sws42792's version from 2015-05-28 15:18

Sensory receptors

Question Answer
Free nerve endingsC fibers (slow, unmyelinated) and A delta fibers (fast, myelinated); found in all skin, some viscera; senses pain and temperature
Meissner corpusclesLarge, myelinated fibers, adapt quickly; found on glabrous (hairless) skin; senses fine/light touch, position sense
Pacinian corpusclesLarge, myelinated fibers, adapt quickly; found in deep skin layers, ligaments, joints; senses vibration, pressure
Merkel discsLarge myelinated fibers, adapt slowly; found in finger tips, superficial skin; sense pressure, deep static touch (shapes, edges), position sense
Ruffini corpusclesDendritic endings with capsule, adapt slowly; found in finger tips, joints; sense pressure, slippage of objects along surface of skin, joint angle change

Hypothalamic nuclei

Question Answer
VentromedialMediates satiety, destruction leads to hyperphagia, stimulated by leptin
LateralMediates hunger, destruction leads to anorexia, inhibited by leptin
AnteriorMediates heat dissipation (cooling) via parasympathetics, destruction leads to hyperthermia
PosteriorMediates heat conservation via sympathetics; destruction leads to hypothermia
ArcuateSecretion of dopamine (inhibits prolactin), GHRH and gonadatropin
ParaventricularADH, Corticotropin-releasing hormone, oxytocin, and THRH secretion
SupraopticSecretion of ADH and oxytocin
SuprachiasmaticCircadian rhythm regulation and pineal gland function (produces melatonin)

Sleep stages

Question Answer
Beta wavesAwake (eyes open) and REM sleep - highest frequency, lowest amplitude
Alpha wavesAwake (eyes closed)
Theta wavesStage N1 - light sleep
Sleed spindles and K complexesStage N2 - deeper sleep, when bruxism occurs
Delta wavesStage N3 - when sleepwalking, night terrors, and bedwetting occurs - lowest frequency, highest amplitude
Extraocular movements during REM due to...Activity of the PPRF (paramedian pontine reticular formation)
Bedwetting treatmentDesmopressin (ADH analog)

Thalamic nuclei (input, info, destination)

Question Answer
VPLSpinothalamic and dorsal columns/medial lemniscus; Pain, temperature, pressure, touch, vibration, proprioception; Primary somatosensory cortex
VPMTrigeminal and gustatory pathway; Face sensation, taste; Primary somatosensory cortex
LGNCN II; Vision; Calcarine sulcus
MGNSuperior olive and inferior colliculus of tectum; Hearing; Auditory cortex of temporal lobe
VLBasal ganglia, cerebellum; Motor; Motor cortex

Stroke Effects

Question Answer
MCAContralateral paralysis and sensory loss in upper limb and face, aphasia if on dominant side, hemineglect if nondominant
ACAContralateral paralysis and sensory loss in lower limb
Lenticulostriate arteryContalateral hemiparesis/hemiplegia (striatum, int. capsule), common location of lacunar infarcts due to HTN
ASAContralateral hemiparesis (upper and lower limbs), decreased contra proprioception, Ipsilateral hypoglossal dysfunction (tongue deviates ipsilaterally) - medial medullary syndrome
PICADysphagia, hoarseness, decreased gag reflex, ipsi Horner syndrome, decrease pain/temp ipsi face and contra body, vertigo, vomiting, nystagmus - Lateral medullary (Wallenberg) syndrome
AICAFacial paralysis (droop), decrease lacrimation and salivation, decrease taste ant. 2/3 of tongue, decrease pain/temp ipsi face and contra body, vomiting, vertigo, nystagmus
PCAContralateral hemianopia w/ macular sparing (occipital cortex)
Basilar arteryLocked-in syndrome!! preserved consciousness and blinking, quadriplegia, loss of facial. mouth and tongue movements
AComVisual field defects
PComCN III palsy - eye is "down and out" with ptosis and mydriasis

Ischemic stroke stages

Question Answer
12-48 hoursRed neurons
24-72 hoursNecrosis + neutrophils
3-5 daysMacrophages (microglia)
1-2 weeksReactive gliosis + vascular proliferation
>2 weeksGlial scar

Cranial Nerve and Vessel Passages

Question Answer
Cribriform plateCN I
Optic canalCN II, ophthalmic artery, central retinal vein
Superior orbital fissureCN III, IV, V1, VI, ophthalmic vein, sympathetic fibers
Foramen RotundumCN V2
Foramen OvaleCN V3
Foramen spinosumMiddle meningeal artery
Internal auditory meatusCN VII, VIII
Jugular foramenCN IX, X, XI, jugular vein
Hypoglossal canalCN XII
Foramen magnumspinal roots of CN XI, brain stem, vertebral arteries

Cranial Nerves

Question Answer
IOlfactory; smell (only CN without thalamic relay to cortex)
IIOptic; sight
IIIOcculomotor; eye movement (SR, IR, MR, IO), pupillary constriction (sphincter pupillae: Edinger-Westphal nucleus, muscarinic receptors), accomodation, eyelid opening (levator palpebrae)
IVTrochlear; eye movement (SO)
VTrigeminal; mastication, facial sensation (ophthalmic, maxillary, mandibular), somatosensation from anterior 2/3 tongue
VIAbducens; eye movement (LR)
VIIFacial; facial movement, taste anterior 2/3 tongue, lacrimation, salivation (submandibular and sublingual), eyelid closing (obicularis oculi), stapedius muscle in ear
VIIIVestibulocochlear; hearing, balance
IXGlossopharyngeal; taste and somatosensation from posterior 1/3 of tongue, swallowing, salivation (parotid), monitoring carotid body and sinus, and stylopharyngeus (elevates pharynx, larynx)
XVagus; taste from epiglottic region, swallowing, soft palate elevation, midline uvula, talking, coughing, thoracoabdominal viscera, monitoring aortic arch chemo- and baro receptors
XIAccessory; head turning, shoulder shrugging (SCM, trapezius)
XIIHypoglossal; tongue movement

Cranial nerve reflexes (afferent; efferent)

Question Answer
CornealV1 ophthalmic (nasociliary branch); VII (temporal branch: orbicularis oculi)
LacrimationV1 (loss of reflex does not preclude emotional tears); VII
Jaw jerkV3 (sensory - muscle spindle form masseter); V3 (motor - masseter)
PupillaryII; III
GagIX; X

Common cranial nerve lesions

Question Answer
CN V motor lesionJaw deviates toward side of lesion due to unopposed force from opposite pterygoid
CN X lesionUvula deviates away from side of lesion, weak side collapses and uvula points away
CN XI lesionWeakness turning head to contralateral side of lesion (SCM), shoulder droop on ipsilateral side of lesion (trapezius)
CN XII lesion (LMN)Tongue deviates toward side of lesion ("lick your wounds") due to weakened tongue muscles on affected side