NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense...
Transcript of NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense...
![Page 1: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/1.jpg)
NERVOUSSYSTEM:THEBRAIN
HumanAnatomyUnit4
![Page 2: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/2.jpg)
InAnatomyToday
![Page 3: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/3.jpg)
VentriclesoftheBrain
• Lateralventricles– 2ventriclesshapedlike“ramhorns”– Separatedbytheseptumpellucidum
• Thirdventricle– Surroundsthalamusdiencephalonandbrainstem
• Fourthventricle– Anteriortocerebellum– Contains3aperturesleadingtothe“subarachnoidspace”
v Cerebralaqueduct– Canalbetweenthirdandfourthventricle
![Page 4: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/4.jpg)
VentriclesoftheBrain
![Page 5: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/5.jpg)
CerebrospinalFluid(CNS)• Ventricleslinedwith
choroidplexus– Ependymalcells– Producecerebrospinalfluid
(CSF)– Produces500ml/day– 150mLincirculation
• SurroundsandbathesexposedsurfacesoftheCNS– Preventsfriction– Support– Regulationof
microenvironment
![Page 6: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/6.jpg)
CirculationofCSF
• CSFcirculatesthroughoutventricles,subarachnoidspaceandcentralcanal
• CSFisreturnedtogeneralcirculation– Arachnoidgranulations
– Projectintotheduralsinus
![Page 7: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/7.jpg)
CirculationofCSF
![Page 8: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/8.jpg)
TheCranialMeninges
![Page 9: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/9.jpg)
CranialMeningesDuraMater
• “Toughmother”– Denseirregularconnectivetissue
– Outermostmeninge• outer=periosteallayer• inner=meningeallayer
– “falxcerebri”
– 2layersformaspacebetweenwhicharetheduralsinuses
![Page 10: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/10.jpg)
CranialMeningesArachnoidandPiaMater
• “Spiderymother”• Arachnoidgranulations– forreturnofCSFtogeneralcirculation
• “Delicatemother”• Indissectablefromsurfaceofthebrain
• Looseconnectivetissue
![Page 11: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/11.jpg)
FalxCerebri
Falx cerebri is formed as an extension of the meningeal layer of the dura mater
![Page 12: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/12.jpg)
BloodVesselsoftheBrain
InternalcarotidarteriesVertebralarteries
JugularveinsDraintheduralsinuses
![Page 13: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/13.jpg)
MajorDivisionsoftheBrain
![Page 14: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/14.jpg)
Cerebrum• Cerebralhemispheres
– Leftandrighthalves– Separatedbylongitudinal
fissure– Connectedbytracts
• Dividedintofunctionallobes
• Contain“higherbraincenters”– Nucleiresponsibleformotor
coordinationandcontrolofmemory,emotionandotherfunctions
![Page 15: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/15.jpg)
CerebralCortex
• GrayMatter• Gyrus(gyrip.)– foldsofthecerebralsurface
• Sulcus(sulcip.)– groovesbetweengyri
• Fissure– deepgroove
![Page 16: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/16.jpg)
TheCerebralLobes
• 5majordivisionsineachhemisphere
• 4namedafterbonesunderwhichtheylie– Frontal– Parietal– Occipital– Temporal
• 1oninterior– Insula
![Page 17: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/17.jpg)
FrontalLobe• Amotorcortex• Pre-centralgyrusiswherethe
primarymotorcortexislocated– Controlsvoluntarymovements
• AlsomadeupofmostlyDopaminesensitiveneurons– Shorttermmemory– Reward– Learning– Emotions– Motivation
• Majormotorpathwayisthecorticospinaltract
![Page 18: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/18.jpg)
ParietalLobe
• SensoryCortex• Thepostcentralgyrusiswherethesomato-sensorycortexislocated– Involvedinintegratingsensoryinformation• Skin• Proprioception
• Languageprocessing
![Page 19: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/19.jpg)
OccipitalLobe
• Mapsmostlytotheoccipitalbone
• Isthevisualcortex– Receives,integratesandprocessesvisualinformation
– ClinicallyreferredtoasBrodmannarea17
![Page 20: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/20.jpg)
TemporalLobe
• Auditorycortex• Processesvisualinformationintomemories
• Languagecomprehension
• Emotionassociations• Declarative(long-term)memory– Factsandevents
![Page 21: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/21.jpg)
Insula
• Smalllobesdeepinlateralsulcusbeneathtemporallobes
• Involvedinconsciousness– Emotion,homeostasis,selfawareness,cognitivefunctioning
• Gustatorycortex
New study suggests that the insula is involved in smoking addiction…
![Page 22: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/22.jpg)
CerebralMedulla
• Myelinatedaxons=whitematter• ArrangedintotractsconnectingdifferentpartsoftheCNS
• Associationtracts– Connectregionsofcortexwithinsamehemisphere
• Commissuraltracts– Bridgesbetweencerebralhemispheres– Ex)corpuscallosum
• Projectiontracts– Betweencerebralcortex,caudalbrain,andspinalcord
![Page 23: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/23.jpg)
CerebralWhiteMatter
![Page 24: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/24.jpg)
BasalNuclei
• Paired,irregularmassesofgraymatter
• Connectedtocerebrum,thalamus,brainstem
• Involvedin– Motorprograms– Procedurallearning– Routinebehaviorsorhabits
– Eyemovements– Emotion
![Page 25: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/25.jpg)
LimbicSystem
• Largegroupofnucleithroughoutdifferentpartsofthebrain
• Responsibleforcontrolof– Emotion– Sexdrive– Aggression–Memoryconsolidation...amongotherfunctions
• Hippocampus– Responsibleformemoryconsolidation
![Page 26: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/26.jpg)
LimbicSystem
![Page 27: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/27.jpg)
Diencephalon
• “in-between” brain• Components– Epithalamus– Thalamus
• PairedR/L
– Hypothalamus
![Page 28: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/28.jpg)
Epithalamus• Connectsthelimbicsystemtootherpartsofthebrain
• Covers3rd ventricle• Posteriorportion– Pinealgland
• Melatonin• Circadianrhythms
– Habenularnucleus• Relaystationforlimbicsystem
• Visceralandemotionalresponsetoodors
![Page 29: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/29.jpg)
Thalamus
• Clustersofnucleiorganizedintogroups
• Majorrelaystationforsensoryinformation
• Graymatteronbothsidesofthirdventricle
![Page 30: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/30.jpg)
Hypothalamus
• Containsmanydiversenucleicontrolling– Bodytemperature– Sexdrive– Feeding– Drinking– Thirstsensation– Pituitarysecretions
• Formstheinferiorwallsofthethirdventricle
![Page 31: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/31.jpg)
BrainStem
• Connectsforebrain(cerebrum,diencephalon)andcerebellumtospinalcord
• 3parts– Midbrain– Pons– Medullaoblongata
![Page 32: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/32.jpg)
Midbrain
• CorporaQuadrigemina– Superiorcolliculus– Inferiorcolliculus
• Cerebralpeduncles• Nucleiinvolvedin:– vision,hearing– sleep/wakecycles– Alertness– Bodytemperatureregulation
– Motorprograms
![Page 33: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/33.jpg)
Pons• Containssensoryandmotor
tracts• Relaysignalsfromcerebrum
anddiencephalontothecerebellum
• Autonomicnuclei– Sleep,respiration,
swallowing,bladdercontrol,hearing,equilibrium,taste,eyemovement,facialexpressions,facialsensationandposture
– Playsaroleindreaming• Originforcranialnerves
V-VIII
![Page 34: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/34.jpg)
MedullaOblongata
• Theinferiormostregionofthebrainstem
• Autonomiccenters– Respiration,vomiting,sneezing,cardiovascularfunctions
• Medullarypyramidshousethepyramidaltracts– Decussationofthepyramids
• OrigincranialnervesIX-XII
![Page 35: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/35.jpg)
TheCerebellum• Secondlargestsingle
structureofthebrain• Threelobes• Arborvitae
– “thetreeoflife”– Whitematterofthe
cerebellum
• Folia• Involvedinmotorcontrolof
coordination,timingandprecisionofskeletalmuscleactivity
![Page 36: NERVOUS SYSTEM: THE BRAIN Anat 35... · Cranial Meninges Dura Mater •“Tough mother ” –Dense irregular connective tissue –Outermost meninge •outer = periosteal layer •inner](https://reader033.fdocuments.in/reader033/viewer/2022041919/5e6b1e1833fe5c5fb816028a/html5/thumbnails/36.jpg)
HistologyoftheCerebellum• Whitematter(medulla)
– Myelinatednervefibers
• Graymatter(cortex)– Granularlayer
• Granulecells– Smallestneuronsandmost
numerousneuronsinthebrain
– Purkinjelayer• Purkinjecells
– Processesformthedendritrictreeofthemolecularlayer
– >200synapses
– Molecularlayer• Dendritictree