brain and cranial nerves
TRANSCRIPT
Brain and Cranial Brain and Cranial NervesNerves
TerminologyTerminology
HemispheresHemispheres Gyrus (Gyri)Gyrus (Gyri) Sulcus (Sulci)Sulcus (Sulci) Longitudinal FissureLongitudinal Fissure VentriclesVentricles
– CSFCSF
Anatomy of the BrainAnatomy of the Brain
Cerebrum Cerebrum CerebellumCerebellum DiencephalonDiencephalon
– ThalamusThalamus– Hyothalamus Hyothalamus
Brain StemBrain Stem– MidbrainMidbrain– PonsPons– Medulla Medulla
oblongataoblongata
CerebrumCerebrum
AnatomyAnatomy– Frontal lobeFrontal lobe– Parietal lobeParietal lobe– Occipital lobeOccipital lobe– Precentral gyrusPrecentral gyrus– Postcentral gyrusPostcentral gyrus
FunctionsFunctions– Sensory cortexSensory cortex– Motor cortexMotor cortex– EmotionEmotion– Intellectual Intellectual
processesprocesses– AuditoryAuditory– VisualVisual– SpeechSpeech
CerebellumCerebellum
AnatomyAnatomy– HemispheresHemispheres
FunctionsFunctions– Compares Compares
intended intended movement with movement with what is actually what is actually happeninghappening
– Smooth, Smooth, coordinated coordinated movementsmovements
– Posture/balancePosture/balance
Brain StemBrain Stem
AnatomyAnatomy– Medulla Medulla
oblongataoblongata– PonsPons– MidbrainMidbrain
FunctionsFunctions– MedullaMedulla
Relays motor and Relays motor and sensory sensory informationinformation
Regulates Regulates heartbeat, heartbeat, breathing and breathing and blood vessel blood vessel dilationdilation
– PonsPons Control breathingControl breathing
Protective CoveringsProtective Coverings(Meninges)(Meninges) Dura materDura mater Dense connective tissueDense connective tissue
ArachnoidArachnoid Nonvascular connective tissueNonvascular connective tissue
Pia materPia mater Highly vascularHighly vascular
Covers surface of the brain and spinal cord Covers surface of the brain and spinal cord and invaginates along cortical surface to and invaginates along cortical surface to form perivascular spacesform perivascular spaces
Cerebral Spinal Fluid Cerebral Spinal Fluid
Formed in the choroid plexusFormed in the choroid plexus Reabsorbed into saggittal sinus Reabsorbed into saggittal sinus
by arachnoid villiby arachnoid villi Protects brain against concussive Protects brain against concussive
traumatrauma removes waste productsremoves waste products
Foramen of Monro
Cranial NervesCranial Nerves
I:I: OlfactoryOlfactory II:II: OpticOptic III:III: OculomotorOculomotor IV:IV: TrochlearTrochlear V:V: TrigeminalTrigeminal VI:VI: AbducensAbducens
VII: FacialVII: Facial VIII:VestibulocochlearVIII:Vestibulocochlear
– AcousticAcoustic IX:IX:
GlossopharyngealGlossopharyngeal X:X: VagusVagus XI:XI: AccessoryAccessory XII: HypoglossalXII: Hypoglossal
http://www.gwc.maricopa.edu/class/bio201/cn/cranial.htm
MnemonicMnemonic
OnOn OldOld Olympus’Olympus’ TowerTower TopTop AA
FinFin AndAnd GermanGerman ViewedViewed AA HopHop
MNEMONICMNEMONIC
OLFACTORYOLFACTORY OPTICOPTIC OCULOMOTOROCULOMOTOR TROCHLEARTROCHLEAR TRIGEMINALTRIGEMINAL ABDUCENSABDUCENS FACIALFACIAL VESTIBULOCOCHLEARVESTIBULOCOCHLEAR GLOSSOPHARYNGEALGLOSSOPHARYNGEAL VAGUSVAGUS ACCESSORYACCESSORY HYPOGLOSSALHYPOGLOSSAL
OHOH ONCEONCE ONEONE TAKESTAKES THE THE ANATOMYANATOMY FINALFINAL VERY VERY GOODGOOD VACATIONVACATION A-HEADA-HEAD
CN I: OLFACTORYCN I: OLFACTORY
Cranial nerve ICranial nerve I Function: Function:
– smellsmell Clinical test for Clinical test for
damage: damage: – determine determine
whether a person whether a person can smell can smell something something aromaticaromatic
CN II: OPTICCN II: OPTIC
Cranial nerve IICranial nerve II Function: Function:
– visionvision Clinical test for Clinical test for
damage: damage: – tests peripheral tests peripheral
vision and visual vision and visual acuityacuity
Effects of damage: Effects of damage: – blindness in part or blindness in part or
all of the visual fieldall of the visual field
CNIII: OCULOMOTORCNIII: OCULOMOTOR
Cranial nerve IIICranial nerve III Function: Function:
– eye movements, opening of eye movements, opening of eyelid, constriction of pupil, eyelid, constriction of pupil, focusing, proprioceptionfocusing, proprioception
Clinical tests for injury: Clinical tests for injury: – differences in pupil size; pupillary differences in pupil size; pupillary
response to light; eye trackingresponse to light; eye tracking Effects of damageEffects of damage
– dropping eyelid, dilated pupil, dropping eyelid, dilated pupil, double visiondouble vision
CNIV: TROCHLEARCNIV: TROCHLEAR
Cranial nerve IVCranial nerve IV Function: eye Function: eye
movements and movements and proprioceptionproprioception
Clinical test for injury: Clinical test for injury: ability to rotate eye ability to rotate eye inferolaterallyinferolaterally
Effects of damage – Effects of damage – double vision, patient double vision, patient tilts head toward affected tilts head toward affected sideside
CN V: TRIGEMINALCN V: TRIGEMINAL
Cranial nerve VCranial nerve V Function: sensory nerve of Function: sensory nerve of
the facethe face Clinical test for injury: Clinical test for injury:
– corneal reflex; sense of corneal reflex; sense of touch, pain, and touch, pain, and temperature; clench temperature; clench teeth; move mandible teeth; move mandible side to sideside to side
Effects of damage: Effects of damage: – loss of sensation and loss of sensation and
impaired chewingimpaired chewing
CN VI: ABDUCENS AND CN VI: ABDUCENS AND CN VII: FACIAL CN VII: FACIAL Cranial Nerve VICranial Nerve VI Function: Eye Function: Eye
movementsmovements Clinical test: lateral Clinical test: lateral
eye movementeye movement Effects of damage: Effects of damage:
inability to rotate eye inability to rotate eye laterally; at rest – eye laterally; at rest – eye rotates medially rotates medially because of action of because of action of antagonistic musclesantagonistic muscles
Cranial Nerve VIICranial Nerve VII Function: facial Function: facial
expression; sense of expression; sense of tastetaste
Clinical test: motor Clinical test: motor functions – close eyes, functions – close eyes, smile, whistle, frown, smile, whistle, frown, raise eyebrows; tasteraise eyebrows; taste
Effects of damage: Effects of damage: inability to control facial inability to control facial muscles; distorted muscles; distorted sense of tastesense of taste
CN VIII: CN VIII: VESTIBULOCOCHLEARVESTIBULOCOCHLEAR Cranial Nerve VIIICranial Nerve VIII Function: hearing and equilibriumFunction: hearing and equilibrium Clinical tests: test hearing, Clinical tests: test hearing,
balance, and ability to walk a balance, and ability to walk a straight linestraight line
Effects of damage: deafness, Effects of damage: deafness, dizziness, nausea, loss of balance, dizziness, nausea, loss of balance, and nystagmusand nystagmus
CN IX: CN IX: GLOSSOPHARANGEAL GLOSSOPHARANGEAL AND CN X: VAGUSAND CN X: VAGUS
Cranial Nerve IXCranial Nerve IX Function: swallowing, Function: swallowing,
salivation, gagging; salivation, gagging; touch, pressure, taste, touch, pressure, taste, and pain sensations and pain sensations from tongue, pharynx, from tongue, pharynx, and outer earand outer ear
Clinical tests: gag reflex, Clinical tests: gag reflex, swallowing, and swallowing, and coughingcoughing
Effects of damage: Effects of damage: difficulty swallowingdifficulty swallowing
Cranial Nerve XCranial Nerve X Function: swallowing; Function: swallowing;
taste; speech; taste; speech; respiratory, CV, and GI respiratory, CV, and GI regulation; sensations of regulation; sensations of hunger, fullness, and hunger, fullness, and intestinal discomfortintestinal discomfort
Clinical tests: test with Clinical tests: test with cranial nerve IXcranial nerve IX
Effects of damage: Effects of damage: hoarseness or loss of hoarseness or loss of voice; impaired voice; impaired swallowing and GI swallowing and GI motilitymotility
CN XI: ACCESSORY CN XI: ACCESSORY AND AND CN XII: HYPOGLOSSALCN XII: HYPOGLOSSAL Cranial Nerve XICranial Nerve XI
Function: swallowing; Function: swallowing; head, neck, and shoulder head, neck, and shoulder movementsmovements
Clinical tests: rotate head Clinical tests: rotate head and shrug shoulders and shrug shoulders against resistanceagainst resistance
Effects of damage: Effects of damage: impaired movement of impaired movement of head, neck, and head, neck, and shoulders; paralysis of shoulders; paralysis of sternocleidomastoidsternocleidomastoid
Cranial Nerve XIICranial Nerve XII Function: tongue Function: tongue
movements of speech, movements of speech, food manipulation, and food manipulation, and swallowingswallowing
Clinical test: tongue Clinical test: tongue functionfunction
Effects of damage: Effects of damage: difficulty in speech and difficulty in speech and swallowing; atrophy of swallowing; atrophy of tongue; inability to stick tongue; inability to stick out (protrude) tongueout (protrude) tongue