substances whose levels fluctuate in blood are neurotransmitters in the brain brain (unlike the PNS, which only uses acetylcholine & noradrenaline/norepinephrine) |
|
Definition
|
|
Term
| Why would you give L-dopa with carbidopa to treat Parkinson's, rather than plain dopamine? |
|
Definition
If you just give dopamine, it will have systemic effects (lots of side effects).
Carbidopa prevents L-dopa from converting to dopamine.
L-dopa can cross the blood-brain barrier, while carbidopa can’t, so L-dopa only becomes dopamine in the brian. |
|
|
Term
| What undesirable effects can dopamine cause in the brain? |
|
Definition
Triggers vomiting in chemotactic trigger zone in the medulla
Too much in limbic system & frontal cortex can cause Psychosis
In the hypothalamus it inhibits pituitary release of prolactin, and has a role in temperature regulation |
|
|
Term
| Drug-induced Parkinsonism can be a side-effect of dopamine antagonists, which are used to treat ___________ & _________ |
|
Definition
|
|
Term
| What are the 3 categories of symmetric broad-based gait that we learned? |
|
Definition
sensory ataxia
loss of coordination
waddling (dystrophic) gait (that is, limb-girdle weakness) |
|
|
Term
| What are the 3 categories of broad based gait due to sensory ataxia that we learned? |
|
Definition
posterior/dorsal column disease (ex., tabes dorsalis or vitamin B12 deficiency)
peripheral neuropathy
multi-sensory dizziness |
|
|
Term
| A “waddling” gait can result from bilateral weakness of the ______ muscles (hip abductors) that power the pelvic tilt required for clearance of the foot during efficient walking. |
|
Definition
|
|
Term
| Why would people who have multiple sensory deficits (cataracts, hearing deficits, severe spondylosis, peripheral neuropathy, proprioception impairment) have a broad-based gait? |
|
Definition
input is disorganized--leads to dizziness and feelings of unsteadiness
(usually occurs in the elderly) |
|
|
Term
| What are the 3 causes of loss of coordination associated with broad-based gait that we learned? |
|
Definition
cerebellar ataxia
extrapyramidal disorders (chorea or dystonia) affecting gait
malingering or factitious incoordination |
|
|
Term
| If a person has symmetric broad-based gait as a result of loss of coordination due to cerebellar ataxia, what is the next question to ask? |
|
Definition
| is the cerebellar lesion midline or lateral |
|
|
Term
|
Definition
| inability to smoothly track and touch or manipulate a target with a limb – see “finger-to-nose” and “heel-to-shin” tests |
|
|
Term
|
Definition
| impaired rapid alternating movements – such as rapid alternating pronation and supination of the hands |
|
|
Term
|
Definition
| exaggerated and undampened rebound motion when a limb is abruptly released from active resistance |
|
|
Term
| Is Parkinson's gait broad-based, narrow-based, or normal-based? |
|
Definition
|
|
Term
| What is the posture like in Stiff-person syndrome? |
|
Definition
|
|
Term
| What lab test should you do if you suspect stiff-person syndrome? |
|
Definition
| check for anti-GAD antibodies |
|
|
Term
|
Definition
| difficulty initiating movement, hesitant, effortful and deliberate – with a loss of automaticity and with apparent ineffectiveness |
|
|
Term
| Peroneal nerve palsy and lumbar neuropathy can both cause foot drop. How can you distinguish between them using sensory symptoms? |
|
Definition
Peroneal nerve palsy is painless
Lumbar neuropathy causes severe radiating pain down back leg |
|
|
Term
| What part of the cerebellum is responsible for axial control, vestibular reflexes, & keeping head & neck properly oriented |
|
Definition
| vestibulocerebellum (archicerebellum) |
|
|
Term
| What part of the crebellum is responsible for motor control of trunk & proximal limbs, regulation of ongoing execution in trunk & proximal limbs, & regulates balance (keeps body erect) |
|
Definition
| medial spinocrebellum (aka medial paleocerebellum) |
|
|
Term
| What part of the cerebellum is responsible for distal motor control & regulation of ongoing execution of movement in distal limbs |
|
Definition
| lateral spinocerebellum (lateral paleocerbellum) |
|
|
Term
| What part of the cerebellum is responsible for motor learning, initiation, planning, execution, and cognitive tasks like timing & rhythm |
|
Definition
| crebrocerebellum (aka neocrebellum) |
|
|
Term
| What problems does a lesion to the medial spinocerebellum (medial paleocerebellum) cause? |
|
Definition
ataxic gait
dizziness that does not improve upon lying down
titubation--truncal tremors
truncal ataxia |
|
|
Term
| ethanol consumption causes a temporary interference (or permanent for alcohol posoining) in what part of the cerebellum? |
|
Definition
| medial spinocerebellum (aka medial paleocerebellum) |
|
|
Term
| What problems does a lesion of the lateral spinocerebellum (lateral paleocerebellum) cause? |
|
Definition
action tremors
ataxia of limb movements |
|
|
Term
| What problems does a lesion of the cerebrocerebellum (aka neocerebellum) cause? |
|
Definition
dysdiadokinesia (can't perform rapidly alternating movements)
dysmetria (overshoot or undershoot of arm/leg movement)
decomposition of movement (a distortion in voluntary movement in which motion occurs in a distinct sequence of isolated steps rather than in a normal smooth, flowing pattern) |
|
|
Term
|
Definition
| truncal ataxia—cannot maintain head in steady position, so it bobs back & forth |
|
|
Term
| The cerebellum is dorsal (posterior) to the _______ and _________, in the posterior cranial fossa |
|
Definition
|
|
Term
| Where does the vestibular cerebellum receive inputs from, and where does it send outputs to? |
|
Definition
inputs: vestibular labyrinth
outputs: axial motor neurons that control eyes
vestibulospinal tract-->adjust postural muscles to keep upright |
|
|
Term
| Where does the medial spinocerebellum (medial paleocerebellum) receive inputs from, and where does it send outputs to? |
|
Definition
inputs: vestibular labyrinth, proximal body parts, facial, visual & auditory inputs
outputs: vestbular nucleus, reticular formation (reticulospinal tract), motor cortex |
|
|
Term
| Where does the lateral spinocerebellum (lateral paleocerebellum) receive inputs from, and where does it send outputs to? |
|
Definition
inputs: spinal afferents (distal muscles of limbs)
outputs: red nucleus (rubrospinal tract), motor cortex for distal limb muscles (via thalamus) |
|
|
Term
| Where does the cerebrocerebellum (neocerebellum) receive inputs from, and where does it send outputs to? |
|
Definition
inputs: from pre-motor cortex
outputs: red nucleus, thalamus, pre-motor cortex |
|
|
Term
| connects the 2 hemispheres of the cerebellum |
|
Definition
|
|
Term
| most cerebellar lesions cause ___________ (ipsilateral/contralateral) deficits, but an exception is _________________ |
|
Definition
ipsilateral
Benedikt's syndrome |
|
|
Term
| receives input from vestibular nucleus, interprets, & sends signals to control eye movements & adjust postural muscles to keep upright |
|
Definition
|
|
Term
| The lateral medullary syndrome of Wallenberg is caused by a stroke of the ____________________________ artery |
|
Definition
| Posterior Inferior Cerebellar Artery (PICA) |
|
|
Term
| A lateral medullary syndrome of Wallenberg (stroke of Posterior Inferior Cerebellar Artery (PICA)), any associated cerebellar deficits are _____________ (ipsilateral/contralateral) to lesions |
|
Definition
| ipsilateral (most of cerebellar tracts don't decussate, so, except for Benedikt's syndrome, all cerebellar lesions cause ipsilateral deficits) |
|
|
Term
| Where do most cerebellar tracts decussate? |
|
Definition
most do NOT decussate
(so all cerebellar lesions cause ipsilateral deficits except for Benedikt's syndrome) |
|
|
Term
| If a patient enters the emergency room vomiting, why do you need to make them walk? |
|
Definition
| to cehck for unilateral cerebellar ataxia, which could indicate a serious brain lesion |
|
|
Term
Most common hereditary ataxia
autosomal recessive
involves the long tracts:
o Dorsal columns bilateral loss of fine touch, conscious proprioception, vibratory sense
Spinocrebellar tracts: bilateral cerebellar ataxia
Corticospinal tracts
Dentate nuclei
Frequently combined with chronic myocarditis
Signs & Symptoms
Appears at age 5-15
Ataxia
Will eventually require a wheelchair, & die early
Tremor
Nystagmus
Scanning speech—speech in which syllables are separated by noticeable pauses
Kyphoscoliosis
Heart enlargement, arrhythmias, & heart failure |
|
Definition
|
|
Term
| Subacute combined degneration (aka untreated pernicious anemia) is caused by |
|
Definition
| a deficiency of vitamin B12 (cyanocobalamin) |
|
|
Term
| B12 deficiency causes a loss of what 3 tracts? |
|
Definition
Dorsal columns --> bilateral loss of fine touch, conscious proprioception, vibratory sense
Lateral white columns --> bilateral upper motor neuron spastic paralysis
Dorsal spinocerebellar tract --> bilateral cerebellar ataxia |
|
|
Term
bilateral loss of fine touch, conscious proprioception, vibratory sense
bilateral upper motor neuron spastic paralysis
bilateral cerebellar ataxia
positive Romberg sign—can stay upright with eyes open, but sway or fall with eyes closed
sensory ataxia of gait—“stamp & stick” gait (as in tabes dorsalis)
due to loss of dorsal column
revealed when patient tries to walk in tandem (heel to toe)
patient can’t feel position of foot relative to ground, so they stamp
watch feet as they walk
also, need a stick (cane) to keep their balance |
|
Definition
| vitamin B12 deficiency (aka subacute combined degeneration or untreated pernicious anemia) |
|
|
Term
| Pernicious anemia causes difficulty in absorbing ____________ |
|
Definition
|
|
Term
Cerebellar ataxia
Ataxia of the lower limb
Ataxia of the truncal musculature
Poor results on heel-to-shin test
Pendular reflexes
Poor results on tandem walking test
Negative Romberg sign
Often associated with chronic alcoholism |
|
Definition
| anterior vermis syndrome (atrophy of rostral/anterior vermis in spinocerebellum, commonly due to chronic alcholism) |
|
|
Term
|
Definition
| wide-based, unstable and staggering gait |
|
|
Term
| 3 kinds of appendicular ataxia (that is, ataxia of the distal limbs) |
|
Definition
Dysmetria—a type of lack of coordination typified by the undershoot or overshoot of intended position with the hand, arm, leg, or eye Problems with nose-finger test & heel-to-shin test
Dysdiadochokinesis— inability to perform rapid, alternating movements
Dysrhythmia—problems with rhythm |
|
|
Term
|
Definition
|
|
Term
|
Definition
| a kind of trunk tremor that results in head bobbing (causes staggering or reeling) |
|
|
Term
|
Definition
| involuntary eye movement (esp. rhythmic, oscillating movements) |
|
|
Term
|
Definition
| nystagmus in which the eyes move simultaneously in the same direction |
|
|
Term
|
Definition
nystagmus in which the eyes do not move simultaneously in the same direction
Ex., slowing of the adducting eye and overshoots of the abducting eye, or “see sawing” of eyes (one up, one down) |
|
|
Term
| Gaze paresis (gaze paretic nystagmus |
|
Definition
| a conjugate nystagmus due to cerebral or pontine lesion, in which gaze tends to deviate in one direction (typically the direction of the lesion) |
|
|
Term
The patient cannot voluntarily look to the right and the eyes spontaneously deviate to the left. The patient may be able to return the gaze voluntarily to the midline but cannot move the eyes past the midline into the paretic field of gaze.
Where is the lesion most likely? |
|
Definition
right cerebrum or pons
(gaze paresis is usually caused by cerebral or pontine lesion ipsilateral to the paretic field) |
|
|
Term
|
Definition
| a rare kind of gaze paresis in which the direction of deviation switches every few minutes |
|
|
Term
|
Definition
| loud, sudden speech uttered with more force than normal |
|
|
Term
|
Definition
| when the reflex is activated with a reflex hammer, rather than jerking once & stopping, the hanging part continues to swing for a few beats before stopping |
|
|
Term
| Where do midline (vermal) cerebellar syndromes cause problems? |
|
Definition
| typically near midline of body (ex., in trunk or head) |
|
|
Term
| Where do lateral cerebellar syndromes cause problems? |
|
Definition
|
|
Term
| a highly malignant primary brain tumor that originates in the cerebellum or posterior fossa. |
|
Definition
|
|
Term
| Chronic alcoholism is associated mainly with atrophy of the ____________ |
|
Definition
| vermis (midline of the cerebellum), esp. in the spinocerebellum |
|
|
Term
| In lateral (hemispheric) cerebellar syndromes, the deficit is typically ____________ (ipsilateral/ contralateral) to the lesion |
|
Definition
|
|
Term
| A rare type of posterior circulation stroke of the red nucleus, with a range of neurological symptoms affecting the midbrain, cerebellum (b/c tracts from the cerebellum run thru the red nucleus to the cerebral cortex) and other related structures. |
|
Definition
|
|
Term
| Cerebellar tracts decussate on the way to the red nucleus (which they pass thru on their way to the cerebral cortex). What does this mean for Benedikt's syndrome? |
|
Definition
Benedikt's syndrome (a stroke of the red nucleus in the midbrain) causes intention tremor contralateral to the lesion
This is the only syndrome that causes cerebellar symtpoms contralateral to the lesion (b/c cerebellar tracts descending to the body do NOT decussate) |
|
|
Term
| Benedikt's syndrome causes ___________ tremor contralateral to the lesion |
|
Definition
|
|
Term
|
Definition
| inability to flex the head forward due to rigidity of the neck muscles; often seen with meningitis |
|
|
Term
| You flex a child's hip to 90o, and they cry when you try to straighten the knee beyond 135o. What is this sign, and what could it indicate? |
|
Definition
|
|
Term
| While a child is lying on his back, you lift his head & his knees lift up. What is this sign, and what could it indicate? |
|
Definition
Brudzinski’s sign
could indicate meningitis |
|
|
Term
| If you suspect an intracranial bleed, should you request a CT with or without contrast? |
|
Definition
|
|
Term
Weight gain
cold intolerance
fatigue
somnolence
carpal tunnel syndrome
dry skin/hair
irregular menses
Recurrent acute headache that is increasingly severe and persistent |
|
Definition
|
|
Term
Scalp tenderness
Jaw claudication (aching, tired feeling)
Recurrent acute headache that is increasingly severe and persistent
Visual disturbances (often asymmetric) |
|
Definition
| cranial arteritis (also known as temporal arteritis or giant cell arteritis) |
|
|
Term
|
Definition
| painful, aching, cramping, uncomfortable, or tired feeling that is relieved by rest |
|
|
Term
| Cranial arteritis is a medical emergency because it could cause _______ or _______ |
|
Definition
|
|
Term
|
Definition
| (aka idiopathic intracranial hypertension, IIH)—increased intracranial pressure without tumor (it’s idiopathic—no one knows why- it happens) |
|
|
Term
| A young obese female with menstrual irregularity complains of persistent fluctuating headache, dramatically exacerbated by coughing, sudden movements, or change in position (reclining, standing, bending over) that often awakens her from sleep in the early morning hours. Occasionally, she has transient blurring of her vision or double vision. She has papilledema and can't look to the right with her right eye (CN VI palsy). |
|
Definition
| pseudotumor cerebri (aka idiopathic intracranial hypertension, IIH) |
|
|
Term
| Patients older than age 50 who experience the new onset of headache require special consideration because they are at greater risk for what 3 conditions? |
|
Definition
tumors
cranial/giant cell arteritis
intracranial bleeding (stroke) |
|
|
Term
| Where does the pain from a migraine typically occur? |
|
Definition
| usually occur on one side (though they may spread as the attack continues, attacks may not always occur on the same side). |
|
|
Term
Headache that is
Bilateral in distribution
Pressing or tightening (non-pulsating) in character
Mild to moderate in intensity
Not markedly aggravated by routine physical activity (like walking)
Not associated with significant nausea, phonophobia or photophobia
Not attributable to another disorder |
|
Definition
|
|
Term
a distinctive craniofacial pain syndrome of severe paroxysmal unilateral pain
Recurrences typically continue to affect the same side
Attacks tend to be relatively brief (spontaneously resolving within 15 minutes – 3 hours)
Attacks tend to occur in a vaguely periodic manner or in discrete clusters of recurring pain attacks
During the attack the patient is typically restless and/or agitated
During attack, may have conjunctival redness, nasal congestion or rhinorrhea, eyelid edema, forehead and facial sweating, miosis (constriction of pupil), or ptosis ipsilateral to pain
Attack may be precipiated by alcohol consumption, smoking or sleeping |
|
Definition
|
|
Term
| The trigeminal nerve exits the brainstem from the __________ |
|
Definition
|
|
Term
| trigeminal nerve ganglion |
|
Definition
| Trigeminal semilunar (or gasserian) ganglion |
|
|
Term
| 3 divisions of the trigeminal nerve |
|
Definition
Opthalmic Nerve (CN V-1)
Maxillary Nerve (CN V-2)
Mandibular nerve (CN V-3) |
|
|
Term
| What component of the trigeminal nerve innervates the muscles of mastication (temporalis, masseter, lateral & medial pterygoids)? |
|
Definition
| Mandibular nerve (CN V-3) |
|
|
Term
| The cerebral aqueduct is aka the ____________________ |
|
Definition
|
|
Term
| One of the most common causes of hydrocephalus is blockage of: |
|
Definition
| the cerebral aqueduct (aka the aqueduct of Sylvius) |
|
|
Term
| a physical manifestation of disease which originates in the mind rather than the body. Truly believe they are ill. Typically have multiple physical complaints over years. More common in women |
|
Definition
|
|
Term
|
Definition
| physical symptoms that originate from physical problems |
|
|
Term
| Secondary somatic symptoms |
|
Definition
physical symptoms that are secondary to psychological problems
Successful treatment of the psychological problem often causes the somatic symptoms to go away |
|
|
Term
| Condition in which a person acts as if he or she has an illness by deliberately producing, feigning, or exaggerating symptoms in order to gain the benefits of a sick role (attention, nurturance, sympathy, and leniency). May deliberately cause illness to themselves. They know that they're faking illness, but typically do not consciously understand why they need to do this |
|
Definition
| factitious disorders (older name: Munchausen’s disorder) |
|
|
Term
| fabricating or exaggerating the symptoms of mental or physical disorders for a variety of "secondary gain" motives, which may include financial compensation (often tied to fraud); avoiding school, work or military service; obtaining drugs; getting lighter criminal sentences. Health complaints cease when desired gain is achieved |
|
Definition
|
|
Term
| physical illnesses which have a psychological component (ex., stress exacerbates congestive heart failure) |
|
Definition
|
|
Term
the patient's consciously appreciated sensation of a physical problem
“I am manly-man and my head does not hurt!”
"This paper cut hurts a lot!!!" |
|
Definition
|
|
Term
| What do you need for normal symptom perception? |
|
Definition
normal symptom perception requires normal neural pathways for transmission & processing
conscious acknowledgement by the patient |
|
|
Term
recognition of what a symptoms means; assessment and interpretation of sensations are influenced by experience, learning, gender, culture, and beliefs
“Oh, sure, I have crushing chest pains, sudden onset of malaise & fatigue, and profuse sweating, but it’s probably indigestion.” |
|
Definition
|
|
Term
| What is the big difference between somatoform and factitious disorders? |
|
Definition
| people with somatoform disorders truly believe that they are sick |
|
|
Term
| conversion of psychological pain into body (“soma”) symptoms. |
|
Definition
|
|
Term
| the preoccupation with an imagined or exaggerated defect in physical appearance. The preoccupation is not accounted for by anorexia nervosa |
|
Definition
|
|
Term
| One or more unexplained symptoms or deficits affecting voluntary motor or sensory function and suggesting a neurologic etiology. The symptom is produced or preceded by psychological stress or conflict. Often appear relatively unconcerned about their deficit. |
|
Definition
|
|
Term
| o 28-year-old woman experiences a sudden loss of vision but appears unconcerned. Medical tests are essentially normal. The patient reports that just before the onset of her blindness, she saw her child dart out into the street. |
|
Definition
|
|
Term
| the preoccupation with the fear of having, or the idea that one has, a serious disease based on the person's misinterpretation of bodily symptoms or bodily functions. Fear persists despite negative medical findings and physician's reassurance |
|
Definition
|
|
Term
| a polysymptomatic disorder that begins before age 30 years, extends over a period of years, and is characterized by a combination of pain, gastrointestinal, sexual, and pseudo-neurological symptoms. |
|
Definition
|
|
Term
| o A 39-year-old woman has a 20-year history of somatic complaints such as headache (pain symptom), nausea (GI symptom), menstrual irregularities (sexual symptom), and temporary loss of sensation in her hands (pseudo-neurological symptom). She tells the doctor that she is always sick but that her previous doctors never seem to identify the problem and were unable to help her. |
|
Definition
|
|
Term
| o abdominal pain, fever (by heating the thermometer), blood in the urine (by adding blood from a needle stick), and seizures are some of the most common ___________ symptoms |
|
Definition
|
|
Term
| Why do people with factitious disorder often know how to fake symptoms realistically? |
|
Definition
| Typically, patients with factitious disorder have worked in the medical field and have specific knowledge of how to imitate medical illness realistically |
|
|
Term
| What frequently happened in the childhoods of people with factitious disorder? |
|
Definition
history of serious childhood illness that resulted in medical treatment or hospitalization in which the patient felt cared for and protected.
There also may be a history of childhood abuse or neglect. |
|
|
Term
| Muscle spindles are sensory structures located: |
|
Definition
| within the belly of a muscle |
|
|
Term
| What information do muscle spindles send to the spine? |
|
Definition
the degree of force the muscle is generating during the contraction
passive stretch information
(both of these contribute to proprioception) |
|
|
Term
| What sensory receptor prevents you from using too much force for the load (ex., picking up a pencil as though it were a brick & smacking yourself in the face)? |
|
Definition
|
|
Term
| nuclear chain fibers & nuclear bag fibers make up the _________________ |
|
Definition
|
|
Term
| Nuclear chain & nuclear bag fibers send a a tonic signal, but they also send a higher-frequency signal when the muscle they are in is passively stretched. Why do they also send more signal when the muscle is contracted? |
|
Definition
they have a contractile portion on each end and non-contractile portion in the middle
when the muscle ends contract (along with rest of muscle), the middle stretches
this stretching causes the signal |
|
|
Term
| non-contractile sensory receptor found in tendon |
|
Definition
| golgi tendon organ receptors |
|
|
Term
| signals too much tension in the muscle (whether from passive or active stretch) |
|
Definition
| golgi tendon organ receptors |
|
|
Term
| reflex that causes muscles to relax & lengthen when there is too much skeletal muscle contraction (which could cause tendons to tear) |
|
Definition
|
|
Term
| What is the pathway of the golgi tendon reflex? |
|
Definition
| Golgi tendon organs perceive excessive force within muscle-->excite interneurons in spine-->inhibit alpha motor neuron-->stop exciting muscle-->muscle stops contracting |
|
|
Term
| What receptors are involved in the stretch reflex? |
|
Definition
|
|
Term
| What is the pathway of the stretch relfex |
|
Definition
Muscle spindles perceive stretch-->excite alpha motor neurons-->excite muscle to contract
(note: no spinal interneurons) |
|
|
Term
| Unlike the golgi tendon reflex, the stretch reflex doesn't have: |
|
Definition
|
|
Term
| motor neurons that innervate muscle fibers throughout the muscle |
|
Definition
|
|
Term
| motor neurons that innervate specialized muscle fibers (nuclear chain fibers & nuclear bag fibers) within the muscle spindle |
|
Definition
|
|
Term
| What is the pathway of the flexor withdrawel reflex? |
|
Definition
| nociceptive stimulus at limb-->sensory neurons-->interneurons in spine-->ipsilateral alpha motor neuron-->excite flexor muscles to withdraw limb |
|
|
Term
| What is the pathway of the crossed-extensor reflex? |
|
Definition
The crossed extensor reflex is seen at the same time as the flexor withdrawal reflex:
nociceptive stimulus at limb-->sensory neurons-->interneurons in spine-->ipsilateral alpha motor neuron-->excite flexor muscles to withdraw limb
The interneurons in the spine also have a branch that crosses the spine, leading to the crossed-extensor relfex:
spinal interneurons-->contralateral alpha motor neuron-->excite extensor muscles to extend opposite limb to stabilize uninjured side of body
also,
sensory neurons-->CNS-->shift center of gravity to maintain balance |
|
|
Term
| The CNS usually has a(n) _____________ effect on spinal reflexes |
|
Definition
inhibitory
(that's why people with UMN lesions have hyperreflexia, + Babinski sign, jaw reflex, and clasp knife spasticity) |
|
|
Term
| During the part of the gait cycle when the heel touches the ground, what are the actions of the Tibialis anterior, Extensor hallucis longus, and Extensor digitorum longus? |
|
Definition
Tibialis anterior dorsiflexes ankle
Extensor hallucis longus dorsiflexes big toe
Extensor digitorum longus dorsiflexes rest of toes |
|
|
Term
| During the part of the gait cycle when the foot rotates from only the heel touching the ground to being flat, what are the actions of the Tibialis anterior, Extensor hallucis longus, and Extensor digitorum longus? |
|
Definition
All of them release slowly so that foot doesn't slap ground.
Tibialis anterior dorsiflexes ankle
Extensor hallucis longus dorsiflexes big toe
Extensor digitorum longus dorsiflexes rest of toes |
|
|
Term
| What are the actions of the triceps surae, flexor hallucis longus, & flexor hallucis brevis during toe-off? |
|
Definition
triceps surae (part of the gastrocnemius) pushes off for the swing phase
flexor hallucis longus & brevis forcibly flex big toe to push off
(loss of these muscles radically impairs gait cycle, causing a limp) |
|
|
Term
| During the swing phase of the gait, the ___________________ muscle dorsiflexes the ankle |
|
Definition
|
|
Term
| A lesion in the common fibular nerve (aka common peroneal nerve) leads to deficits in what 3 muscles, causing foot drop? |
|
Definition
Tibialis anterior--dorsiflexes ankle
Extensor hallucis longus--dorsiflexes big toe
Extensor digitorum longus--dorsiflexes rest of toes |
|
|
Term
| What changes do deficits in the fibularis longus and brevis cause in gait? |
|
Definition
| causes dragging the lateral margin of the foot while walking (Shows as uneven wear on soles of shoes) |
|
|
Term
|
Definition
continuous passive stretch causes initial resistance, then release of resistance
Associated with spasticity
A manifestation of uninhibited polysynaptic flexion reflexes |
|
|
Term
| inhibitory interneurons in the spinal cord; form a negative feedback loop with alpha motor neurons |
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Definition
Renshaw Cells
Alpha neuron sends an excitatory collateral to Renshaw cells (“Hey, I’m activating the muscle now!”)
Renshaw cell inhibits alpha neuron (“Okay, so stop activating.”) |
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Term
| progressive, fluctuating tonic contraction (especially of the axial musculature) because alpha neuron continuously activates muscle fibers |
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Definition
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Term
| Disinhibition of Renshaw cells or disinhibition of gamma-motor system will cause __________________ syndrome |
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Definition
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Term
| What is the function of reticulospinal tracts? |
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Definition
| postural adjustment and maintenance of balance |
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Term
| What is the function of the tectospinal tract? |
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Definition
| Reflex of turning the head toward visual stimuli |
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Term
| What is the function of the lateral vestibulospinal tract? |
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Definition
| upright posture, postural changes in response to body tilt/movement |
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Term
| What is the function of the medial vestibulospinal tract? |
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Definition
| Medial: head and trunk positions in response to vestibular stimulus, stabilizes head when we walk, coordinate head and eye movement |
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Term
| The function of the __________________ tract is voluntary motor action – precise, speedy, skilled movements (e.g. individual digits) |
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Definition
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Term
| The _____________________ in the brain sends a signal down the __________________ tract that excites inhibitory interneurons in spine, which inhibits spinal reflexes |
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Definition
medullary reticular formation
reticulospinal |
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Term
| Without input from the medullary recticular formation, the lateral vestibular tract & pontine reticulospinal tract send signals to the spine that: |
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Definition
| increase motor neuron excitability |
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Term
| Descending ____________ & _____________ reticulospinal tracts inhibit spinal reflexes. |
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Definition
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Term
Posturing and abnormal movement patterns-extensor thrusts, blocks
Oropharyngeal problems-tongue thrusts, grimacing, swallowing difficulties
Strabismus
Tone-increased or decreased in muscles
Evolutional responses-persistent primitive reflexes or failure to develop equilibrium
and protective responses
Reflexes-increased deep tendon reflex and extension of the toes during plantar reflexes |
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Definition
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Term
an abnormal gait commonly seen in spastic cerebral palsy due to excessive
contraction of the hip adductors and internal rotators |
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Definition
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Term
| Divergent strabismus, abducens nerve palsies, and impaired upwards gaze |
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Definition
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Term
| What happens to the gaze with severe hydrocephalus? |
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Definition
conjugate deviation of the eyes downward so that the inferior half of the iris is hidden by the lower
eyelid (“sunsetting sign”) |
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Term
| What kind of drug is gentamicin? |
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Definition
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Term
| What are aminoglycosides like gentamicin used to treat? |
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Definition
| used for serious aerobic gram negative infections |
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Term
Aminoglycosides like gentamicin can cause
_____________toxicity
_____________toxicity
_____________toxicity |
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Definition
vestibular toxicity
ototoxicity
nephrotoxicity (renal toxicity) |
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Term
A person who is taking gentamicin (aminoglycoside) starts developing the following symptoms
precipitous onset of unrelenting dizziness, with nausea, vomiting, and ataxia
symptoms increase with head motion
They say "it’s like walking around with a shaky camera".
What are you worried about? |
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Definition
vestibular toxicity
(gets worse with head motion b/c they don’t have vestibule-ocular reflex to adjust eyes for head motion) |
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Term
An elderly person with renal insufficiency must take gentamicin (aminoglycoside) to treat a severe gram negative infection.
What are you most worried about? |
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Definition
| nephrotoxicity (renal toxicity) |
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Term
| How does gentamicin (aminoglycoside) cause vestibular toxicity |
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Definition
aminoglycosides chelate iron via a redox reaction. The redox reaction generates oxidative free radicals, which cause hair cell apoptosis
In the vestibular organ aminoglycosides destroy hair cells in the ampulae of semi-circular canals.
in the cochlea, aminoglycosides destroy the auditory sensory cells of the organ of Corti, starting at the outer hair cells (high-frequency hearing loss), then proceeds toward the inner turns (low frequency hearing loss). |
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Term
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Definition
| formation of 2 or more separate bonds between a molecule & a central atom |
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Term
| Explain the difference between time-dependent & concentration-dependent bactericidal effects |
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Definition
time-dependent: Bacteria are killed at the same rate & extent as long as Minimum Bactericidal Concentration (MBC) is maintained
(most antibiotics, such as beta-lactams & vancomysin, are time-dependent)
concentration-dependent: Minimum Bactericidal Concentration is much less than maximum bactericidal concentration
so it's more important to get a shock of high concentration than to maintain a low concentration for longer periods of time.
(aminoglycosides) |
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Term
| Do aminoglycosides like gentamicin have time-dependent or concentration-dependent bactericidal effects? |
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Definition
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Term
| How do you dose aminoglycoside (gentamicin) and why? |
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Definition
high, once-daily dose
Aminoglycosides' effects are concentration-dependent, not time-dependent, so it's better to get a big shock of aminoglycoside once a day, than several medium doses throughout the day
You can't have both because aminoglycoside causes vestibular toxicity (and also ototoxicity & nephrotoxicity)
Once-daily dosage, allows drug level to fall and body can repair damage before it becomes permanent |
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Term
| Balance relies on 3 kinds of inputs. What are they? (Generally you can make do with any 2 of the 3). |
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Definition
proprioception
vision
vestibular
(Normally, when you close your eyes, vestibular input & proprioception take over. The Romberg test indicates problems with proprioception or vestibular input) |
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Term
| What cranial nerve deals with pupil dilation & constriction, and what happens if there is a lesion to that nerve? |
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Definition
CN III Oculomotor
A lesion to the occulomotor nerve leads to pupil dilation
(as well a complete ptosis & the gaze being stuck down & out) |
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Term
| What cranial nerve innervate the muscle that raises and lowers the eyelid, and what does lesion to this nerve cause? |
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Definition
CN III Oculomotor
complete ptosis
(also, pupil is dilated & eye is stuck down & out) |
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Term
During the crossed-extensor reflex, the limb ipsilateral to the painful stimulus is withdrawn and the controlateral limb is extended.
A signal is also sent to the CNS in order to: |
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Definition
| shift the center of gravity to maintain balance |
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Term
Explain the following mnemonic:
Lateral Jack Horner
Runs through the town
Can’t feel cold or pain now
In his nightgown.
PEAKING through the windows…. |
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Definition
Lateral Medullary Syndrome of Wallenberg causes
contralateral loss of pain & temp to body
ispilateral Horner syndrome
is caused by stroke of PICA (posterior inferior cerebellar artery) |
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Term
| Why does ototoxicity from aminoglycosides causes high-frequency hearing loss first. |
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Definition
aminoglycosides chelate iron via a redox reaction. The redox reaction generates oxidative free radicals, which cause hair cell apoptosis
in the cochlea, the free radicals destroy the auditory sensory cells of the organ of Corti, starting at the outer hair cells (high-frequency hearing loss), then proceeds toward the inner turns (low frequency hearing loss) |
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