Slide 1Slide 2CerebellumSlide 4Slide 5Protection of the Central Nervous SystemSlide 7Slide 8MeningesSlide 10Cerebrospinal FluidVentricles and Location of the Cerebrospinal FluidSlide 13Blood Brain BarrierTraumatic Brain InjuriesCerebrovascular Accident (CVA)Alzheimer’s DiseaseSpinal CordSpinal Cord AnatomySlide 20Slide 21Slide 22Peripheral Nervous SystemStructure of a NerveClassification of NervesCranial NervesDistribution of Cranial NervesSlide 28Slide 29Slide 30CONTINUE: THE NERVOUS SYSTEM: 1. THE MENINGES 2. THE SPINAL CHORD 3. CRANIAL NERVESTwo hemispheres with convoluted surfacesProvides involuntary coordination of body movementsLET’s HAVE ANOTHER LOOK AT THE BRAIN: FIND STRUCTURES MENTIONED IN PREVIOUS LECTURES CAN YOU REMEMBER THEIR FUNCTION(S)?Figure 7.15aScalp and skinSkull and vertebral columnMeningesFigure 7.16aREMEMBER THE BRAIN HAS A CONSISTANCY OF …..JELLO SO TO PROTECT and CUSHION IT WE have a triple layer ofCerebrospinal fluidBlood brain barrierFigure 7.16aDura mater◦Double-layered external coveringPeriosteum – attached to surface of the skullMeningeal layer – outer covering of the brain◦Folds inward in several areasArachnoid layer◦Middle layer◦Web-likePia mater◦Internal layer◦Clings to the surface of the brainSimilar to blood plasma compositionFormed by the choroid plexusForms a watery cushion to protect the brainCirculated in arachnoid space, ventricles, and central canal of the spinal cordFigure 7.17a–bFigure 7.17cIncludes the least permeable capillaries of the bodyExcludes many potentially harmful substancesUseless against some substances◦Fats and fat soluble molecules◦Respiratory gases◦Alcohol◦Nicotine◦AnesthesiaConcussion◦Slight brain injury◦No permanent brain damageContusion◦Nervous tissue destruction occurs◦Nervous tissue does not regenerateCerebral edema◦Swelling from the inflammatory response◦May compress and kill brain tissueCommonly called a strokeThe result of a ruptured blood vessel supplying a region of the brainBrain tissue supplied with oxygen from that blood source diesLoss of some functions or death may resultProgressive degenerative brain diseaseMostly seen in the elderly, but may begin in middle ageStructural changes in the brain include abnormal protein deposits and twisted fibers within neuronsVictims experience memory loss, irritability, confusion and ultimately, hallucinations and deathExtends from the medulla oblongata to the region of T12Below T12 is the cauda equina (a collection of spinal nerves)Enlargements occur in the cervical and lumbar regionsFigure 7.18Exterior white mater – conduction tractsFigure 7.19Internal gray matter - mostly cell bodies◦Dorsal (posterior) horns◦Anterior (ventral) hornsFigure 7.19Central canal filled with cerebrospinal fluidFigure 7.19Meninges cover the spinal cordNerves leave at the level of each vertebrae◦Dorsal rootAssociated with the dorsal root ganglia – collections of cell bodies outside the central nervous system◦Ventral rootNerves and ganglia outside the central nervous systemNerve = bundle of neuron fibersNeuron fibers are bundled by connective tissueEndoneurium surrounds each fiberGroups of fibers are bound into fascicles by perineuriumFascicles are bound together by epineuriumFigure 7.20Mixed nerves – both sensory and motor fibersAfferent (sensory) nerves – carry impulses toward the CNSEfferent (motor) nerves – carry impulses away from the CNS12 pairs of nerves that mostly serve the head and neckNumbered in order, front to backMost are mixed nerves, but three are sensory onlyFigure 7.21 I Olfactory nerve – sensory for smellII Optic nerve – sensory for visionIII Oculomotor nerve – motor fibers to eye musclesIV Trochlear – motor fiber to eye musclesV Trigeminal nerve – sensory for the face; motor fibers to chewing musclesVI Abducens nerve – motor fibers to eye musclesVII Facial nerve – sensory for taste; motor fibers to the faceVIII Vestibulocochlear nerve – sensory for balance and hearingIX Glossopharyngeal nerve – sensory for taste; motor fibers to the pharynxX Vagus nerves – sensory and motor fibers for pharynx, larynx, and visceraXI Accessory nerve – motor fibers to neck and upper backXII Hypoglossal nerve – motor fibers to