CNSCNSCentral Nervous Central Nervous

SystemSystem

CNSCNSBrain and Spinal Brain and Spinal CordCord

CNS:CNS:PROTECTIONPROTECTION

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CNS:CNS:PROTECTIONPROTECTION

BONEBONE::Cranium = brainCranium = brainVertebrate = spineVertebrate = spine

CNS:CNS:PROTECTIONPROTECTION

MeningesMeninges: Fiborus : Fiborus tissuetissue

Color code a,b, b1,cColor code a,b, b1,c

CNS:CNS:PROTECTIONPROTECTION

Dura MaterDura Mater: : Toughest connective Toughest connective tissuetissue

Right under craniumRight under cranium

CNS:CNS:PROTECTIONPROTECTION

ArachnoidArachnoid: Spider-web : Spider-web covering under dura covering under dura mater.mater.

CNS:CNS:PROTECTIONPROTECTION

SubarachnoidSubarachnoid: Pockets : Pockets of the arachnoid that of the arachnoid that contain cerebral spinal contain cerebral spinal fluid (CSF)fluid (CSF)

CNS:CNS:PROTECTIONPROTECTION

Pia MaterPia Mater: Delicate, : Delicate, contains many blood contains many blood vessels.vessels.

CNS:CNS:PROTECTIONPROTECTION

CSFCSF: Circulates : Circulates subarachnoid spacesubarachnoid space

Cushions, and nourishes.Cushions, and nourishes.Surrounds entire CNSSurrounds entire CNS

Ohio State University: Neurology: Ohio State University: Neurology: College of Medicine. College of Medicine.

CSF from the lumbar region contains CSF from the lumbar region contains 15 to 45 15 to 45 mg/dl protein mg/dl protein (lower in childen) and (lower in childen) and 50-80 50-80 mg/dl glucosemg/dl glucose (two-thirds of blood glucose). (two-thirds of blood glucose). Protein concentration in cisternal and ventricular Protein concentration in cisternal and ventricular CSF is lower. Normal CSF contains CSF is lower. Normal CSF contains 0-5 0-5 mononuclear cellsmononuclear cells. The CSF pressure, . The CSF pressure, measured at lumbar puncture (LP), is 100-180 measured at lumbar puncture (LP), is 100-180 mm of H2O (8-15 mm Hg) with the patient lying mm of H2O (8-15 mm Hg) with the patient lying on the side and 200-300 mm with the patient on the side and 200-300 mm with the patient sitting up. sitting up.

ProblemsProblems

Increased protein:Increased protein: In bacterial meningitis, In bacterial meningitis, CSF protein may rise to 500 mg/dl. A more CSF protein may rise to 500 mg/dl. A more moderate increase (150-200 mg/dl) occurs moderate increase (150-200 mg/dl) occurs in inflammatory diseases of meninges in inflammatory diseases of meninges (meningitis, encephalitis), intracranial (meningitis, encephalitis), intracranial tumors, subarachnoid hemorrhage, and tumors, subarachnoid hemorrhage, and cerebral infarction. A more severe cerebral infarction. A more severe increase occurs in the Guillain-Barré increase occurs in the Guillain-Barré syndrome and acoustic and spinal syndrome and acoustic and spinal schwannoma. schwannoma.

ProblemProblem

Xanthochromia (blonde color)Xanthochromia (blonde color) of the of the CSF following subarachnoid hemorrhage CSF following subarachnoid hemorrhage is due to oxyhemoglobin which appears in is due to oxyhemoglobin which appears in 4 to 6 hours and bilirubin which appears in 4 to 6 hours and bilirubin which appears in two days. Xanthochromia may also be two days. Xanthochromia may also be seen with hemorrhagic infarcts, brain seen with hemorrhagic infarcts, brain tumors, and jaundice. tumors, and jaundice.

Normal Normal Clear as water Clear as water Abnormal findings Abnormal findings Faint yellow, orange or pink (Xanthochromia) Faint yellow, orange or pink (Xanthochromia)

CSF ProteinCSF Protein >100 mg/dl >100 mg/dl Red Blood Cell lysis Red Blood Cell lysis Red Blood Cell >100,000/mm3 (Subarachnoid Hemorrhage) Red Blood Cell >100,000/mm3 (Subarachnoid Hemorrhage)

Cloudy or turbid Cloudy or turbid CSF Leukocytes > 200 wbc/mm3 CSF Leukocytes > 200 wbc/mm3 Red Blood Cells > 400 per mm3 Red Blood Cells > 400 per mm3

Brown or Dark CSF Brown or Dark CSF Metastatic Melanoma (meningeal Melanomatosis) Metastatic Melanoma (meningeal Melanomatosis) Jaundice (Hyperbilirubinemia) Jaundice (Hyperbilirubinemia)

Green CSF Green CSF Hyperbilirubinemia Hyperbilirubinemia Purulent cerebrospinal fluid Purulent cerebrospinal fluid

(1) intervertebral (1) intervertebral discs, (2) vertebral discs, (2) vertebral bodies, (3) dura, (4) bodies, (3) dura, (4) epidural space, (5) epidural space, (5) spinal cord, and (6) spinal cord, and (6) subdural space subdural space

BRAINBRAIN

BRAINBRAINFolded to increase Folded to increase surface areasurface area

35 billion neurons (98%)35 billion neurons (98%)Adult = 3 lbsAdult = 3 lbs

BrainBrainBrain (3 lbs) at rest Brain (3 lbs) at rest needs as much needs as much oxygen as 61 lbs of oxygen as 61 lbs of skeletal muscle.skeletal muscle.

BrainBrain

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BRAINBRAINGyrus:Gyrus: Peaks of the Peaks of the folds, ridges.folds, ridges.

SulcusSulcus: furrow or : furrow or groove between gyrusgroove between gyrus

BrainBrainVentriclesVentricles: CSF circulate in : CSF circulate in

four major canals. (Travels four major canals. (Travels through brain and into spine) through brain and into spine) Continuous.Continuous.

Blue on page 228Blue on page 228

BRAINSTEMBRAINSTEM

BRAINSTEMBRAINSTEMLower brainLower brainUnconscious partUnconscious part

BRAINSTEMBRAINSTEMCOLOR CODE:COLOR CODE:Med. Oblongata = kMed. Oblongata = kPons = fPons = fMidbrain = aMidbrain = aReticular formation = gReticular formation = g

MEDULLA MEDULLA OBLONGATAOBLONGATA

BreathingBreathingHeart rateHeart rateReflex centerReflex center

PONSPONSConnects cerebellum Connects cerebellum to cerebrumto cerebrum

BreathingBreathing

MidbrainMidbrainLike a hookLike a hookDiencephalon to Diencephalon to cerebrumcerebrum

Eye reflexesEye reflexes

Reticular formationReticular formationFibers in the middle of Fibers in the middle of brainstem (connects to brainstem (connects to RAS)RAS)

Inactive so are you! Inactive so are you! Consciousness.Consciousness.

DiencephalonDiencephalon

COLORCOLORColor code the Color code the Diencephalon to the Diencephalon to the right.right.

Thalamus = aThalamus = aHypothalamus = bHypothalamus = b

DiencephalonDiencephalonOn top of On top of brainstembrainstem

ThalamusThalamusRelay station for Relay station for sensory headed to sensory headed to the cerebrum.the cerebrum.

Filters out messages.Filters out messages.

RASRASReticular Activation Reticular Activation SystemSystem

Deals with arousal Deals with arousal and consciousness.and consciousness.

HYPOTHALAMUSHYPOTHALAMUSMaintains homeostasis Maintains homeostasis (temp)(temp)

Emotions: Rage, Emotions: Rage, pleasure, pain, thirst, pleasure, pain, thirst, hungerhunger

COLOR CODE COLOR CODE On middle picture On middle picture page 10page 10

Cerebellum = hCerebellum = hArbor Vitae = iArbor Vitae = i

CEREBELLUMCEREBELLUMControls muscle balance Controls muscle balance and coordination.and coordination.

Lower, posterior part of Lower, posterior part of brain.brain.

Arbor VitaeArbor Vitae

White “tree-shaped” White “tree-shaped” structure inside structure inside cerebellum.cerebellum.

CerebrumCerebrumColor code Color code Frontal = a, a1, a2Frontal = a, a1, a2Parietal = b, b1Parietal = b, b1Temporal = c, c1Temporal = c, c1Occipital = d, d1Occipital = d, d1

CerebrumCerebrumOuter layer, largest Outer layer, largest region, called cortexregion, called cortex

About 1 inch thickAbout 1 inch thick4 lobes4 lobes

Frontal lobeFrontal lobeHigher level thinkingHigher level thinkingPersonality, speech Personality, speech center.center.

Parietal LobeParietal LobeSensory for touch and Sensory for touch and painpain

Temporal lobeTemporal lobeSensory for hearing Sensory for hearing and smelland smell

Occipital lobeOccipital lobe(back) Sensory for (back) Sensory for visionvision

Brain timeBrain time

Limbic systemLimbic systemArea around center Area around center of brain.of brain.

Not too much known Not too much known about area.about area.

Limbic systemLimbic systemEmotionEmotion: Emotional : Emotional states, fear, rage and states, fear, rage and sexual arousal.sexual arousal.

Limbic systemLimbic systemMemory and learning:Memory and learning:Long term memory and Long term memory and

retrieval (hippocampus) retrieval (hippocampus) (learning)(learning)

LateralizationLateralizationBrain divided laterally Brain divided laterally into 2 hemispheres.into 2 hemispheres.

Connected by corpus Connected by corpus callosumcallosum

LateralizationLateralizationRIGHT RIGHT music, art, music, art, creativecreative

Left Left math, verbal math, verbal