Neurology Flashcards
Motor innervation of the tongue
Hypoglossal nerve – CN XII
w/ exception of palatoglossus muscle, which is innervated by the Vagus Nerve – CN X
General sensation (touch/pain/pressure/temp) to anterior 2/3 of tongue?
Mandibular branch of Trigeminal Nerve – CN V3
General sensation (touch/pain/pressure/temp) to posterior 2/3 of tongue?
Glossopharyngeal Nerve – CN IX
General sensation (touch/pain/pressure/temp) to posterior area of the tongue root?
Vagus Nerve – CN X
Gustatory sensation (taste buds) to anterior 2/3 of tongue?
Chorda Tympani of Facial Nerve – CN VII
Gustatory sensation (taste buds) to posterior 2/3 of tongue?
Glossopharyngeal Nerve – CN IX
Gustatory sensation (taste buds) to posterior area of the tongue root & taste buds of the larynx & upper esophagus?
Vagus Nerve – CN X
Afferent limb of pupillary light reflex?
transmits light → pretectal nucleus → Edinger Westphal nucleus
Optic Nerve (CN II)
Marcus Gunn pupil = afferent pupillary defect due to optic nerve damage or retinal detachment
Efferent limb of pupillary light reflex?
Pretectal nucleus → iris sphinctor & ciliary muscle → constricts pupil
Parasympathetic fibers of Oculomotor Nerve (CN III)
Afferent & efferent limbs of Corneal reflex?
A = CN V1 ophthalmic (nasociliary branch)
E = CN VII (temporal branch: orbicularis oculi)
Nerve that allows ability to close eyelid?
Facial Nerve (CN VII)
Where is lesion?
Medially directed eye that cannot abduct
Abducens nerve (CN VI)
Where is lesion?
Eye looks down & out, ptosis, pupillary dilation, loss of accommodation
Oculomotor Nerve (CN III)
Where is lesion?
Eye moves upward, particularly w/ contralateral gaze & ipsilateral head tilt
(problems going down stairs)
Trochlear Nerve (CN IV)
Where is lesion?
Horizontal nystagmus w/ normal convergence
MLF
Internuclear Ophthalmoplegia
Controls circadian rhythm?
Suprachiasmatic nucleus (Hypothalamus)
Controls heating, sympathetic?
Posterior Hypothalamus
Controls cooling, parasympathetic?
Anterior Hypothalamus
Controls satiety; lesion → hyperphagia?
Ventromedial area (Hypothalamus)
stimulated by Leptin
Controls huger; lesion → anorexia?
Lateral area (Hypothalamus)
NE → Location of synthesis?
Locus Ceruleus (Pons)
Dopamine → Location of synthesis?
Ventral Tegmentum & Substantia Nigra (SNc; midbrain)
5-HT → Location of synthesis?
Raphe Nucleus (Pons)
ACh → Location of synthesis?
Basal nucleus of Meynert
GABA → Location of synthesis?
Nucleus accumbens
Location?
Reward center, pleasure, addiction, fear
Nucleus Accumbens & Septal Nucleus
Intention Tremor = Characteristic lesion where in the brain?
= Cerebellar dysfunction
Hemiballismus = Characteristic lesion where in the brain?
Contralateral subthalamic nucleus
e.g. lacunar stroke
Chorea = Characteristic lesion where in the brain?
Basal ganglia
e.g. Huntington’s
Athetosis = Characteristic lesion where in the brain?
Basal ganglia
e.g. Huntington’s
Lesion Localization?
Kluver Bucy syndrome (hyperorality, hypersexuality, disinhibited behavior)
Amigdala (bilateral)
- ass’d w/ HSV-1
Lesion Localization?
Disinhibition & deficits in concentration, orientation, & judgment; may have re-emergence of primitive reflexes
Frontal lobe
Lesion Localization?
Spatial neglect syndrome
(agnosia of the contralateral side of the world)
Right parietal lobe
Lesion Localization?
Reduced levels of arousal & wakefulness
(e.g. coma)
Reticular activating system (midbrain)
Lesion Localization? Wernicke-Korsakoff syndrome - Confusion, ophthalmoplegia, ataxia - Memory loss (anterograde & retrograde amnesia) - Confabulation, personality changes
Mammilary Bodies (bilateral)
- ass’d w/ Thiamine (B1) deficiency & alcoholics
- can be precipitated by giving glucose w/out B1 to a B1-deficient patient
Lesion Localization?
May result in tremor at rest, chorea, or athetosis
Basal ganglia (Parkinson’s Disease)
Lesion Localization?
Intention tremor, limb ataxia, & loss of balance
Cerebellar hemispheres
- affects lateral limbs, ipsilaterally
Lesion Localization?
Contralateral hemiballismus
Subthalamic nucleus
Lesion Localization?
Truncal ataxia, dysarthria
Cerebellar vermis
- “centrally” located, affects “central” body
Lesion Localization?
Anterograde amnesia
Hippocampus
Lesion Localization?
Eyes look away from side of lesion
Paramedian Pontine Reticular Formation (PPRF)
Lesion Localization?
Eyes look toward lesion
Frontal eye fields
Lesion Localization?
Parinaud Syndrome - paralysis of conjugate vertical gaze
Superior Colliculi
e.g. pinealoma; pineal body lies just above the superior colliculi
What nerve root controls the Biceps reflex?
C5
What nerve root controls the Triceps reflex?
C7
What nerve root controls the Patella reflex?
L4
What nerve root controls the Achilles reflex?
S1
Which cranial nerve nuclei lie in the Midbrain?
CN III & IV
Which cranial nerve nuclei lie in the Pons?
CN V-VIII
Which cranial nerve nuclei lie in the Medulla?
CN IX, X, XII
Which cranial nerve nuclei lie in the Spinal Cord?
CN XI
Afferent & effent limbs of lacrimation reflex?
A = V1
(loss of reflex does not preclude emotional tears)
E = VII
Afferent & effent limbs of jaw-jerk reflex?
A = V3 (sensory - muscle spindle from masseter)
E = V3 (motor - masseter)
Afferent & effent limbs of pupillary light reflex?
A = II
E = III
Afferent & effent limbs of gag reflex?
A = IX
E = X
Lesion Localization?
Paralysis of upper & lower face
CN VII, LMN
- Ipsilateral
(Facial nerve palsy)
Lesion Localization?
Paralysis of lower face w/ forehead spared
Lesion of motor cortex OR corticobulbar tract (cnxn btwn cortex & CN VII)
- Contralateral, UMN
- Forehead sparing due to bilateral UMN innervation
Lesion Localization?
Jaw deviation to one side
Ipsilateral CN V
unopposed force from opp. pterygoid muscle
Lesion Localization?
Uvula deviation to one side
Contralateral CN X
Lesion Localization?
Weakness turning head to one side w/ shoulder droop on other side
CN XI lesion on side of shoulder droop (trapezius)
- SCM causes weakness turning head
Lesion Localization?
Tongue deviation to one side
Ipsilateral CN XII lesion
Lesion Localization?
“Waiter’s tip”
(Limb hangs by side, medially rotated, forearm pronated)
Upper Trunk of Brachial Plexus (C5 & C6 roots)
- Lesioned by trauma (seen in infants w/ trauma following delivery)
- Paralysis of Abductors, Lateral rotators, & Biceps, respectively
Lesion Localization?
Total Claw hand (Klumpke’s palsy)
Lower Trunk of Brachial Plexus (C8, T1)
- Loss of function of all lumbricals
- Compressed by cervical rib or by Pancoast tumor of the lung
Lesion Localization?
Wrist drop
Posterior Cord of Brachial Plexus OR Radial Nerve
Radial Nerve:
- compressed in axilla by incorrect use of crutch
- lesioned by midshaft fracture of humerus
- stretched by subluxation of radius
Winged scapula
Long Thoracic Nerve (C5, 6, 7)
Deltoid paralysis
Axillary Nerve
lesioned by:
- fracture of surgical neck
- dislocation of humerus
- intramuscular injections
Difficulty flexing elbow, variable sensory loss
Musculocutaneous Nerve
“Pope’s blessing”:
2nd & 3rd digits remain extended when asked to make a fist & thumb remains unopposed
Proximal Median Nerve lesion
compressed in:
- carpal tunnel syndrome
- dislocated lunate
“Claw hand” of pinky & ring finger when trying to open the hand
Ulnar Nerve lesion
- Loss of medial lumbricals function
- lesioned by trauma to heel of the hand; fracture of hook of hamate
Loss of sensation over the dorsum of the foot along w/ loss of dorsiflexion & eversion
Lesion to common perineal nerve:
Deep Peroneal Nerve = dorsiflexion
Superficial Peroneal = eversion & sensation to dorsum of foot
(Fibular neck fracture = common injury)
Loss of sensation over sole of the foot along w/ loss of plantar flexion & inversion of the foot
Tibial nerve
common injury = as it passes through the middle of the popliteal fossa
Loss of sensation on the medial aspect of the leg
Saphenous Nerve lesion (branch of femoral nerve)
Function of the intrinsic Lumbrical muscles of the hand?
- Flex MCP joints
- Extend DIP & PIP joints
“Claw hand” of index & middle finger when trying to open hand completely
Distal Median Nerve lesion
- Loss of lateral lumbrical function
"Ape Hand": Unopposable thumb (inability to abduct thumb)
Proximal median nerve lesion
(similar to “Pope’s Blessing”)
- Loss of Opponens Pollicis muscle function
Anterior Hip Dislocation – potential nerve damaged & symptoms?
Obturator Nerve (L2-4)
Motor Deficit = Thigh adduction
Sensory Deficit = Medial Thigh
Pelvic Fracture – potential nerve damaged & symptoms?
Femoral Nerve (L2-4)
Motor Deficit = Thigh flexion & leg extension
Sensory Deficit = Anterior thigh & medial leg
Trauma or compression of lateral aspect of leg – potential nerve damaged & symptoms?
Common Peroneal Nerve (L4-S2)
Motor Deficit = Foot eversion & dorsiflexion; Toe extension (foot drop, foot slap, steppage gait)
Sensory Deficit = Anterolateral leg & dorsal aspect of foot
Fibula neck fracture – potential nerve damaged & symptoms?
Common Peroneal Nerve (L4-S2)
Motor Deficit = Foot eversion & dorsiflexion; Toe extension (foot drop, foot slap, steppage gait)
Sensory Deficit = Anterolateral leg & dorsal aspect of foot
Posterior Hip Dislocation – potential nerve damaged & symptoms?
Superior Gluteal Nerve (L4-S1)
Motor Deficit = Thigh abduction (Trendelenburg Sign - contralateral hip drops when standing on leg ipsilateral to site of lesion)
Inferior Gluteal Nerve (L5-S2)
Motor Deficit = Can’t jump, climb stairs, or rise from seated position; can’t push inferiorly (downwards)
Polio – potential nerve damaged & symptoms?
Superior Gluteal Nerve (L4-S1)
Motor Deficit = Thigh abduction (Trendelenburg Sign - contralateral hip drops when standing on leg ipsilateral to site of lesion)
Sciatic nerve roots? What nerves does it become/split into?
L4-S3
Posterior thigh, splits into Common Peroneal & Tibial Nerve
(PED - Peroneal Everts & Dorsiflexes, if injured foot dropPED)
(TIP - Tibial Inverts & Plantarflexes, if injured can’t stand on TIP-toes)