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268 Cards in this Set
- Front
- Back
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Mental Status Exam determines
3 general things |
level of consciousness
overall intellectual function interaction of cerebral hemispheres |
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Mental Status Exam determines
6 specific things |
level of alertness
orientation memory affect intellect judgement |
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Causes of ACUTE reduction in mental status (3)
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metabolic encephalopathy (drugs, acute organ failure)
trauma infection/abnormality involving both hemispheres |
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Causes of chronic, slow redution of mental status (3)
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progressive organ failure (e.g.: liver/kidney ds)
TIAs neurodegenerative disease |
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2 scent tests (substance and CN it tests)
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ammonia tests CN 5
aromatic like coffee or ginger tests CN 1 |
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5 things to test RE: optic nerve
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acuity
color pupil function visual fields appearance of optic nerve head |
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What is particularly important to assess for when ruling out optic nerve lesion in patients w/
reduced acuity in one eye + normal fundoscopy |
pupil function
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visual field analysis helps determine abnormalities in (5 things)
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eye
optic nerve chiasm optic tracts visual radiations |
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If you do not test visual fields, what might you miss?
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the absence of up to an entire occipital lobe!~
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retina and optic nerve lesions cause...
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a deficit in one eye
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chiasm lesions cause...
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bitemporal hemianopsia (blindness in 1/2 of visual field)
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lesions after the chiasm cause...
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contralateral visual field loss in each eye
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nerve innervating lateral rectus
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abducens (CN 6)
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nerve innervating superior oblique
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trochlear (CN 4)
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nerve innervating all other ocular motility
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oculomotor (CN 3)
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horizontal diplopia =
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double vision
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horizontal diplopia implies a problem with...
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lateral or medial recti muscles
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vertical diplopia implies a lesion of...
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superior or inferior recti or oblique muscles
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3 targests of trigeminal nerve (CN5)
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facial sensation
tongue sensation (NOT taste) muscles of mastication |
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muscles of mastication innervated by CN 5
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medial and lateral pterygoids
temporalis masseter |
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upper motor neuron (UMN) lesion spares what part of the face?
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superior
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lower motor neuron (LMN) lesion involves what part of the face
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superior
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How does emotional smile vs. volitional smile help determine UMN from LMN?
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Even with severe UMN facial wkness, during emotional smile, weakened side will partially function
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Effect of LMN lesion on taste
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loss of taste to anterior 2/3 of tongue on same side as nerve lesion (sweet, sour, salty)
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Effectof LMN lesion on hearing
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hyperacusis (abnormally sensitive hearing)
due to loss of innervation to stapedius muscle in ipsilateral ear |
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proximal facial nerve lesion can cause...
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loss of tearing function
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function of vestibular part of CN 8
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balance, feeling of stability
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function of cochlear part of CN 8
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perception of sounds
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4 functions of glossopharyngeal/vagus nerves
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palate sensation and control
vocal cord control taste sensation posterior tongue parasympathetic function like vagal control of heart |
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right sided CN 9/10 lesion deviates palate to the ____ side
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LEFT
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2 muscles innervated by spinal accessory nerve
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trapezius
SCM |
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lesion of RIGHT spinal accessory nerve causes head to deviate to the ___ side
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RIGHT
(b/c innervation to left SCM stronger) |
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Motor function of hypoglossal nerve
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protrudes tongue
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lesion of LEFT hypoglossal nerve cuases tongue to deviate to the ____
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LEFT
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which nerves are actual extensions of the brain?
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CN 1
CN 2 |
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cranial nerves that are lower motor neurons
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CN 3 - CN 12
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midbrain = mostly ___ & ____ CN
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midbrain = mostly 3rd & 4th CN
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Pons = mostly ___ through ____ CN
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Pons = mostly 5th through 8th CN
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Medulla = mostly ___ through ____ CN
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Medulla = mostly 9th through 12th CN
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which CNs go through cavernous sinus?
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II, IV, V-1, VI
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which CNs are located at the ponto-cerebellar angle?
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7 & 8
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which CNs are around the temporal bone?
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5, 6, 8
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which CNs are around the jugular foramen?
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9, 10, 11
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brainstem lesions usually cause ____ signs
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brainstem lesions usually cause CROSSED signs
(body abnormality contralateral to lesion) |
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UMN lesion over entire limb(s) leads to ____ reduction of bulk
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mild
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LMN lesion in specific nerve distribution leads to _____ reduction of bulk
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severe
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wrist drop with triceps weakness implies lesion of which nerve
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radial nerve
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weakness of both legs associated with spacticity and not other deficits imply what type of lesion?
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usually: spinal cord lesion
rarely: interhemispheric lesion involving medial aspect of both frontal lobes |
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weakness of face, arm and leg muscles imply lesion in...
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usually: opposite hemisphere
rarely: midbrain |
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which type of lesion (UMN/LMN) has
spasiticity, hyperreflexia, extensor toe sign |
UMN
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which type of lesion (UMN/LMN) has
flaccidity, fasiculations, hyporeflexia |
LMN
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distinguishing characteristics of UMN lesions vs. LMN lesions
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spasticity, hyperreflexia, extensor toe sign
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distinguishing characteristics of LMN lesions vs. UMN lesions
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flaccidity, fasiculations, hyporeflexia
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describe neural lesions associated with Myasthenia Gravis
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myoneural junction abnormalities
--> widespread weakness in many skeletal muscles |
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describe lesions associated with diabetes or Guillian Barre (AIDP)
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PNS lesions
glove and stocking distribution weakness |
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lesions associatged with ALS
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UMN and LMN lesions in same limb
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Muscular dystrophy causes...
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weakness in muscles through out the body
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tone differences between UMN and LMN lesion
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spasticity implies UMN lesion
lack of tone implies LMN lesion |
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type of lesion associated with cogwheel rigidity
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basal ganglion/substantia nigra lesion
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cell groups in basal forebrain that control and tune movement
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basal ganglion/substantia nigra
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cerebellar lesion can cause what type of tone abnormality?
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hypotonia
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resting tremor implies...
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basal ganglion/substantia nigra defect
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Describe Parkinson's resting tremor
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three to five cycle tremor
can be associated with cogwheel rigidity |
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intention tremor =
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occurs with voluntary movement
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type of lesion associated with intention tremor
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vestibulo-cerebellar lesion
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positional tremor is considered "physiologic tremor" if relieved by...
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beta blockers or alcohol
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2 functions of pyramidal system
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allows initiation of movement
helps guide strength and direction of movement |
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definition of extrapyramidal system
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any motor system that is not part of the pyramidal system
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function of extrapyramidal system
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helps coordinate and smooth movement
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Two major subunits of sensation
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heat, cold, pain and touch
motion, vibration, position sense |
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anterolateral spinal thalamic system carries information through what structure?
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spinal cord
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anterolateral spinal thalamaic system is associated with which branch of sensation?
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heat, cold, pain and touch
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path of anterolateral spinal thalamic system
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crosses in center of spinal cord
ends in thalamus |
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structures that transmit motion, vibration and position sense
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posterior columns
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where do posterior columns cross?
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in medulla
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2 uses of deep tendon reflexes
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help discriminate UMN from LMN lesions
helps located spinal cord level involved with deficits |
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4 major deep tendon reflexes
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ankle jerk
knee jerk biceps jerk triceps jerk |
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ankle jerk tests which spinal level?
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S1
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knee jerk tests which spinal levels?
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L4
L2, L3 |
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biceps jerk tests which spinal levels?
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C5, C6
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triceps jerk tests which spinal level?
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C7
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5 methods to test toe sign
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Babinski
Conda Oppenheim Chaddock Schutta |
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Normal toe sign
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Babinski maneuver should cause the great toe to plantar flex after age 1
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extensor toe sign after age 1 implies....
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UMN involving pyramidal system supplying that foot
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thumb sign, aka:
reflex |
Hoffman sign
brisk adduction of thumb when abducted |
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cremasteric and anal reflex help determine...
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sacral spinal cord function
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3 signs of widespread frontal lobe dysfunction, e.g.: Alzheimer's
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Glabella sign
palmamental sign suck response |
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Glabella sign
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forced eyelid closure when striking Glabella
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Glabella sign present in which two neuro diseases?
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Alzheimer's
Parkinson's |
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Coordination and Gait tests which four things?
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vestibulo-cerebellar function
both sensory systems pyramidal system extrapyramidal system |
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Coordination is a reliable test for cerebellar function ONLY when...
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strength is essentially intact
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test that implies cerebellum functioning well
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smooth finger to nose function
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what does heel-to-shin test?
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whether spino-cerebellar function is intact
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A person with history of metastatic cancer and current good leg strength in bed, but with a bizzare gait has ________ until proven otherwise.
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metastatic disease in the spinal cord
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Why walking a patient different than testing leg strength in bed?
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expose subtle weaknesses
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loss of an odd gait when person walking backward implies...
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hysteric weakness
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tandem gait exposes which two things
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strength
vestibular-cerebellar function |
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Definition of station
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ability to stand still with eyes open and with eyes closed
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loss of station with eyes open and without weakness may be due to____
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cerebellar lesion
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loss of station, esp. with eyes closed, may be due to ____
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loss of sensation
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first step in caring for patients with neuro disorders
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establish location of lesion
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4 lobes comprising the
CEREBRAL CORTEX |
frontal lobe
parietal lobe temporal lobe occipital lobe |
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corona radiata is made of...
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white matter tracts
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tracts on the way to or from the brain stem are the...
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internal capsule
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3 regions of the brainstem
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midbrain
pons medulla |
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5 regions of the spinal cord
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lateral location of the pyramidal system (motor)
anterolateral spinothalamic tracts (heat, cold, pain, touch) posterior columns (motion, vibration, position) spinocerebellar tracts grey matter or white matter |
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peripheral motor nerve starts at _____
and goes uninterrupted to ______ |
SPINAL CORD or BRAINSTEM
goes to TARGET MUSCLE SYNAPSE |
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sensory nerve emerges from ______
and goes uninterrupted to the ______ |
emerges from SENSORY RECEPTOR
goes uninterrupted to the SENSORY NUCLEUS |
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The LEFT hemisphere of the CNS runs the motor and sensory function for the _____ side of the body
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RIGHT (contralateral)
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The INFERIOR part of the lateral frontal lobe supplies innervation for the ______
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muscles of the face (SUPERIOR)
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As you move superiorly in the frontal lobe, you find the nerves that supply more ______ parts of the body
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INFERIOR
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Ventral structures are usually involved in ____ function
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MOTOR
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Exception to the left brain - right body rule
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cerebellum
functions on ipsilateral side |
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final common pathway of motor neuron
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lower motor neuron
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where does lower motor neuron begin?
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at nucleus level in spinal cord or brainstem
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pyramidal system, aka:
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corticospinal tract
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pyramidal system carries the signals for...
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initiating movement from the motor CORTEX down
then crossing to the opposite side motor centers in anterior SPINE |
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where do pyramidal system signals cross
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lowest part of the medulla
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clinical manifestations of UMN lesion
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weakness
spasticity hyperreflexia extensor toe sign during Babinski maneuver |
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tract that helps initiate movement
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pyramidal system
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What does "involvement of the pyramidal system causes a UMN lesion" mean?
|
??
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corticobulbar tract carries what type of signals?
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motor signals
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corticobulbar tract carries motor signals from the ____ to the _____
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from CORTEX to BRAINSTEM
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Brainstem, aka:
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bulbar area
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motor signals in the cortico bulbar tract synapse where?
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in the cortex
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corticobulbar tract provides signals from the ____ to the _____
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corticobulbar tract provides signals from the CORTEX to the MOTOR CRANIAL NERVES
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where does corticobulbar tract cross?
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in the brainstem
above pyramidal decussation close to cranial nerve it supplies |
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what type of signals does the spinothalamic tract carry?
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sensory
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the spinothalamic tract carries sensory signals from the ______ to the _______
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from the LATERAL SPINE
to the OPPOSITE THALAMUS |
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sensory relay station in the middle portion of the brain
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thalamus
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spino thalamic tract carries which 4 sensations?
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heat
cold pain touch |
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where do spinothalamic signals cross?
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just a few levels from where the information enters spinal cord
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spinothalamic signals go from the body, through the thalamus, and to the _____
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parietal lobe
contralateral from the side of the body where signal originated |
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trigeminal system carries ____ information from the ____ to the ____ on the way to the _____
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trigeminal system carries SENSORY information from the FACE to the THALAMUS on the way to the PARIETAL LOBE.
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Dorsal column-medial lemniscal system =
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posterior columns:
fasciculus gracilis (legs) cuteatus (arms) |
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System knows as Most Valuable Player
|
Dorsal column-medial lemniscal system =
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Dorsal column-medial lemniscal system carries which 3 sensations
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motion
vibration position (MVP) |
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Dorsal column-medial lemniscal system carries signals from the _____ to the ______
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from the posterior spinal cord
to the opposite thalamus |
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where do signals in the dorsal column-medial lemniscal system cross?
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medulla
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testing the dorsal column-medial lemniscal system is used to distinguish what?
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spinal cord lesions and hemisphere lesions
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3 major sections of brainstem
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midbrain
pons medulla |
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does the extrapyramidal motor system initiate movement?
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no
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2 parts of extrapyramidal motor system
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basal ganglion
substantia nigra |
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where is language-production center almost always located?
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left frontal lobe
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where is language-understanding center almost always located?
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left temporal lobe?
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who may have some/all language function in right hemisphere?
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left-handed people
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the ability to produce sounds is a _____ function
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medullary
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widespread even in both cerebral hemispheres is commonly called...?
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encephelopathy
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definition of UMN lesions
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involvement of the pyramidal system somewhere along the pathway from the cortex to above the nucleus of the final common pathway
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clinical symptoms of UMN lesions
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widespread weakness, involving more than one/few peripheral nerves
hyperreflexia spasticity extensor toe signs during Babinski |
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LMN lesions are usually caused by involvement of...
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the nucleus of the nerve as it originates in the spinal cord
or the actual peripheral nerve itself |
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clinical symptoms of LMN lesions
|
weakness in muscles in precise distribution of specific nerve systems
hyporeflexia hypotonia flexor/silent toe signs during Babinski |
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loss of motion, viration and position sense in one leg
& heat, cold, pain, touch in the other leg is due to... |
spinal cord disease on an entire lateral half of the spinal cord
|
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Brown-Sequard Syndrome
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loss of MVP on one leg
and loss of heat, cold, pain, touch in other leg |
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loss of sensation in band-like distribution implies...
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involvement of specific spinal dermatome
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numbness along entire arm from neck to fingers implies
|
cervical spine lesion
|
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numbness around nipple area imples
|
T4 lesion
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numbness around the umbilicus implies
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t10 lesion
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numbness from low back down entire leg implies
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lumbosacral lesion
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suck response implies...
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widespread bifrontal lobe lesion
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movement of lower jaw when palm is stroked with an object =
|
palmamental sign
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palmamental sign is reflective of what type of lesion?
|
frontal lobe
|
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motor output is the function of what 3 inputs?
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sensory (reflexive)
cognitive (voluntary) intrinsic |
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StAR
|
steroidogenic acute regulatory protein
|
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function of StAR
|
transports chl across outer mitochondrial membrane
|
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positive regulation of StAR
|
by LH
if no LH, essentially no StAR |
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which step in steroid biosynth is the rate limiting step?
what catalyzes the RLS? |
first step
catalyzed by CSCK |
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CSCK stands for...
|
choloesterol side chain kinase
|
|
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major secretory hormone in females
|
progesterone
|
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where is DHEA produced
|
adrenals
|
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androgens produced in adrenals contribute significantly in _____, but not in _____
|
contribute significantly in FEMALES, but not in MALES
|
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do gonads have enzymes that convert intermediates to mineralcorticoids or glucocorticoids?
|
no
|
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DHEA is a precursor for which two hormones?
|
DHT
testosterone |
|
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enzyme that converts DHT to testosterone
|
5-alpha reductase
|
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DHT binds to the same androgen receptor as _____, but has much ____ biological activity
|
DHT binds to the same androgen receptor as TESTOSTERONE
but has much GREATER biological activity |
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reversible chain of 4 androgens
|
DHT <--> testosterone <--> androstenedione <--> DHEA
|
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all estrogens are...
synthesized from ____ catalyzed by _____ and regulated by _____ |
all estrogens are
sythesized from ANDROGENS catalyzed by AROMATASE and regulated by FSH |
|
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3 forms of estrogen
|
estradiol --> estrone --> estriol
(progressively less active; estriol found almost exclusively in pregnant women) |
|
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free concentration of androgens/estrogens?
|
1-10%
|
|
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relevant concentration for biological activity?
|
free + albumin-bound steroids
|
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progesterone is transported bound to ___
|
CGB
|
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steroid-receptor complex in cell nucleus acts as a ____
|
transcription factor
|
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high levels of either androgen or estrogen can bind the _____ receptor
|
"wrong" receptor
|
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In females, estrogen _____ the number of progesterone receptors
|
INCREASES
|
|
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In females, progesterone can ____ the number of estrogen receptors
|
DECREASES
|
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True or False: steroids can regulate the receptors of other steroids?
|
TRUE
|
|
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non-gonadal tissues that produce steroids
|
adrenal cortex
skin adipose tissue |
|
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steroids are converted into excretory metabolites in the ___
|
liver
|
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|
transport proteins slow down...
|
liver catabolism & renal loss
of steroid metabolites |
|
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Skeletal muscle has androgen receptors &
lacks aromatase or 5-alpha reductase so, anabolic growth is mediated by _____ |
testosterone
|
|
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sebaceious gands have androgen receptors
and 5-alpha reductase so androgen effects are mediated by _____ |
DHT
|
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CNS masculinization by androgens is mediated by ____ & _____
|
intracellular aromatase
estrogen receptors |
|
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Liver has which steroid receptors and enzymes?
|
androgen receptors
estrogen receptors aromatase |
|
|
Sexually dimorphic traits arise from differences in
|
androgen/estrogen ratios
|
|
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hypothalamic neurons release which hormone from which nuclei?
|
GnRH from arcuate and preoptic nuclei
|
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function of GnRH
|
increases synthesis and release of the gonadotropic hormones LH and FSH
|
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GnRH enters the_____ of the hypothalamus and binds to receptors on the ______
|
enters the PORTAL SYSTEM
binds to receptors on the GONADOTROPHS |
|
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HPG axis
|
hypothalmus - pituitary - gonadal axis
|
|
|
pathways originating in which 4 neural regions converge on hypothalamus?
|
limbic system
thalamus cerebral cortex reticular activating systems (diurnal rhythms) |
|
|
major inhibiting pathways are mediated by which neurotransmitter?
|
GABA
|
|
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major excitatory pathways are mediated by which neurotransmitter?
|
glutamate
|
|
|
4 pathways can be excitatory or inhibitory
|
doapminergic
endorphinergic adrengergic serotonergic |
|
|
steady, as opposed to pulsatile, release of GnRH is _____ to pituitary, due to ______
|
INHIBITORY to pituitary
due to down regulation of receptors |
|
|
most GnRH levels are inferred from ______
|
LH levels
|
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GnRH stimulates the secretion of ___ and ____
|
LH
FSH |
|
|
Function of LH in gonads
|
increases synthesis of androgens
|
|
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Function of FSH in gonads
|
increases synthesis of estrogens (aromatase)
and inhibin, activin, follistatin (regulatory proteins) |
|
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type of LH and FSH receptors in gonads
|
G-coupled transmembrane proteins
|
|
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inhibin and activin are both members of what family?
|
TGF-beta
|
|
|
Function of inhibin
|
inhibits FSH secretion in anterior pituitary
|
|
|
Function of activin
|
stimulates FSH secretion in anterior pituitary
|
|
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Function of follistatin
|
activin binding protein
reduces available activin by competitive inhibition |
|
|
what hormones inhibit LH and FSH at pituitary and hypothalamic levels?
|
androgens and estrogens
|
|
|
primary negative feedback hormone in HGP axis in MALES
|
androgens
|
|
|
primary negative feeback hormone in HGP axis in FEMALES
|
estrogens
|
|
|
inhibin, activin and follistatin are secreted by gonads and _____
|
pituitary cells
|
|
|
time length of G1 phase
|
12 hours to entire lifetime
|
|
|
time length of S phase
|
up to 10 hours
|
|
|
two cell types arrested in G2 phase
|
primary oocyte
cardiac muscle fibres |
|
|
time length of M phase
|
1 hour
|
|
|
(Xn, Yc) for Prophase
Metaphase Anaphase |
Prophase (2n, 4c)
Metaphase (2n, 4c) Anaphase (4n, 4c) |
|
|
Meiosis I =
|
Reductional Division
|
|
|
During Meiosis I, chromosome number of gamete is...
|
halved from 2n to 1n
|
|
|
During Meiosis I, DNA content is halved from...
|
4c to 2c
|
|
|
at the end of Meiosis I, gamete nucleus is (Xn, Yc) and daughter cells are called _____ or _____
|
at end of Meiosis I
gamete nucleus 2n, 1c secondary spermactocyte or secondary oocyte |
|
|
Meiosis II
|
Equatorial Division
|
|
|
Describe Meiosis II
|
beginning with 1n, 2c
separates sister chromatids at end, gamete = 1n, 1c |
|
|
visceral layer of tunica vaginalis testis is derived from...
|
extension of the peritoneal outpouching from abdominal cavity
|
|
|
tunic albuginea
|
dense connective tissue capsule
|
|
|
mediastinum testis
|
thickened posterior part of tunica albuginea
contains rete testis |
|
|
paminiform venous plexus lowers testicular temperature to ____
|
35*C under normal conditions
|
|
|
function of cremaster reflex in response to cold
|
draw testes up toward body
|
|
|
cryptorchidism
|
failure of testes to descend, usually failure to descend through inguinal canal
|
|
|
prevalence of crytporchidism
|
1% of one-year-old boys
|
|
|
undescended testes can be vulnerable to ____
|
trauma
|
|
|
what hormone controls descent of testes?
|
Antimullerian Hormone from Sertoli cells
& androgens |
|
|
Lobules of testes separated by ____
|
septa emerging from mediastinum testis
|
|
|
what does each lobule of testis include
|
1-4 seminiferous tubules
plus loose CT |
|
|
Stats on seminiferous tubules
|
1000 in both testes
each tubule ~80cm long each testes contains about 0.5 miles in length of tubules |
|
|
site of sperm formation
|
seminiferous tubules
|
|
|
site of testosterone synthesis
|
seminiferous tubules
|
|
|
sperm formation and testosterone synthesis are controlled by hormones from the _____
|
anterior pituitary
|
|
|
straight tubule
|
end of each seminiferous tubule
|
|
|
rete testis
|
anastamosing channels into which the straight tubules empty
|
|
|
primordial germ cells arise from the _________ of the ______ in Week ___
|
primordial germ cells arise from the EPIBLAST LAYER of the BILAMINAR DISK in WEEK 2
|
|
|
primordial germ cells enter the ____ during Week ____
|
primordial germ cells enter the yolk sac during Week 3
|
|
|
gastrulation of the embryo occurs in the ___ week
|
3rd
|
|
|
During gastrulation, primordial germ cells migrat from the yolk sac to the ____
|
embryo proper
|
|
|
route through which primordial germ cells travel from yolk sac to embryo proper
|
dorsal mesentery of the hindgut
|
|
|
gonadal ridges
|
final location of migrating primordial germ cells
located bilaterally to the gut tube |
|
|
primordial germ cells divide by mitosis into ____
|
spermatogonia or oogonia
|
|
|
2 histological regions of gonadal ridge
|
cortex
medulla |
|
|
where does gonadal ridge form?
|
paravertebrally around L1-L2
|
|
|
cortical region of the gonadal ridge is subjacent to _____
|
overlying peritoneum of the posterior abdominal wall
|
|
|
what does the medulla of the gonadal ridge contain?
|
growing gonadal cords
|
|
|
during which week are primordial germ cells incorporated into the gonadal cords?
|
week 6
|
|
|
indifferent gonads
|
gonads without sexual differentiation (before week 7)
|
|
|
what does male differentiation of the gonads require
|
SRY
|
|
|
SRY
|
Sex determining Region on the short arm of the Y chromosome
|
|
|
two cell types specific to male gonad
|
Sertoli cells
Leydig cells |
|
|
Protein coded for by SRY that determines male differentiation
|
Testis Determining Factor (TDF)
|
|
|
absence of Y chromosome results in formation of _____
|
ovary
|
|
|
Is primary female differentiation of female genital ducts and external genitalia dependent on hormones?
|
NO; will occur even if ovaries are absent
|
|
|
Week when Sertoli cells start secreting AMH?
|
Week 6-7
|
|
|
AMH supresses the development of which structure
|
Mullerian ducts (paramesonephric ducts)
which normally give rise to oviducts, uterus |
|
|
in the absence of AMH, what develops?
|
female genital ducts
(regardless of genotype of the individual) |
|
|
What hormones do Leydig cells secrete
|
testosterone
androstenedione |
|
|
are fetal Leydig cells metabolically active?
|
Yes
|
