GROSS ANATOMY OF THE BRAIN & CRANIAL NERVES # 1 MARTINI, FUNDAMENTALS OF ANATOMY & PHYSIOLOGY, 9TH EDITION, CHAPTER # 14 3/22/2016 Exercise #20 Page # 249 1 NOTE: THIS IS A STUDY GUIDE, NOT AN ALL INCLUSIVE REVIEW. THERE MIGHT BE THINGS NOT COVERED BY THIS STUDY GUIDE THAT MIGHT BE ASKED IN YOUR PRACTICUMS / QUIZZES. STUDENTS ARE RESPONSIBLE FOR READING THEIR TEXBOOK (S) AND FOR ALL THE MATERIAL COVERED DURING THE LABORATORY PERIOD, AS PER THE COURSE SYLLABUS 3/22/2016 2 OBJECTIVES – – – 3/22/2016 Identifying the major regions of the brain and state their function. Identifying the meninges. Locating and naming selected cranial nerves. 3 CENTRAL NERVOUS SYSTEM (CNS)- BRAIN & SPINAL CORD PERIPFERAL NERVOUS SYSTEM (PNS)- NERVES & ASSOCITED GANGLIA CEREBRAL HEMIPHERES- 2 HALF OF THE CEREBEUM, RIGHT & LEFT DIVIDED BY LONGITUDINAL FISSURE GYRI (PLURAL)- THICK AREAS GYRUS- (SINGULAR)- FOLDS PRECENTRAL GYRUS POSTCENTRAL GYRUS FISSURES: DEEP GROOVES SULCI- SHALLOW GROOVES SEPARATING GYRI SULCY- PLURAL SULCUS- SINGULAR LONGITUDINAL FISSURE- IT SEPARATES THE RIGHT & LEFT HEMISPHERES CENTRAL SULCUS- IT DIVIDES THE CEREBRAL HEMISPHERS IN ANTERIOR & POSTERIOR LATERAL SULCUS- IT SEPARATES FRONTAL AND PARIETAL LOBES FROM TEMPORAL LOBE PARIETO OCCIPITAL SULCUS- IT SEPARATES THE PARIETAL LOBE FROM OCCIPITAL LOBE FRONTAL LOBE- FROM CENTRAL SULCUS ANTERIORLY PREFRONTAL CORTEX- MOST ANTERIOR PART OF THE FRONTAL LOBE F- CENTER OF THE INTELECT FOR RAZONALIZATION TEMPORAL LOBE- UNDER THE TEMPORAL BONES UNDER THE LATERAL SULCUS PARIETAL LOBE- UNDER THE PARIETAL BONES & BEHIND THE FRONTAL LOBE OCCIPITAL LOBE- POSTERIOR LOBE OF THE CEREBRUM UNDER OCCIPITAL BONE 3/22/2016 5 PRE CENTRAL GYRUS- GYRUS BEFORE THE CENTRAL SULCUS (ORANGE IN MODEL) IT CONTEINS THE PRIMARY MOTOR AREAF- TO CONTROL VOLUNTARY MUSCLE MOVEMENT POSTCENTRAL GYRUS- GYRUS AFTER THE CENTRAL SULCUS (LAVANDER IN MODEL) IT CONTEIS THE PRIMARY SOMATOSENSORY AREA F- TO RECEIVE SENSORY INFO FROM GENERAL SENSORY RECEPTORS EX- TOUCH, PAIN, TEMP SOMATOSENSORY ASSOCIATION AREABEHIND THE POST CENTRAL GYRUS (LAVANDER) F- TO INTERPRET SENSORY INFORMATION BROCA’S AREA- CONTEIS THE SPEECH CENTER F- TO CONTROL MUSCLES OF SPEECH 3/22/2016 6 3/22/2016 ALFONSO A. PINO. MD. 7 3/22/2016 ALFONSO A. PINO. MD. 8 3/22/2016 ALFONSO A. PINO. MD. 9 3/22/2016 ALFONSO A. PINO. MD. 10 3/22/2016 ALFONSO A. PINO. MD. 11 TURN THE MODEL OVER OLFACTORY BULBS- THE BULBS TO THE FRONT F- CARRY SENSORY INFO ABOUT SMELL OLFACTORY TRACS – WHERE THE BULB ARE ATTACHED TO F- TO CARRY SENSORY INFO ABOUT SMELL OPTIC CHIASMA- WHERE THE OPTIC NERVES CROSS (IN THE MIDDLE) OPTIC TRACTS- FROM OPTIC NERVES BACK TO THE BRAIN F- TO CARRY VISUAL INFORMATION PITUITARY GLAND (HYPOFISIS)F- TO PRODUCE MANY HORMONES MAMiILARY BODIES- (ORANGE & WHITE IN MODEL) F-TO CARRY SMELL IMPULSE 3/22/2016 12 3/22/2016 ALFONSO A. PINO. MD. 13 OPEN THE BRAIN IN HALF CEREBRAL PEDUNCLES- POSTERIOR PART OF THE PONS F- TO CARRY MOTOR INFORMATION PONS- CONNECTS THE CEREBRUM WITH THE CEREBELUM F-RELAYS SENSORY INFO TO CEREBELLUM & THALAMUS AND CONTAIN BREATHING CENTER SUBCONSCIOUS SOMATIC & VISCERAL MOTOR CENTERS MEDULA OBLONGATAF- RELAYS SENSORY INFO TO THALAMUS & BRAIN STEM TO CONTROL VITAL SIGNS (BLOOD PRESSURE, HEART RATE, RESPIRATORY RATE) 3/22/2016 14 3/22/2016 ALFONSO A. PINO. MD. 15 Corpora cuadrigemina2 superior colliculiesF- to process visual sensation for visual reflex To control reflex mov of eyes, head & neck 2 inferior colliculiesF- to process auditory sensation for auditory reflex To control reflex mov of head, neck, & trunk (loud voice) Corpus callosumF-to carry info between cerebral hemispheres Fornix- tracts of white matter that connects limbic system 3/22/2016 16 Septum pellucidum- it separates the lateral Ventricles (1 & 2) Thalamus- from anterior commisure to pineal gland F- relays & processing centers for sensory information Intermediate mass-(brown model); F- to connect both sides of the thalamus Hypothalamus- from superior to the optic chiasm to posterior margin of mammillary bodies F- to control emotions- feeding, hunger & thirst centers Autonomic f-heart rate, blood pressure, Respiration & digestive funct To secrete hormones (adh, oxytocine) To control circadian rhythms Epithalamus (pineal body- or gland)F- to produce melatonin h Setting circadian rhythm Timming human sexual maturation Protects brain against free radicals Location- lies posterior portion of roof of 3rd ventricle CerebellumVermis- (narrow band of cortex along the middline) F- to separate right & left cerebellar hemispheres arbor vitae- white mater of cerebellum Function of cerebellum- adjust postural movement balance and equilibrium Programming fine tuning movement to make movements smoo 3/22/2016 18 3/22/2016 ALFONSO A. PINO. MD. 19 3/22/2016 ALFONSO A. PINO. MD. 20 3/22/2016 ALFONSO A. PINO. MD. 21 3/22/2016 ALFONSO A. PINO. MD. 22 THE CEREBELLUM 3/22/2016 ALFONSO A. PINO. MD. 23 THE CEREBELLUM (ARBOR VITAE) 3/22/2016 24 MENINGES Meninx= membrane: for protection Cranial meninges (From exrternal to internal) Dura mater- endosteal layer Dural sinus Dura mater- meningeal layer Subdural space Arachnoid mater Subarcnoid space contains csf Pia mater- for nourishment cerebral cortex 3/22/2016 25 CRANIAL MENINGES (CONTINUATION) Dura mater Falx cerebri- formed by dura mater along longitudinal fissure F- to separate the cerebral hemispheres Superior sagital sinus- venous sinus within the falx cerebri Tentorium cerebelli- on top of the cerebellum F- to separate the cerebral hemispheres from those of the cerebellum 3/22/2016 26 3/22/2016 ALFONSO A. PINO. MD. 27 3/22/2016 ALFONSO A. PINO. MD. 28 VENTRICLES Function of the ventricles- to contain CSF Lateral ventricles (1 & 2) 3rd ventricle Interventricular foramen- to connect lateral ventricle with 3rd ventricle Cerebral aqueduct- to connect 3rd ventricle with fourth ventricle Fourth ventricle Choroid plexus- function- it contains the ependimal cells for production of CSF 3/22/2016 29 3/22/2016 ALFONSO A. PINO. MD. 30 3/22/2016 ALFONSO A. PINO. MD. 31 CRANIAL NERVES I- olfactory n- (not seen in charts, just in model) F- special sensory, to carry smell impulse II- optic n- special sensory, to carry visual info III- oculomotor-motor-to control movement of the muscles of the eyes IV-troclear-motor, eye movement (superior oblique muscles of the eyes V-trigeminal- (sensory & motor)- to face chewing muscles VI-abducens-motor- eye movement. Loc : pons & medulla F- lateral rectus muscle of the eyes VII- facial-(sensory & motor)F- muscles of facial expression Carries motor info for face 3/22/2016 ALFONSO A. PINO. MD. 33 VIII- vestibulococlear n- special sensory Vestibular branch- balance & equilibrium Cochlear branch- hearing IX- glosopharyngeal n- sensory & motorHead & neck X- vagus n- sensory & motorOrgans in thorax & abdomen XI-accessory n- motorNeck, upper back, trapezius & sternocleidomastoid muscles XII- hypoglossal n- motor- tongue movement 3/22/2016 34 OLFACTORY EPITHELIUM OLFACTORY FIBERS OLFACTORY BULB OLFACTORY TRACT (chapter #17) 3/22/2016 35 3/22/2016 ALFONSO A. PINO. MD. 36 3/22/2016 ALFONSO A. PINO. MD. 37 AUTONOMIC NERVOUS SYSTEM Parasympathetic or craniosacral divisionTo maintain body under resting conditions Preganglionic neuron: located in CNS, found in brain and sacral part of spinal cord (s2-s4) Pregaglionic fibers: from CNS to ganglia Intramural or terminal ganglion- contain ganglionic neurons postganglionic fibers: from ganglia to organ Sympathetic or thoraco lumbar divisionTo put the body in alert state Preganglionic neuron: in CNS (spinal cord t1-l2) White ramus communicans: contain preganglionic unmyelinatesd fibers Splanchnic nerves – preganglionic fibers Sympathetic chain ganglia: contain ganglionic neurons collateral ganglion: contain ganglionic neurons Gray ramus communicans: contain postganglionic unmylinated fibers REMEMBER! GO TO THE TUTORING ROO AND PRACTICE WITH MODELS. ROO 3326. 3/22/2016 39