1.Atlas ofNeuroanatomy andNeurophysiologySelections from the Netter Collection of Medical IllustrationsIllustrations by Frank H. Netter, MD John A. Craig, MDJames Perkins, MS, MFA Text byJohn T. Hansen, PhDBruce M. Koeppen, MD, PhD

2. Atlas of Neuroanatomy and NeurophysiologySelections from the Netter Collection of Medical IllustrationsCopyright 2002 Icon Custom Communications. All rights reserved.The contents of this book may not be reproduced in any form without writtenauthorization from Icon Custom Communications. Requests for permissionshould be addressed to Permissions Department, Icon Custom Communications,295 North St., Teterboro NJ 07608, or can be made at www. Netterart.com.NOTICEEvery effort has been taken to confirm the accuracy of the information presented.Neither the publisher nor the authors can be held responsible for errors or for anyconsequences arising from the use of the information contained herein, and makeno warranty, expressed or implied, with respect to the contents of the publication.Printed in U.S.A. 3. ForewordFrank Netter: The Physician, The Artist, The ArtThis selection of the art of Dr. Frank H. Netter on neuroanatomy and neurophysiology is drawnfrom the Atlas of Human Anatomy and Netters Atlas of Human Physiology. Viewing these picturesagain prompts reflection on Dr. Netters work and his roles as physician and artist.Frank H. Netter was born in 1906 in New York City. He pursued his artistic muse at the Sorbonne,the Art Students League, and the National Academy of Design before entering medical school atNew York University, where he received his M.D. degree in 1931. During his student years, Dr.Netters notebook sketches attracted the attention of the medical faculty and other physicians, allow-ing him to augment his income by illustrating articles and textbooks. He continued illustrating as asideline after establishing a surgical practice in 1933, but ultimately opted to give up his practice infavor of a full-time commitment to art. After service in the United States Army during the SecondWorld War, Dr. Netter began his long collaboration with the CIBA Pharmaceutical Company (nowNovartis Pharmaceuticals). This 45-year partnership resulted in the production of the extraordinarycollection of medical art so familiar to physicians and other medical professionals worldwide.When Dr. Netters work is discussed, attention is focused primarily on Netter the artist and onlysecondarily on Netter the physician. As a student of Dr. Netters work for more than forty years, I cansay that the true strength of a Netter illustration was always established well before brush was laid topaper. In that respect each plate is more of an intellectual than an artistic or aesthetic exercise. It iseasy to appreciate the aesthetic qualities of Dr. Netters work, but to overlook its intellectual quali-ties is to miss the real strength and intent of the art. This intellectual process requires thorough under-standing of the topic, as Dr. Netter wrote: Strange as it may seem, the hardest part of making a med-ical picture is not the drawing at all. It is the planning, the conception, the determination of point ofview and the approach which will best clarify the subject which takes the most effort.Years before the inception of the integrated curriculum, Netter the physician realized that agood medical illustration can include clinical information and physiologic functions as well as anato-my. In pursuit of this principle Dr. Netter often integrates pertinent basic and clinical science ele-ments in his anatomic interpretations. Although he was chided for this heresy by a prominentEuropean anatomy professor, many generations of students training to be physicians rather thananatomists have appreciated Dr. Netters concept.The integration of physiology and clinical medicine with anatomy has led Dr. Netter to another,more subtle, choice in his art. Many texts and atlases published during the period of Dr. Netterscareer depict anatomy clearly based on cadaver specimens with renderings of shrunken and shriv-eled tissues and organs. Netter the physician chose to render live versions of these structuresnotshriveled, colorless, formaldehyde-soaked tissues, but plump, robust organs, glowing with color!The value of Dr. Netters approach is clearly demonstrated by the plates in this selection.John A. Craig, MDAustin, Texas 4. This volume brings together two distinct but related aspects of the work of FrankH. Netter, MD, and associated artists. Netter is best known as the creator of theAtlas of Human Anatomy, a comprehensive textbook of gross anatomy that hasbecome the standard atlas for students of the subject. But Netters work includedfar more than anatomical art. In the pages of Clinical Symposia, a series of mono-graphs published over a period of more than 50 years, and in The Netter Collectionof Medical Illustrations, this premier medical artist created superb illustrations ofbiological and physiological processes, disease pathology, clinical presentations,and medical procedures.As a service to the medical community, Novartis Pharmaceuticals has commis-sioned this special edition of Netters work, which includes his beautiful andinstructive illustrations of nervous system anatomy as well as his depictions ofneurophysiological concepts and functions. We hope that readers will find Dr.Netters renderings of neurological form and function interesting and useful. 5. Click any title below to link to that plate.Part 1 NeuroanatomyCerebrumMedial Views . . . . . . . . . . . . . . . . . 2 Oculomotor (III), Trochlear (IV) and Abducent (VI) Nerves: Schema. . . . . . . 27CerebrumInferior View. . . . . . . . . . . . . . . . . . 3Trigeminal Nerve (V): Schema . . . . . . . . . . . . 28Basal Nuclei (Ganglia). . . . . . . . . . . . . . . . . . . . 4Facial Nerve (VII): Schema . . . . . . . . . . . . . . . 29Thalamus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Vestibulocochlear Nerve (VIII): Schema. . . . . 30Cerebellum . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Glossopharyngeal Nerve (IX): Schema . . . . . . 31Brainstem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Vagus Nerve (X): Schema . . . . . . . . . . . . . . . . 32Fourth Ventricle and Cerebellum . . . . . . . . . . . 8Accessory Nerve (XI): Schema . . . . . . . . . . . . 33Accessory Nerve (XI) . . . . . . . . . . . . . . . . . . . . 9Hypoglossal Nerve (XII): Schema . . . . . . . . . . 34Arteries to Brain and Meninges . . . . . . . . . . . 10Nerves of Heart . . . . . . . . . . . . . . . . . . . . . . . . 35Arteries to Brain: Schema . . . . . . . . . . . . . . . . 11Autonomic NervesArteries of Brain: Inferior Views . . . . . . . . . . . 12 and Ganglia of Abdomen. . . . . . . . . . . . . . . 36Cerebral Arterial Circle (Willis) . . . . . . . . . . . 13Nerves of Stomach and Duodenum . . . . . . . . 37Arteries of Brain: Frontal View and Section . . 14Nerves of StomachArteries of Brain: and Duodenum (continued) . . . . . . . . . . . . 38 Lateral and Medial Views . . . . . . . . . . . . . . . 15Nerves of Small Intestine . . . . . . . . . . . . . . . . 39Arteries of Posterior Cranial Fossa . . . . . . . . . 16Nerves of Large Intestine . . . . . . . . . . . . . . . . 40Veins of Posterior Cranial Fossa . . . . . . . . . . . 17 Nerves of Kidneys,Deep Veins of Brain. . . . . . . . . . . . . . . . . . . . . 18Ureters and Urinary Bladder . . . . . . . . . . . . 41Subependymal Veins of Brain . . . . . . . . . . . . . 19Nerves of Pelvic Viscera: Male . . . . . . . . . . . . 42Hypothalamus and Hypophysis . . . . . . . . . . . 20Nerves of Pelvic Viscera: Female . . . . . . . . . . 43Arteries and VeinsMedian Nerve . . . . . . . . . . . . . . . . . . . . . . . . . 44 of Hypothalamus and Hypophysis . . . . . . . . 21Ulnar Nerve . . . . . . . . . . . . . . . . . . . . . . . . . . . 45Relation of Spinal Nerve Roots to Vertebrae . . . 22Radial Nerve in ArmAutonomic Nervous System:and Nerves of Posterior Shoulder . . . . . . . . 46 General Topography. . . . . . . . . . . . . . . . . . . 23 Radial Nerve in Forearm . . . . . . . . . . . . . . . . . 47Spinal Nerve Origin: Cross Sections. . . . . . . . 24 Sciatic Nerve and PosteriorOlfactory Nerve (I): Schema . . . . . . . . . . . . . . 25Cutaneous Nerve of Thigh . . . . . . . . . . . . . . 48Optic Nerve (II)Tibial Nerve . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 (Visual Pathway): Schema . . . . . . . . . . . . . . 26Common Fibular (Peroneal) Nerve. . . . . . . . . 50 6. NEUROANATOMY Cerebrum: Medial Views Sagittal section ofCingulate gyrus Paracentral sulcus brain in situCentral sulcus (Rolando) Cingulate sulcusParacentral lobuleMedial frontal gyrusMarginal sulcusSulcus of corpus callosum Corpus callosumFornix Precuneus Septum pellucidumSuperior sagittal sinusInterventricular Choroid plexusforamen (Monro)of 3rd ventricle InterthalamicStria medullaris adhesion of thalamusThalamus and Parietooccipital3rd ventriclesulcus SubcallosalCuneus (parolfactory)Habenular areacommissureAnterior Pineal bodycommissure PosteriorSubcallosalcommissuregyrusCalcarine sulcusHypothalamicsulcusStraight sinusin tentoriumLaminacerebelliterminalisGreat cerebral veinSupra-(Galen)opticrecess Superior colliculusOptic chiasmInferior colliculus Tectal (quadrigeminal) plate Tuber cinereumCerebellumHypophysis (pituitary gland)Superior medullary velum Mammillary body 4th ventricle and choroid plexusCerebral peduncle Inferior medullary velum Pons Cerebral aqueduct Medulla oblongata(Sylvius)Medial surface of cerebralGenuhemisphere: brainstem excised Rostrum ofTrunk corpus callosumSpleniumCingulate gyrusMammillothalamicIsthmus of cingulate gyrusfasciculus Parietooccipital sulcus Mammillary bodyCuneusUncusCalcarine sulcusOptic nerve (II) Lingual gyrus Olfactory tract Collateral sulcusCrusBodyof fornix Rhinal sulcusColumnMedial occipitotemporal gyrusFimbria of hippocampusOccipitotemporal sulcus Dentate gyrusLateral occipitotemporal gyrus Parahippocampal gyrus2 7. Cerebrum: Inferior ViewNEUROANATOMYSectioned brainstemFrontal pole of cerebrumLongitudinal cerebral fissure Straight gyrus Genu of corpus callosumOlfactory sulcusLamina terminalis Orbital sulci Olfactory bulb Orbital gyri Olfactory tract Optic chiasm Temporal poleOptic nerve (II) (cut)Lateral sulcus (Sylvius)Hypophysis Inferior temporal sulcus (pituitary gland)Inferior temporal gyrus Anteriorperforated substanceOptic tractTuber cinereumInferior (infero-Mammillary bodylateral) marginof cerebrum Posterior perforatedsubstance (ininterpeduncularRhinal sulcus fossa)Cerebral crusUncus Lateral geniculate bodyInferiortemporal gyrus Substantia nigraMedial geniculateOccipitotemporalbodysulcus Red nucleus Lateral occipito- temporal gyrus Pulvinar of thalamusSuperior colliculus (of Collateral sulcuscorpora quadrigemina)Cerebral aqueductParahippocampal gyrusSplenium of corpus callosum Medial occipitotemporal gyrusApex of cuneus Calcarine sulcus Occipital pole of cerebrum Longitudinal cerebral fissureIsthmus of cingulate gyrus 3 8. NEUROANATOMYBasal Nuclei (Ganglia)Horizontal sectionsthrough cerebrumA B Genu of corpus callosumHead of caudate nucleus Lateral ventricle Anterior limb of internal GenucapsuleSeptum pellucidum Posterior limbColumn of fornix Putamen Lentiform Globus pallidus nucleusInsula(island of Reil) 3rd ventricleInterthalamicadhesionExternal capsule ThalamusClaustrumCrus of fornixRetrolenticular partof internal capsuleChoroid plexusof lateral ventricle Tail of caudate nucleus Splenium of Hippocampus and fimbria corpus callosumOccipital (posterior) hornof lateral ventricleHabenula Organization of basal nuclei (ganglia) APineal bodyBCaudate Putamen Globusnucleus pallidusCleft for internal capsule Lentiform Striatumnucleus CaudateBody nucleusHead ThalamusCorpusstriatumLevels of AAsectionsabove BBBasal nuclei(ganglia)Pulvinar Lentiform nucleusMedial geniculate body (globus pallidus medial to putamen)Lateral geniculate bodyAmygdaloid bodyTail of caudate nucleusInterrelationship of thalamus, lentiform nucleus, caudatenucleus and amygdaloid body (schema): left lateral view4 9. Thalamus NEUROANATOMY Interventricular foramen (Monro) Corpus callosum (cut) Tela choroidea (cut edge)Head of caudate nucleus of 3rd ventricleSeptum pellucidum3rd ventricleColumns of fornixChoroid plexusAnterior tubercleSuperior thalamostriate veinStria terminalis Pes hippocampiTemporal (inferior) horn Interthalamic adhesionof lateral ventricle Lamina affixa Internal cerebral veinStria medullarisDentate gyrus Habenular trigone Collateral eminence Pulvinar (retracted)Hippocampus Lateral geniculate body Fimbria of hippocampusPosterior commissure Medial geniculate body Habenular commissure Brachium of superior colliculus Pineal bodyBrachium of inferior colliculusCollateral trigoneSuperior colliculusCalcar avis Inferior colliculusOccipital (posterior) hornCerebellumof lateral ventricle Calcarine sulcusInternal3rd ventriclemedullaryInterthalamiclamina adhesionPulvinarrrio a nte in dia An mMe ial Ladna MDIntralaminar Me llar y lami VA LPnuclei eduL Drn al m Inte LP VL M3rd ventricleVPL VP Reticular nucleusVI CMMVP ML VP VP Thalamic nucleiPulvinarExternalLateral geniculate bodymedullaryCMCentromedianlaminaMedial geniculate body LDLateral dorsal LPLateral posterior Median nuclei M Medial Schematic representation of thalamus MDMedial dorsal(external medullary lamina and Schematic section VAVentral anterior reticular nuclei removed) through thalamusVIVentral intermedial (at level of broken VLVentral lateralLateral nuclei line shown in figureVPVentral posterior at right)Medial nuclei VPL Ventral posterolateral VPM Ventral posteromedialAnterior nuclei5 10. NEUROANATOMY CerebellumSuperior surface Anterior cerebellar notchAnterior lobeQuadrangular lobule (H IV-V)Central lobule (II & III)Primary fissureHorizontal fissureCulmen (IV & V)Simple lobule (H VI)SuperiorvermisDeclive (VI)Posterior lobePostlunate fissureFolium (VII A)Superior semilunar(anseriform) lobule (H VII A)Horizontal fissure Inferior semilunarPosterior cerebellar notch (caudal) lobule (H VII B) Central lobule Anterior lobe Inferior surfaceSuperior vermis Wing of central lobule Lingula (I)Superior Superior medullary velum MiddleCerebellar pedunclesInferiorFlocculus (H X)Flocculonodular lobe4th ventriclePosterolateral (dorsolateral)Inferior medullary velumfissure Nodule (X) Retrotonsillar fissure Uvula (IX)Posterior lobeInferiorvermis Tonsil Pyramid (VIII)Biventer lobule (H VIII) Tuber (VII B) Secondary (postpyramidal) fissurePosterior cerebellar notch Horizontal fissure Inferior semilunar (caudal) lobule (H VII B)Cerebral crusDecussation ofsuperior cerebellar pedunclesMedial longitudinal fasciculus 4th ventricleNuclear layer ofSuperior medullary velummedulla oblongataFastigial Superior cerebellarpeduncleGloboseCerebellarnuclei Lingula (I)Dentate VermisEmboliform Section in plane of superior cerebellar peduncle6 11. BrainstemNEUROANATOMY Posterolateral view Thalamus (cut surface) Lateral geniculate body Pulvinars of thalamiOptic tractPineal bodyMedial geniculate body Superior colliculi Brachia of superior and inferior colliculi Inferior colliculi Cerebral crusTrochlear nerve (IV)PonsSuperior medullary velumTrigeminal nerve (V) Superior cerebellar peduncleMiddle cerebellar peduncle Rhomboid fossa of 4th ventricleVestibulocochlear nerve (VIII) Glossopharyngeal (IX) andFacial nerve (VII) vagus (X) nerves Inferior cerebellar peduncleCuneate tubercle Hypoglossal nerve (XII)Gracile tubercle Accessory nerve (XI) Dorsal roots of 1st spinal nerve (C1) Cuneate fasciculusGracile fasciculusOlfactory tractAnterior view Anterior perforated substanceInfundibulum (pituitary stalk)Optic chiasmMammillary bodiesOptic tract Temporal lobe (cut surface)Oculomotor nerve (III)Tuber cinereumTrochlear nerve (IV)Cerebral crus Trigeminal nerve (V) Lateral geniculate bodyAbducent nerve (VI)Facial nerve (VII) andPosterior perforated substanceintermediate nerveVestibulocochlear nerve (VIII)PonsFlocculus of cerebellumMiddle cerebellar peduncleChoroid plexus of 4thventricleOliveGlossopharyngeal nerve (IX) PyramidVagus nerve (X)Ventral roots of 1st spinal nerve (C1)Hypoglossal nerve (XII) Accessory nerve (XI) Decussation of pyramids 7 12. NEUROANATOMYFourth Ventricle and CerebellumPosterior view Habenular trigone Medial Geniculate bodies3rd ventricleLateralPulvinar of thalamusDorsal median sulcusPineal bodySuperior cerebellar peduncleSuperior colliculus Locus ceruleusInferior colliculusMedial eminence Trochlear nerve (IV)Facial colliculusVestibular area Superior medullary velum Dentate nucleus Superior of cerebellumCerebellar peduncles Middle InferiorStriae medullares Lateral recessTenia of 4th ventricle Superior fovea Cuneate tubercle Sulcus limitansGracile tubercleInferior foveaDorsal median sulcus Trigeminal tubercle Lateral funiculusHypoglossal trigone Cuneate fasciculusVagal trigoneGracile fasciculus ObexInterthalamic adhesion Median sagittal sectionPosterior commissure Body of fornix Habenular commissureThalamus (in3rd ventricle) Pineal bodyInterventricularSplenium of corpus callosumforamen (Monro) Great cerebral vein (Galen)Anterior commissure Lamina terminalisLingula (I)Hypothalamic sulcus Central lobule (II-III) Vermis of Cerebral peduncleCulmen (IV-V)cerebellumCerebral aqueduct (Sylvius) Declive (VI)Superior colliculus Folium (VII A)Tectal (quadrigeminal) plate Superior medullary velumInferior colliculusPonsInferior medullary velumMedial longitudinal fasciculus Tuber (VII B) 4th ventricle Pyramid (VIII) Vermis of Choroid plexus of 4th ventriclecerebellum Uvula (IX)Medulla oblongata Nodulus (X) Median aperture (foramen of Magendie)Decussation of pyramidsChoroid plexus of 4th ventricle Central canal of spinal cordTonsil of cerebellum8 13. Accessory Nerve (XI): SchemaNEUROANATOMYNucleus ambiguusCranial root of accessory nerve (joins vagus nerveand via recurrent laryngeal nerve supplies muscles ofVagus nerve (X) larynx, except cricothyroid)*Spinal root ofaccessory nerve Jugular foramenForamenmagnumSuperior ganglionof vagus nerveAccessory nerve (XI)*Inferior ganglionof vagus nerveC1 spinal nerve C2 spinal nerveAccessory nerve(to sternocleidomastoidand trapezius muscles)Sternocleidomastoid muscle (cut)C3 spinal nerve C4 spinal nerveTrapezius muscle Efferent fibers Proprioceptive fibers*Recent evidence suggests that the accessory nerve lacks a cranial root and has no connection to the vagus nerve.Verification of this finding awaits further investigation. 9 14. NEUROANATOMY Arteries to Brain and MeningesLeft middle meningeal artery Middle cerebral arteryPosterior cerebral arteryAnterior cerebral artery Superior cerebellar arteryAnterior communicating artery Basilar arteryOphthalmic artery Left labyrinthine (internal acoustic) artery Posteriorcommunicating Mastoid branch ofartery left occipital arteryCavernous sinus Anterior inferior cerebellar arteryMiddlemeningeal Posterior meningealartery branch of left ascending pharyngeal artery Posterior inferior cerebellar artery Left and rightMaxillary vertebral arteriesartery (intracranial part)Superficial Posterior meningealtemporal branch of vertebralartery artery ExternalAnterior meningeal carotidbranch of vertebral artery artery Posterior auricular arteryFacial artery Occipital artery Lingual artery Internal carotid arteryAscending pharyngeal artery Carotid sinus Superior laryngeal arteryCarotid body Superior thyroid artery Vertebral artery (cervical part)Common carotid arteryTransverse process of C6 Ascending cervical artery (cut)Deep cervical artery Inferior thyroid artery Supreme intercostal artery Thyrocervical trunk Costocervical trunk Brachiocephalic trunkSubclavian arteryInternal thoracic artery10 15. Arteries to Brain: Schema NEUROANATOMYAnterior cerebral artery Anterior communicating artery 1Middle cerebral artery Ophthalmic artery Supraorbital artery Posterior communicating arterySupratrochlear arteryCaroticotympanic branch233Lacrimal arteryof internal carotid artery 3 1 Dorsal nasal arteryPosterior cerebral arteryMiddle meningeal arterySuperior cerebellar artery3Angular artery Anterior tympanic artery 1 Superficial temporal artery Middle meningeal artery 1 Posterior auricular artery 4 Maxillary artery Facial artery 5 5Occipital artery Basilar artery 4Lingual artery Anterior inferior cerebellar artery 5 5Ascending pharyngeal arteryPosterior inferior 5 Anterior spinal arterycerebellar artery Spinal segmental medullary branches External carotid artery 5 Vertebral arteryInternal carotid artery5Common carotid artery Superior thyroid arteryDeep cervical artery 5Common carotid arteryTransverse cervical arterySuprascapular artery Vertebral artery Supreme intercostal artery Ascending cervical artery Costocervical trunkInferior thyroid arteryThyrocervical trunk Subclavian artery Subclavian arteryInternal thoracic arteryBrachiocephalic trunkAnastomosesArch 1RightLeftAorta Descending 2CarotidVertebralAscending3Internal carotidExternal carotid 4SubclavianCarotid 5SubclavianVertebral11 16. NEUROANATOMYArteries of Brain: Inferior Views Medial frontobasal (orbitofrontal) arteryAnterior communicating arteryAnterior cerebral arteryDistal medial striate artery(recurrent artery of Heubner) Internal carotid artery Anterolateral central (lenticulostriate) arteriesMiddle cerebral arteryLateral frontobasal (orbitofrontal) arteryPrefrontal artery Anterior choroidal artery Posterior communicating artery Posterior cerebral arterySuperior cerebellar artery Basilar artery Pontine arteries Labyrinthine (internal acoustic) arteryAnterior inferior cerebellar arteryVertebral artery Anterior spinal arteryPosterior inferior cerebellar artery (PICA) (cut) Posterior spinal artery Cerebral arterial circle (Willis) Distal medial striate artery(broken line) (recurrent artery of Heubner) Anterior communicating arteryAnterior cerebral artery Middle cerebral arteryPosterior communicating arteryAnterior choroidal artery Optic tract Posterior cerebral arteryCerebral crus Lateral geniculate bodyPosterior medial choroidal artery Posterior lateral choroidal artery Choroid plexus of lateral ventricleMedial geniculate bodyPulvinar of thalamus Lateral ventricle12 17. Cerebral Arterial Circle (Willis)NEUROANATOMYDistal medial striate arteryVessels dissected out: inferior view(recurrent artery of Heubner) Anterior cerebral artery Anteromedial central (perforating)(A2 segment)arteriesAnterior communicating artery Hypothalamic artery Anterior cerebral artery(A1 segment) Anterolateral centralOphthalmic artery(lenticulostriate) arteriesInternal carotid arteryMiddle cerebral arterySuperior hypophyseal arteryPosterior communicating artery Inferior hypophyseal artery Anterior choroidal arteryPosterior cerebral artery (P2 segment) Thalamotuberal (P1 segment) (premammillary) arteryPosteromedial centralSuperior cerebellar artery(perforating) arteries Basilar arteryThalamoperforating arteryPontine arteriesPosteromedial central(paramedian) arteriesAnterior inferior cerebellar artery Labyrinthine (internal acoustic) artery Vertebral arteryVessels in situ: inferior viewAnterior cerebral artery Anterior communicating artery Optic chiasmHypothalamic artery Cavernous sinus Internal carotid artery Infundibulum (pituitary stalk) Superior hypophyseal artery and long hypophyseal portal veins Adenohypophysis (anterior Middle cerebral arterylobe of pituitary gland) Inferior hypophyseal arteryNeurohypophysis (posteriorlobe of pituitary gland)Posterior communicating artery Posteromedial central (perforating) arteriesEfferent hypophyseal veins Superior cerebellar artery Posterior cerebral arteryBasilar artery 13 18. NEUROANATOMYArteries of Brain: Frontal View and SectionCorpus callosum Paracentral artery Medial frontal branches Anterolateral central (lenticulostriate) arteries Pericallosal artery Lateral frontobasal Callosomarginal artery (orbitofrontal) arteryPolar frontal arteryPrefrontal arteryAnterior cerebralPrecentral (pre-rolandic) arteriesand central (rolandic)sulcal arteriesMedial frontobasal (orbitofrontal) arteryAnterior parietal(postcentral sulcal)Distal medial striatearteryartery (recurrentartery of Heubner)Posterior parietalInternal carotidarteryartery Branch to Anterior choroidal angular gyrus arteryTemporal branchesPosterior cerebral(anterior, middlearteryand posterior)Superior cerebellar artery Middle cerebral artery and branchesBasilar and pontine arteries (deep in lateral cerebral [sylvian] sulcus) Labyrinthine (internal acoustic) artery Anterior communicating arteryVertebral artery Posterior communicating arteryPosterior inferior cerebellar arteryAnterior inferior cerebellar artery Anterior spinal arteryPosterior spinal arteryFalx cerebriCallosomarginal arteries Corpus striatumand (caudate and lentiform nuclei) Pericallosal arteries(branches of anteriorAnterolateral central cerebral arteries)(lenticulostriate) arteries Insula (island of Reil)Trunk of corpus callosum Limen of insulaInternal capsule Precentral (pre-rolandic), central (rolandic) sulcalSeptum pellucidum and parietal arteriesRostrum of corpus callosum Lateral cerebral (sylvian) sulcusAnterior cerebral arteries Temporal branches of middle cerebral arteryDistal medial striate artery(recurrent artery of Heubner) Temporal lobeAnterior communicating artery Middle cerebral arteryOptic chiasmInternal carotid artery14 19. Arteries of Brain: Lateral and Medial Views NEUROANATOMY Anterior parietal (postcentral sulcal) artery Posterior parietal arteryCentral (rolandic) sulcal artery Branch to angular gyrus Precentral (pre-rolandic) sulcal artery Terminal branches of posteriorPrefrontal sulcalcerebral arteryarteryTerminal branches ofanterior cerebralarteryLateral frontobasal(orbitofrontal) artery Left middle cerebral arteryLeft anteriorcerebral artery OccipitotemporalAnterior communicating arterybranchesRight anterior cerebral arteryPosterior temporal branchMiddle temporal branch Left internal carotid arterySuperior and inferior terminal branches (trunks)Polar temporal arteryAnterior temporal branchParacentral artery PosteriorPericallosal arteryMedialfrontalCingular branches IntermediatebranchesRight posterior cerebral artery Anterior Precuneal artery Callosomarginal Dorsal branch artery to corpus callosumParietooccipital branch Polar frontal arteryCalcarine branchRight anteriorcerebral arteryMedial fronto-basal (orbito-frontal) artery Anterior communicating artery (cut)Medial occipital arteryDistal medial striate arteryPosterior temporal branch(recurrent artery of Heubner)Anterior temporal branchRight internal carotid artery Posterior communicating arteryNote: Anterior parietal (postcentral sulcal) artery also occurs as separate anterior parietal and postcentral sulcal arteries15 20. NEUROANATOMY Arteries of Posterior Cranial Fossa Thalamogeniculate arteriesLateral and medial geniculate bodies of left thalamus Anterior choroidal artery Choroid plexuses of lateral ventriclesCrura of fornix Pulvinars of left and right thalami Splenium of corpus callosumAnterolateral central(lenticulostriate) arteriesOccipital (posterior) horn of right lateral ventricleHeads of caudate nucleiRight dorsal branch to corpus callosum (posterior pericallosal artery) Septum pellucidum Parietooccipital Branches ofCorpus callosum right posterior Calcarinecerebral arteryAnteriorcerebral arteriesLongitudinalcerebralfissure Superior colliculi Superior vermianOptic nerve (II) branchIVOphthalmic artery III Posterior medial Vchoroidal artery Anterior cerebral arteryto choroid plexusof 3rd ventricle MiddleVIII cerebral arteryPosterior lateralchoroidal arteryPosteriorVIIcommunicating arteryVI Lateral (marginal) branch IX Thalamoperforating arteriesX Inferior vermian artery Left internal carotid artery (phantom)XI Basilar arteryChoroidal branch to 4th ventricle (phantom) andPontine arteries Cerebellar tonsillar branch Labyrinthine (internal acoustic) artery of posterior inferior cerebellar artery Posterior cerebral arteryOutline of 4th ventricle (broken line) Superior cerebellar arteryPosterior meningeal branch of vertebral arteryAnterior inferior cerebellar artery Posterior inferior cerebellar artery (PICA) Anterior meningeal branch of vertebral artery Left posterior spinal artery Temporal branches of posterior cerebral artery Left vertebral arteryAnterior spinal artery16 21. Veins of Posterior Cranial FossaNEUROANATOMY Left superior and inferior colliculiLeft pulvinarBasal vein (Rosenthal)Right pulvinar Posterior mesencephalic veinInternal cerebral veinsMedial geniculate bodySplenium of corpus callosumLateralGreat cerebral vein (Galen)mesencephalic vein Dorsal vein of corpus callosumLateral geniculate body Inferior sagittal sinus Left thalamus Straight sinus (cut surface)Falx cerebri Optic tractConfluence of sinusesTentoriumInferior thalamo- cerebelli (cut) Left transversestriate veins sinus (cut)Deep middlecerebralSuperiorvein (cut)sagittalsinusAnteriorcerebralveinOpticnerve (II) C C CL D F LTUSuperiorvermian N PveinUInferior vermian veinAnterior ponto- Falx cerebelli (cut)mesencephalic vein Tand occipital sinusInferior cerebellarTrigeminal nerve (V)hemispheric veinsTransverse pontine vein Intraculminate veinPetrosal vein (drainingSuperior cerebellar vein (inconstant)to superior petrosal sinus) Preculminate vein Lateral pontine vein Precentral cerebellar vein Anteromedian medullary vein Superior retrotonsillar vein (Inferior retrotonsillar)Parts of cerebellum Vein of lateral recess of 4th ventricle vein of cerebellomedullaryL LingulaTU Tuber Superior, middle andcisternCLCentral lobule P Pyramid inferior cerebellar peduncles Posterior spinal veinC Culmen U UvulaD DecliveN Nodule Anterior spinal vein4th ventricleF Folium T Tonsil17 22. NEUROANATOMY Deep Veins of Brain Longitudinal cerebral fissureAnterior cerebral veins Rostrum of corpus callosumSeptum pellucidum Anterior vein of septum pellucidumHead of caudate nucleusAnterior vein of caudate nucleus Transverse veins of caudate nucleusInterventricular foramen (Monro) Columns of fornix Superior thalamostriate vein Superior choroid vein and choroid plexus of lateral ventricleThalamusTela choroidea of 3rd ventricleLateral direct veinPosterior vein of caudate nucleus Internal cerebral veinsBasal vein (Rosenthal) Great cerebral vein (Galen)Inferior sagittal sinus Straight sinusTentorium cerebelli Transverse sinusConfluence of sinuses Superior sagittal sinusDissection: superior view Uncal veinAnterior cerebral vein Superficial middle cerebral vein (draining to sphenoparietal sinus)Optic chiasmDeep middle cerebral veinCerebral crusBasal vein (Rosenthal)Lateral geniculate bodyInferior cerebral Medial geniculate bodyveins Pulvinar of thalamus Splenium of corpus callosum Great cerebral vein (Galen) Inferior anastomotic vein (Labb) Dissection: inferior view18 23. Subependymal Veins of Brain NEUROANATOMYPosterior veins of septum pellucidumLateral direct vein Superior thalamic veinsPosterior terminal vein of caudate nucleus(posterior part of thalamostriate vein)Superior choroid vein Internal cerebral veins (right and left) Transverse veins of caudate nucleusMedial (atrial) vein of lateral ventricleSuperior thalamostriate veinLateral (atrial) vein of lateral ventricleLateral ventricle Splenium of corpus callosum Anterior vein of caudate nucleus Great cerebral vein (Galen) Anterior vein of septum pellucidumDorsal vein of corpuscallosum Genu of corpusInferior sagittal callosumsinusInternaloccipital veinStraight sinusOccipital(posterior)horn oflateralventricleInterventricularforamen (Monro)Anterior commissureInterthalamic adhesionAnterior cerebral veinOptic chiasmCerebellum 3rd ventricle Deep middle cerebral vein Inferior thalamostriate veins Basal vein (Rosenthal)Temporal (inferior) horn of lateral ventriclePosterior mesencephalic veinSuperior vermian veinHippocampal and inferior ventricular veinsCerebral aqueduct Veins on lateral wall of ventricle4th ventricle Veins on medial wall and floor of ventricleLateral and median apertures of 4th ventricleAll other veins19 24. NEUROANATOMY Hypothalamus and Hypophysis Septum pellucidum Thalamus FornixHypothalamic sulcusAnterior commissure Paraventricular PosteriorPrincipalDorsomedialnuclei ofSupraoptichypothalamus Ventromedial Arcuate (infundibular) MammillaryMammillothalamic tractOptic chiasmDorsal longitudinal Infundibulum (pituitary stalk) fasciculus and otherdescending pathwaysHypophysis (pituitary gland)Lamina terminalis Hypothalamicsulcus Paraventricular hypothalamic nucleusSupraoptic hypothalamic nucleusSupraopticohypophyseal tract Tuberohypophyseal tractMammillary Hypothalamohypophyseal tract body Infundibulum (pituitary stalk)Arcuate (infundibular) nucleusPars tuberalisMedian eminenceof tuber cinereumAdenohypophysis Fibrous trabecula(anterior lobe ofNeurohypophysispituitary gland)Pars intermedia Infundibularstem (posterior lobe of pituitary gland)Pars distalisInfundibularprocessCleft20 25. Arteries and Veins of Hypothalamus and Hypophysis NEUROANATOMY Hypothalamic vessels Primary plexus of hypophyseal portal systemSuperiorhypophysealarteryLong hypophyseal portal veinsArtery of trabeculaShort hypophyseal portal veinsTrabecula (fibrous tissue)Efferent hypophyseal vein Efferent hypophyseal veinto cavernous sinusto cavernous sinusSecondary plexusNeurohypophysisof hypophyseal(posterior lobe ofportal system pituitary gland)Capillary plexus ofinfundibular processAdenohypophysis(anterior lobe ofpituitary gland) Efferent hypophyseal vein to cavernous sinus Inferior hypophyseal arteryEfferent hypophysealveins to cavernous sinus 21 26. NEUROANATOMYRelation of Spinal Nerve Roots to VertebraeL4C1C1 spinal nerve exitsBaseC1above C1 vertebraof skullC2 L4 C2C3Cervical C3C4enlargementC4 L5C5 C5 C6 C8 spinal nerveL5C6 C7 exits belowC7C7 vertebraC8(there are 8 cervical T1 nerves but only T1 7 cervical vertebrae)T2T2 S1 T3 T3T4T4 T5S2T5 T6 T6 T7 Lumbar disc protrusion does not usually affect T7 nerve exiting above disc. Lateral protrusion T8 at disc level L45 affects L5 spinal nerve, notT8 T9 L4 spinal nerve. Protrusion at disc level L5S1 T9 affects S1 spinal nerve, not L5 spinal nerveT10T10 T11 LumbarT11 enlargement T12L4 T12L1Conus medullaris(termination ofL1spinal cord) L4 L2 L2L5L3 L5 L3Cauda equinaInternal terminal L4filum (pial part)L4 L5 S1 L5 Sacrum S2 S1S3ExternalS2terminal filum(dural part)S3 Termination ofS4 S4dural sacS5S5Coccygeal nerveCoccyx Coccygeal nerve Cervical nerves Thoracic nerves Medial protrusion at disc level L45 rarely affects Lumbar nerves L4 spinal nerve but may affect L5 spinal nerve Sacral and coccygeal nerves and sometimes S14 spinal nerves22 27. Autonomic Nervous System: General TopographyNEUROANATOMYOculomotor nerve (III)Ciliary ganglionFacial nerve (VII) Pterygopalatine ganglion Glossopharyngeal nerve (IX) Otic ganglion Vagus nerve (X) Chorda tympani nerve Internal carotid nerve and plexus Lingual nerve Superior cervical sympathetic ganglion Submandibular ganglion C4 spinal nerve Pharyngeal and superior laryngeal branches of vagus nerveMiddle cervical sympathetic ganglionVertebral ganglion Recurrent laryngeal branch of vagus nerve Cervicothoracic (stellate) ganglion Superior cervicalCardiac branches Inferior cervicalof vagus nerve Sympathetic trunk Thoracic Superior Cardiac plexusCervical (sympathetic)cardiac nerves Middle Anterior InferiorPulmonary plexuses PosteriorThoracic (sympathetic) cardiac nervesEsophageal plexus 6th intercostal nerve Thoracic aortic plexus (ventral ramus of T6 spinal nerve)Anterior vagal trunk Sympathetic trunkPosterior vagal trunk6th thoracic sympathetic ganglionCeliac ganglionGray and white rami communicantesCeliac trunk and plexus Greater splanchnic nerve Superior mesenteric ganglionLesser splanchnic nerve Superior mesenteric artery Least splanchnic nerveand plexus Aorticorenal ganglionIntermesenteric(abdominal aortic) plexusLumbar splanchnic nerves (sympathetic) Inferior mesenteric ganglionGray rami communicantes Inferior mesenteric arterySacral splanchnic nerves (sympathetic) and plexusPelvic splanchnic nervesSuperior hypogastric plexus(sacral parasympatheticoutflow)Parasympathetic branch frominferior hypogastric plexus to Sciatic nervedescending colon Inferior hypogastric Hypogastric nerves (pelvic) plexusRectal plexus Vesical plexus Sympathetic fibers Parasympathetic fibersProstatic plexus23 28. NEUROANATOMYSpinal Nerve Origin: Cross Sections Section through thoracic vertebra Aorta Body of vertebraFat in epidural space Dura materSympathetic ganglion Arachnoid mater*Ventral rootSubarachnoid spaceWhite and gray ramicommunicantes Pia mater*RecurrentSpinal nervemeningeal Ventral ramusbranches of (intercostal nerve)spinal nerveDorsal ramusPleuraLung Spinal sensory (dorsal root) ganglionDorsal rootLateral horn ofgray matter of spinal cord Section through lumbar vertebraof dorsal Lateral branch ramusSympathetic of spinalganglionDura mater Medial branchnerve Gray ramusArachnoid mater Internal vertebral communicans (epidural) venous plexusVentral root Fat in epidural Spinal nerve space Ventral ramus (contributes to lumbar plexus)Dorsal ramusDorsal and ventral Spinal sensory (dorsal root) ganglionroots of lumbar and Dorsal rootsacral spinal nervesforming cauda equinaConus medullaris *Leptomeninges24 29. Olfactory Nerve (I): Schema NEUROANATOMY Subcallosal (parolfactory) areaSeptal area and nucleiOlfactory bulb cells: schema Fibers from ContralateralEfferent fibers toFibers toolfactory bulbolfactory bulbAfferent fibers from bulbAnterior commissureto central connectionsand contralateral bulbMedialolfactory striaGranule cell (excited byand inhibiting to mitraland tufted cells)Mitral cellRecurrent processTufted cellPeriglomerularcellGlomerulusOlfactorynerve fibersOlfactory cells Olfactory tract Olfactory mucosaOlfactory trigone and olfactory tubercle Olfactory nerves (I) Lateral olfactory stria UncusOlfactory bulb Lateral olfactory tract nucleusHippocampal Cribriform plate of ethmoid bone fimbria Anterior perforated substanceAnterior olfactory nucleusAmygdaloid body (phantom)Dentate gyrusPiriform lobeParahippocampal gyrus25 30. NEUROANATOMY Optic Nerve (II) (Visual Pathway): SchemaGCentral darkerGcircle represents macular zoneOverlappingLighter shadesA visual fieldsrepresentA monocular fields BB Each quadrant HHa different color Projection onR RCC Projection on right retinaleft retinaP P ChoroidChoroidOptic nerves (II)Optic chiasm PeripheryMacula Structure of retina: schemaProjection on rightProjection on left A Amacrine cells dorsal lateraldorsal lateral B Bipolar cellsgeniculate nucleusgeniculate nucleus C Cones Optic tracts G Ganglion cells H Horizontal cells P Pigment cellsLateral R Rods geniculatebodiesOptic radiation Optic radiation Calcarine sulcus Calcarine sulcus Projection on left Projection on right occipital lobe occipital lobe26 31. Oculomotor (III), Trochlear (IV) and Abducent (VI) Nerves: SchemaNEUROANATOMY Long ciliary nerve Ciliary ganglionShort ciliary nervesPosterior ethmoidal nerve Abducent nucleus Anterior ethmoidal nerveSensory root of ciliary ganglionTrochlear nucleus Superior oblique muscle Sympathetic root of ciliary ganglionLevator palpebrae Oculomotor nucleussuperioris muscleSuperior division of oculomotor nerveSuperiorAccessory oculomotorrectus muscleFrontal nerve (cut)(Edinger-Westphal)nucleus (parasympathetic)Lacrimal nerve (cut) Nasociliary nerve Trochlear nerve (IV) Oculomotor nerve (III)Ophthalmic nerve (V1) Infraorbital nerve Abducentnerve (VI)Zygomatic nerve (cut)Pterygopalatine ganglionMandibular nerve (V3) Inferior oblique muscleInternal carotid arteryCiliary muscleInferior division ofand nerve plexusoculomotor nerve Dilator muscle of pupil Maxillary nerve (V2) Medial rectus muscle Sphincter muscle of pupil Lateral rectus muscle andInferior rectus muscle abducent nerve (turned back) Efferent fibers Afferent fibersParasympathetic root Cavernous plexusof ciliary ganglion Sympathetic fibersCommon tendinous ring Parasympathetic fibers27 32. NEUROANATOMY Trigeminal Nerve (V): Schema Trigeminal nerve (V) ganglion and nucleiOphthalmic nerve (V1) Motor nucleus Efferent fibersMesencephalic nucleus Afferent fibers Tentorial (meningeal) branch Principal sensory nucleus Proprioceptive fibersNasociliary nerveSpinal tract and nucleus Parasympathetic fibersLacrimal nerve Sympathetic fibers Sensory root ofciliary ganglionFrontal nerveCiliary ganglionPosterior ethmoidal nerve Long ciliary nerveShort ciliary nerves Anterior ethmoidal nerveSupraorbital nerveSupratrochlear nerve Infratrochlear nerve Internal nasal branches and External nasal branches of anterior ethmoidal nerve Maxillary nerve (V2) Meningeal branch Zygomaticotemporal nerve Zygomaticofacial nerve Zygomatic nerve Infraorbital nerve Pterygopalatine ganglion Superior alveolar branches of infraorbital nerve Nasal branches (posterior superior lateral, nasopalatine Facial nerve (VII) and posterior superior medial)Chorda tympani nerve Nerve (vidian) of pterygoid canal (from facial nerve [VII] and carotid plexus) Pharyngeal branch Greater and lesser palatine nerves Deep temporal nerves Superficial (to temporalis muscle) temporal branchesLateral pterygoidArticular branchand masseteric nervesand anterior auricular nervesTensor veli palatini andmedial pterygoid nerves Auriculotemporal nerveBuccal nerveSubmandibular InferiorganglionParotid branchesalveolar nerveMental nerveMeningeal branch Inferior dental plexus Mylohyoid nerveOtic ganglionLesser petrosal nerve (from Lingual nerveMandibular nerve (V3) Tensor tympani nerveglossopharyngeal nerve [IX])28 33. Facial Nerve (VII): SchemaNEUROANATOMY Greater petrosal nerve Facial nerve (VII) Internal acoustic meatusDeep petrosal nerve (from internal carotid plexus) Geniculate ganglionIntermediate nerve Lesser petrosal nerveInternal carotid plexus Motor nucleus of facial nerve(on internal carotid artery)Nerve (vidian) of pterygoid canal Superior salivatory nucleus Otic ganglion Solitary tract nucleusPterygopalatine ganglion Facial muscles Frontal belly (frontalis) of occipitofrontalis Orbicularis oculi Corrugator supercilii Zygomaticus major Zygomaticus minor Temporal bran Procerus Levator labii superioris Levator labii superioris che alaeque nasi s Levator anguli oris NasalisZygomatic branches Depressor septi nasi anterior 23 Occipital Taste: tongue belly ofBuccal(occipitalis) of Orbicularis branches orisoccipitofrontalis muscle DepressorOccipitalh anc anguli orisbranch ofposterioral br Depressor labiiauricularCer vic inferioris nerve Mentalis Branches to auricular muscles (Risorius)Posterior auricular nerve al (not shown) Margin ular Nerve to stapedius muscle man dib BuccinatorbranchStylomastoid foramen Platysma Tympanic plexusTympanic nerve (Jacobson) Sublingual gland (from glossopharyngeal nerve)Submandibular gland Glossopharyngeal nerve (IX)Efferent fibers Submandibular ganglion Digastric muscle (posterior belly)Afferent fibersParasympathetic fibersLingual nerve (from trigeminal nerve)Stylohyoid muscleSympathetic fibersChorda tympani nerveCaroticotympanic nerve (from internal carotid plexus)29 34. NEUROANATOMY Vestibulocochlear Nerve (VIII): SchemaAfferent fibersFacial canalTympanic cavity Geniculum of facial nerve (site of geniculate ganglion)Chorda tympani nerveGreater petrosal nerveHead of malleusCochlear (spiral) ganglion IncusVestibular nerve Cochlear nerve Motor root of facial nerve and intermediate nerve Vestibulocochlear nerve (VIII) Medulla oblongata (cross section) Ampulla of lateral semicircular duct Internal Medialacoustic Ampulla of superior meatus semicircular duct VestibularSuperior nuclei Anterior Utricle Cochlear (diagrammatic)InferiornucleiPosterior Ampulla of posterior Lateral semicircular duct Inferior cerebellar peduncle (to cerebellum)Saccule Superior division Vestibular ganglion of vestibular nerve Inferior division30 35. Glossopharyngeal Nerve (IX): SchemaNEUROANATOMYEfferent fibers Spinal tract and spinal nucleus of trigeminal nerveAfferent fibersSolitary tract nucleusParasympathetic fibersTympanic nerve (Jacobson)Nucleus ambiguusTympanic cavity and plexusInferior salivatory nucleus Stylomastoid foramenGeniculate ganglion of facial nerve Caroticotympanic nerve (from internal carotid plexus) Greater petrosal nerveDeep petrosal nerveNerve (vidian) of pterygoid canal Lesser petrosal nervePterygopalatine ganglionMandibular nerve (V3) Otic ganglion Auriculotemporal nerve Parotid gland Tubal branch of tympanic plexus Pharyngotympanic (auditory) tube and pharyngeal openingStylopharyngeus muscle (and branchGlossopharyngealfrom glossopharyngeal nerve)nerve (IX) Jugular foramenCommunication to auricularbranch of vagus nerveSuperior andInferior ganglia ofGlossopharyngeal nerveCommunication to facial nerve (VII)Taste andsomatic Vagus nerve (X)sensation:posteriorSuperior cervical1 3 of tonguesympathetic ganglion Sympathetic trunk Carotid branch of glossopharyngeal nerveInternal carotid artery Pharyngeal plexus Carotid sinusPharyngeal, tonsillar and lingualbranches of glossopharyngeal nerveCarotid body Common carotid artery Pharyngeal branch of vagus nerve External carotid artery 31 36. NEUROANATOMYVagus Nerve (X): Schema Posterior nucleus of vagus nerve (parasympathetic SEE ALSO PLATE 160and visceral afferent)Glossopharyngeal nerve (IX) Meningeal branch of vagus nerveSolitary tract nucleus (visceralafferents including taste)Auricular branch of vagus nerve Spinal tract and spinalPharyngotympanic (auditory) tube nucleus of trigeminal nerve (somatic afferent)Levator velipalatini muscle Nucleus ambiguus(motor to pharyngealSalpingopharyngeusand laryngeal muscles)muscle Cranial root of accessory nerve* Palatoglossus muscle(see next plate) PalatopharyngeusVagus nerve (X) muscleJugular foramen Superior pharyngeal constrictor muscle Superior ganglion of vagus nerve Stylopharyngeus muscleInferior ganglion of vagus nerveMiddle pharyngeal constrictor muscle Pharyngeal branch of vagus nerve (motor to muscles of palate and lower pharynx; sensory to lower pharynx)Inferior pharyngeal constrictor muscleCommunicating branch of vagus nerve toCricothyroid muscle carotid branch of glossopharyngeal nerveTrachea Pharyngeal plexus Esophagus Superior laryngeal nerve: Internal branch (sensory and parasympathetic) Right subclavian artery External branch (motor to cricothyroid muscle) Right recurrent laryngeal nerveSuperior cervical cardiac branch of vagus nerve Heart Inferior cervical cardiac branch of vagus nerveHepatic branch of anteriorThoracic cardiac branch of vagus nervevagal trunk (in lesser omentum) Left recurrent laryngeal nerve (motor to muscles of larynx Celiac branches from anterior except cricothyroid; sensory and parasympathetic to and posterior vagal trunkslarynx below vocal folds; parasympathetic, efferent and to celiac plexusafferent to upper esophagus and trachea)Celiac and superior mesentericPulmonary plexusganglia and celiac plexusCardiac plexusHepatic plexus Esophageal plexusGallbladderand bile ducts Anterior vagal trunk LiverGastric branches of anterior vagal trunk(branches from posterior trunk behind stomach)Pyloric branchfrom hepatic plexusVagal branches (parasympathetic motor, secretomotor and afferent fibers) accompanyPancreas superior mesenteric artery and its branches usually as far as left colic (splenic) flexure Duodenum Small intestineAscending colonEfferent fibers CecumAfferent fibersAppendixParasympathetic fibers32 37. Accessory Nerve (XI): SchemaNEUROANATOMYSEE ALSO PLATE 28Nucleus ambiguusCranial root of accessory nerve (joins vagus nerveand via recurrent laryngeal nerve supplies muscles ofVagus nerve (X) larynx, except cricothyroid)*Spinal root ofaccessory nerve Jugular foramenForamenmagnumSuperior ganglionof vagus nerveAccessory nerve (XI)*Inferior ganglionof vagus nerveC1 spinal nerve C2 spinal nerveAccessory nerve(to sternocleidomastoidand trapezius muscles)Sternocleidomastoid muscle (cut)C3 spinal nerve C4 spinal nerveTrapezius muscle Efferent fibers Proprioceptive fibers*Recent evidence suggests that the accessory nerve lacks a cranial root and has no connection to the vagus nerve.Verification of this finding awaits further investigation.33 38. NEUROANATOMYHypoglossal Nerve (XII): SchemaHypoglossal nerve (XII) Meningeal branch(in hypoglossal canal) Hypoglossal nucleusSuperiorlongitudinal Intrinsic musclesTransverse of tongueand verticalStyloglossusInferiormusclelongitudinal Occipital condyle Inferior ganglion of vagus nerve Ventral rami of C1, 2, 3 form ansa cervicalis of cervical plexus Superior cervical sympathetic ganglion Superior root of Genioglossusansa cervicalis muscle Internal carotid artery Geniohyoid muscle Hyoglossus muscle Inferior root of ansa cervicalis Thyrohyoid muscle Ansa cervicalisOmohyoid muscleInternal jugular vein(superior belly)Sternohyoid muscle Common carotid artery Sternothyroid muscleOmohyoid muscle (inferior belly) Efferent fibers Afferent fibers34 39. Nerves of Heart NEUROANATOMY Superior cervicalSuperior cervical sympathetic ganglion sympathetic ganglionVagus nerve (X)Vagus nerve (X) (Conjoined sympathetic and Superior cervical vagal) superior cervical cardiac nerves(sympathetic) cardiac nerveMiddle cervical Superior cervicalsympathetic ganglion(vagal) cardiac nerveMiddle cervicalMiddle cervical(sympathetic) cardiac nervesympathetic ganglionPhrenic nervePhrenic nerveInferior cervical Middle cervical(vagal) cardiac nerve (sympathetic) cardiac nerveInferior cervical Vertebral ganglion (vagal) cardiac nerveInferior thyroid arteryVertebral ganglionVertebral arteryCervicothoracic(stellate) ganglionCervicothoracic(stellate) ganglionInferior cervical sympathetic Ansa subclaviacardiac nerves Recurrent laryngeal nerve Inferior cervical 3rd thoracic (sympathetic) cardiac nervessympathetic ganglion Thoracic cardiac branch Thoracic (sympathetic) of vagus nervecardiac branches 4th thoracicThoracic cardiac sympathetic ganglionbranch of vagus nerve Thoracic (sympathetic) cardiac branches Recurrent laryngealCardiac plexus nervePhrenic nerve (cut)35 40. NEUROANATOMYAutonomic Nerves and Ganglia of AbdomenRight sympathetic trunkAnterior, PosteriorThoracic ductvagal trunksRight greaterLeft gastric arteryand lesser and plexussplanchnicnerves Celiac gangliaRight phrenic nerveLeft greater splanchnic nerveInferior phrenic Left lesserarteries and plexusessplanchnic nerveRight greaterSplenic arteryand lesser and plexussplanchnicnerves Common hepatic artery and plexusRight suprarenalplexus Superior mesenteric ganglion and plexusRight aortico- Left aorticorenalrenal ganglion ganglionRight leastLeft sympatheticsplanchnic nerve trunkRight renalIntermesentericartery and plexus(aortic) plexusRightInferior mesentericsympathetic trunkganglionWhite and gray Left colic arteryrami communicantes and plexus Inferior mesentericCisterna chyli artery and plexusGray ramus communicans Left common iliac artery and plexus3rd lumbar ganglionof sympathetic trunk Superior rectal artery and plexus2nd and 3rd lumbarsplanchnic nervesSuperior hypogastric plexusRight ureter and plexus Internal and external iliac arteries andRight testicular (ovarian) plexusesartery and plexus Right and left4th lumbar splanchnic nervehypogastric nerves to inferior hypo-1st sacral gangliongastric (pelvic) plexusof sympathetic trunkGray rami communicantesLeft sacral plexus Pelvic splanchnic nerves36 41. Nerves of Stomach and Duodenum NEUROANATOMYRight and left inferior phrenic arteries and plexuses Hepatic branch of anterior vagal trunk Anterior and posterior layers of lesser omentum Anterior vagal trunk Branch from hepatic plexus to Celiac branch of posterior vagal trunk cardia via lesser omentumCeliac branch of anterior vagal trunk Right greater splanchnic nerveLeft gastric artery and plexus Vagal branch from hepatic plexus to pyloric part of stomach Hepatic plexus Right gastric artery and plexusAnterior gastricbranch of anteriorvagal trunk Left greater splanchnic nerveLeft lesser splanchnicnerveSplenic artery and plexus Celiac ganglia and plexusPlexus on gastro-omental(gastroepiploic) arteriesSuperior mesenteric artery and plexusPlexus on inferior pancreaticoduodenal arteryPlexus on first jejunal arteryPlexus on anterior superior and anteriorinferior pancreaticoduodenal arteries(posterior pancreaticoduodenal arteriesand plexuses not visible in this view)37 42. NEUROANATOMYNerves of Stomach and Duodenum (continued)Plexus on gastro-omentalPosterior gastric branch of posterior vagal trunk(gastroepiploic) arteriesHepatic branch of anterior vagal trunk via lesser omentumHepatic plexusBranch from hepatic plexus to cardia via lesser omentumRight gastricartery andRight inferior phrenic artery and plexusplexusPosterior vagal trunkCeliac branch of posterior vagal trunkCeliac branch of anterior vagal trunk Left gastric artery and plexus Left inferior phrenic artery and plexus Celiac ganglia and plexus Greater, lesser and least splanchnic nerves Aorticorenal ganglia Splenic artery and plexus Right phrenic nerve Greater,Phrenic ganglion Lesser,Branch from right inferior phrenic Leastplexus to cardia of stomach splanchnic nerves Right and left inferior phrenicarteries and plexusesAnterior vagal trunkPosterior vagal trunk View with stomach reflected cephaladPlexus onanterior superiorand anterior inferiorpancreatico- Celiac branchesduodenal arteriesof anteriorRight greater,lesser and posteriorPlexus on gastroduodenal arteryvagal trunksand leastPlexus on posterior superiorsplanchnic nervesand posterior inferior Left gastricpancreaticoduodenal arteries Celiac gangliaartery and plexusLeft greater,Superior mesenteric ganglion and plexus Right aortico-lesser and leastrenal ganglionsplanchnic nerves Superior mesenteric ganglion and plexusLeft aorticorenal ganglion38 43. Nerves of Small IntestineNEUROANATOMY Recurrent branch of left inferior phrenic artery and plexus to esophagus Anterior vagal trunk Posterior vagal trunk Hepatic branch of anterior vagal trunk (courses in lesser omentum, removed here) Celiac branches of anterior and posterior vagal trunks Inferior phrenic arteries and plexuses Left gastric artery and plexus Hepatic plexus Greater splanchnic nerves Right gastric artery and plexus (cut) Celiac ganglia and plexus Gastroduodenal artery and plexus Lesser splanchnic nerves Least splanchnic nerves Aorticorenal ganglia Superior mesenteric ganglion Intermesenteric (aortic) plexus Inferior pancreaticoduodenal arteries and plexuses Superior mesenteric artery and plexus Middle colic artery and plexus (cut) Right colic artery and plexus Ileocolic artery and plexus Superior mesenteric artery and plexus Peritoneum (cut edge) Mesenteric branches Mesoappendix (contains appendicular artery and nerve plexus) 39 44. NEUROANATOMY Nerves of Large IntestineAnterior vagal trunk and hepatic branchMarginal artery and plexusPosterior vagal trunkEsophagusCeliac branches of anteriorLeft inferior phrenicand posterior vagal trunks artery and plexusRight inferior phrenic artery and plexusLeft gastric arteryand plexusRight greatersplanchnic nerve Left greater splanchnicCeliac ganglia and plexusnerveRight lesser and Left suprarenalleast splanchnic plexusnerves Left lesser andRight aortico- least splanchnicrenal ganglion nervesSuperiorLeft aorticorenalmesentericganglionganglionLeft renal arteryand plexusMiddle colicartery1st left lumbarand plexussplanchnic nerveInferiorLeft lumbarpancreatico-sympathetic trunkduodenalarteriesIntermesentericand plexuses(aortic) plexusRight colic Left colic arteryarteryand plexusand plexus InferiorIleocolicmesentericartery ganglion, arteryand plexus and plexusCecal and Sigmoidappendiculararteriesarteriesand plexusesand plexuses SuperiorRight internal hypogastriciliac artery plexusand plexus (cut) SuperiorSacral sympathetic trunk rectal arteryRight sacral plexusand plexus Pelvic splanchnic nervesRight and left hypogastricMiddle rectal artery and plexusnerves Right inferior hypogastric Rectosigmoid (pelvic) plexusartery andplexus Vesical plexusNerves from inferior hypogastric (pelvic) Rectal plexusplexuses to sigmoid colon, descendingcolon and left colic (splenic) flexureUrinary bladder40 45. Nerves of Kidneys, Ureters and Urinary Bladder NEUROANATOMY Anterior vagal trunk Posterior vagal trunk Greater splanchnic nerve Celiac ganglia and plexus Lesser splanchnic nerve Superior mesenteric ganglion Least splanchnic nerve Aorticorenal ganglion Renal plexus and ganglion 2nd lumbar splanchnic nerve Renal and upper ureteric branches from intermesenteric plexus Intermesenteric (aortic) plexus Testicular (ovarian) artery and plexus Inferior mesenteric ganglion Sympathetic trunk and ganglion Middle ureteric branch Superior hypogastric plexus Sacral splanchnic nerves (branches from upper sacral sympathetic ganglia to hypogastric plexus) Gray ramus communicans Hypogastric nerves Sacral plexus Pudendal nerve Pelvic splanchnic nerves Inferior hypogastric (pelvic) plexus with periureteric loops and branches to lower ureter Rectal plexus Vesical plexus Prostatic plexus 41 46. NEUROANATOMYNerves of Pelvic Viscera: MaleAnterior vagal trunkT10 spinal nerve (anterior ramus) Posterior vagal trunkWhite and gray rami communicantes and Celiac branch Greater Lesser SplanchnicInferior phrenic arteries and plexusesnerves LeastLeft gastric artery and gastric plexusDiaphragmCeliac ganglia, plexus and trunk Left renal arteryLeft aorticorenal ganglion and plexusSuperior mesenteric ganglionL1 spinal nerve(anterior ramus)Superior mesenteric artery and plexusGray RamiIntermesenteric (aortic) plexus WhitecommunicantesInferior mesenteric ganglion,1st, 2nd, 3rd lumbar splanchnic nervesartery and plexus Gray rami communicantesUreter and ureteric plexus Sympathetic trunk and gangliaSuperior hypogastric plexus 5th lumbar splanchnic nerve Superior rectal artery and plexus L5 spinal nerve (anterior ramus)Hypogastric nerves Lumbosacral trunk Nerve from inferior hypogastric plexus Gray rami communicantes to sigmoid and descending colon (parasympathetic) S1 spinal nerve (anterior ramus)Sacral splanchnic nerves(sympathetic) Pelvic splanchnicnervesInferior hypogastric(parasympathetic)(pelvic) plexusObturator nerve Sacral plexusand arteryPiriformis muscleDuctus deferensand plexusGluteus maximusmuscle and sacro -Vesical plexustuberous ligament Rectal plexus(Ischio-)coccygeusmuscle andProstatic plexussacrospinous ligament Cavernous nerves Pudendal nerve of penis Levator ani muscleInferior anal (rectal) nervePerineal nerveDorsal nerve of penis Posterior scrotal nerves42 47. Nerves of Pelvic Viscera: FemaleNEUROANATOMYSympathetic trunk Abdominal aortaPeritoneumand L2 ganglionInferior vena cavaExtraperitonealWhite and (subserous)gray rami fasciacommunicantesCommoniliac vesselsand plexusLumbarsplanchnicUreternervesIntermesenteric(aortic) plexusOvarian arteryGray rami and plexuscommunicantes Superior hypogastric plexusL5 spinalnerve Sacralpromontory SuperiorRighthypogastrichypogastricplexusnerve (cut)Commoniliac arteryand plexusRight andleft sacral Uretersympathetictrunks andInternalganglia iliac arteryand plexus Sigmoid colonExternalPiriformis S1 iliac artery Right and leftmuscleand plexus hypogastric nervesS2UterusRight sympathetic trunkSacralS3splanchnicnerves S4Left hypogastric nerve(sympathetic)Inferior hypogastric (pelvic) plexusS5PudendalUterine (fallopian) tubenerveOvaryPelvicSymphyseal surface of pubissplanchnicnerves Urinary bladder(parasympathetic)Vesical plexus(Ischio-)coccygeus muscle Uterovaginal plexus Uterus (retracted)Rectal plexusRectum (retracted) 43 48. NEUROANATOMY Median NerveAnterior viewNote: Only muscles innervated by median nerve shown Musculocutaneous nerve Median nerve (C5, 6, 7, 8, T1) Medial Cords ofInconstant contribution PosteriorbrachialLateral plexusPronator teres muscle (humeral head) Medial cutaneous nerve of armArticular branch Medial cutaneous nerve of forearm Flexor carpi radialis muscleAxillary nervePalmaris longus muscle Radial nervePronator teres muscle (ulnar head)Ulnar nerveFlexor digitorum superficialis muscle(turned up) Flexor digitorum profundus muscle (lateral part supplied by median [anterior interosseous] nerve; medial part supplied by ulnar nerve) Anterior interosseous nerveFlexor pollicis longus musclePronator quadratus muscle Palmar branch of median nerve Cutaneous innervationAbductor pollicis brevisOpponens pollicisThenarSuperficial head ofmuscles flexor pollicis brevis(deep headsupplied byulnar nerve) Palmar viewCommunicating branchof median nerve with1st and 2nd ulnar nervelumbrical musclesCommon palmardigital nervesProper palmardigital nerves Dorsal branches to dorsum of middle and distal phalangesPosterior (dorsal) view44 49. Ulnar Nerve NEUROANATOMY Anterior view Note: Only muscles innervated by ulnar nerve shownUlnar nerve (C7, 8, T1)(no branches above elbow)Inconstant contributionMedial epicondyleArticular branch(behind condyle) Cutaneous innervationFlexor digitorum profundusmuscle (medial part only;lateral part supplied byanterior interosseousbranch of median nerve) Palmar viewFlexor carpi ulnaris muscle(drawn aside) Dorsal branch of ulnar nerve Posterior (dorsal) view Palmar branch Flexor pollicis brevis muscle (deep head only; superficialSuperficial branch head and other thenar muscles supplied by median nerve) Deep branchPalmaris brevis Adductor pollicis muscleAbductor digiti minimiFlexor digiti minimi brevis Hypothenar musclesOpponens digiti minimiCommon palmar digital nerveCommunicating branch of median nerve withulnar nerve Palmar and dorsal interosseous muscles 3rd and 4th lumbrical muscles (turned down)Proper palmar digital nerves(dorsal digital nerves are from dorsal branch)Dorsal branches to dorsum of middle and distal phalanges 45 50. NEUROANATOMYRadial Nerve in Arm and Nerves of Posterior ShoulderDorsal scapular nerve (C5) Posterior view Supraspinatus muscleSuprascapular nerve (C5, 6) Levator scapulae muscle (suppliedDeltoid muscle also by branches from C3 and C4)Teres minor muscleAxillary nerve (C5, 6) Rhomboid Superior lateral minor muscle cutaneous nerve of arm Radial nerve (C5, 6, 7, 8, T1) Inconstant contribution Rhomboid major muscleInferior lateralcutaneous nerve of armPosterior cutaneousnerve of forearm Infraspinatus muscleTeres major muscleLateral intermuscularseptumLower subscapular nerve (C5, 6)Posterior cutaneous nerve of arm(branch of radial nerve in axilla)Brachialis muscle (lateralpart; remainder of musclesupplied by musculo- Long headcutaneous nerve)Triceps brachii muscle Lateral head Medial head Brachioradialis muscle Triceps brachii tendon Medial epicondyle Extensor carpi radialis longus muscle Olecranon Extensor carpiAnconeus muscleradialis brevis muscle Extensor digitorum muscleExtensor carpi ulnaris muscle46 51. Radial Nerve in Forearm NEUROANATOMY Radial nerve (C5, 6, 7, 8, T1) Inconstant contributionSuperficial (terminal) branch Deep (terminal) branch Posterior viewLateral epicondyle Anconeus muscleBrachioradialis muscle Extensor carpi radialis longus muscle Supinator muscle Extensor carpi radialis brevis muscleExtensor carpi ulnaris muscleExtensor- supinator group of muscles Extensor digitorum muscle and extensor digiti minimi muscle Extensor indicis muscle Extensor pollicis longus muscleAbductor pollicis longus muscle Extensor pollicis brevis musclePosterior interosseous nerve(continuation of deep branch ofradial nerve distal to supinator muscle) Superficial branch of radial nerveSuperior lateral From axillary nervecutaneous nerveof armInferior lateralcutaneous nerveof armPosterior cutaneousnerve of armFrom radial nervePosterior cutaneousnerve of forearmSuperficial branch ofradial nerve and dorsaldigital branchesDorsal digital nervesCutaneous innervation fromradial and axillary nerves 47 52. NEUROANATOMYSciatic Nerve and Posterior Cutaneous Nerve of Thigh Posterior cutaneous nerve of thigh (S1, 2, 3) Greater sciatic foramen Inferior cluneal nerves Sciatic nerve (L4, 5, S1, 2, 3) Perineal branches Tibial division Common fibular (peroneal) of sciatic nervedivision of sciatic nerve Long head (cut) of Short head of biceps femoris muscle biceps femoris muscle Cutaneous innervation Adductor magnus muscle (also partially suppliedLong head (cut) by obturator nerve) of biceps femoris muscleSemitendinosus muscle Common fibular Semimembranosus muscle(peroneal) nerve Tibial nerve Articular branch Posteriorcutaneous nerve Articular branch of thighLateral sural Plantaris muscle cutaneous nerve Medial sural cutaneous nerve Sural communicating branchCommon fibularGastrocnemius muscle(peroneal) nervevia lateral suralcutaneous nerveSural nerveMedial suralcutaneous nerve Soleus muscle From sciatic nerveSuperficial fibular(peroneal) nerveTibial nerveSural nerve Lateral calcanealTibial nerveMedial branches via medialcalcaneal branchescalcanealbranchesLateral dorsal Medial and lateral cutaneous nerve plantar nerves48 53. Tibial Nerve NEUROANATOMYCommon fibular (peroneal) nerveTibial nerve(L4, 5, S1, 2, 3)Articular branch Lateral sural cutaneous nerve (cut)Medial suralcutaneous nerve (cut) Medial calcanealbranches(S1, 2)Articular branchesMedial From tibial nerve plantar nerve(L4, 5) Plantaris muscle Lateralplantar nerve(S1, 2)Gastrocnemiusmuscle (cut)Saphenous nerve(L3, 4)Sural nerveNerve to popliteus muscle (S1, 2) vialateral calcanealand lateral dorsal Popliteus muscle cutaneousbranches Interosseous nerve of legCutaneous innervation of sole Flexor Soleus muscle (cut andLateral calcaneal retinaculum partly retracted) branch of sural nerve (cut) Tibial Lateral plantar nervenerve Flexor digitorum Nerve to abductor longus muscle Medial calcanealdigiti minimi muscle branchQuadratus plantae Medial plantarmuscle and nerve Tibialis posterior muscle nerve Abductor digitiFlexor digitorum minimi musclebrevis muscle Deep branch toFlexor hallucis and nervelongus muscle interosseous Abductor hallucismuscles, muscle and nerve 2nd, 3rd and 4thFlexor hallucis lumbrical musclesSural nerve (cut) andbrevis muscleand nerve Adductor hallucismuscleLateral calcaneal branch 1st lumbrical muscle andSuperficial nerve branch to 4th interosseous MedialCommonmuscle calcaneal branchplantar and digital Flexor digiti minimi nervesbrevis muscle ProperCommon andFlexor retinaculum (cut) plantar Proper plantar digital digital nerves nerves Lateral dorsal cutaneous nerveNote: Articular branches not shown49 54. NEUROANATOMY Common Fibular (Peroneal) NerveLateral sural cutaneous nerve (phantom)Common fibular(peroneal) nerve(phantom)Articular branchesBiceps femoris tendonRecurrent articular nerve Common fibular (peroneal) nerve (L4, 5, S1, 2)Extensor digitorum longus muscle (cut)Head of fibulaDeep fibular (peroneal) nerve Fibularis (peroneus) longus muscle (cut)Tibialis anterior muscleSuperficial fibularCutaneous innervation(peroneal) nerveBranches of lateralExtensor digitorumsural cutaneous nervelongus muscleFibularis (peroneus)longus muscleExtensor hallucis longus muscle Fibularis (peroneus) brevis muscle Lateral sural cutaneous nerve Medial dorsal cutaneous nerve Superficial fibular (peroneal) nerveIntermediate dorsalLateral branch ofcutaneous nervedeep fibular (peroneal) nerve to Extensor hallucis brevis and Inferior extensor Extensor digitorum brevis musclesDeep retinaculum (partially cut)fibular(peroneal) Medial branch of nerve deep fibular Lateral dorsal cutaneous nerve(peroneal) nerve (branch of sural nerve) Sural nerve via lateral dorsal Dorsal digital nerves cutaneous branch50 55. Click any title below to link to that plate.Part 2 NeurophysiologyOrganization of the Brain: Cerebrum. . . . . . . 52The Cerebral Cortex . . . . . . . . . . . . . . . . . . . . 70Organization of the Brain: Cell Types. . . . . . . 53Descending Motor Pathways . . . . . . . . . . . . . 71Blood-Brain Barrier . . . . . . . . . . . . . . . . . . . . . 54 Cerebellum: Afferent Pathways. . . . . . . . . . . . 72Synaptic Transmission: Cerebellum: Efferent Pathways . . . . . . . . . . . . 73Morphology of Synapses . . . . . . . . . . . . . . . 55 Cutaneous Sensory Receptors . . . . . . . . . . . . . 74Synaptic Transmission:Neuromuscular Junction . . . . . . . . . . . . . . . 56Cutaneous Receptors:Pacinian Corpuscle. . . . . . . . . . . . . . . . . . . . 75Synaptic Transmission:Visceral Efferent Endings . . . . . . . . . . . . . . . 57 Proprioception and Reflex Pathways: I . . . . . . 76Synaptic Transmission: Proprioception and Reflex Pathways: II . . . . . 77Inhibitory Mechanisms . . . . . . . . . . . . . . . . 58 Proprioception and Reflex Pathways: III . . . . 78Synaptic Transmission: Proprioception and Reflex Pathways: IV. . . . . 79Chemical Synaptic Transmission . . . . . . . . . 59 Sensory Pathways: I . . . . . . . . . . . . . . . . . . . . . 80Synaptic Transmission:Temporal and Spatial Summation . . . . . . . . 60Sensory Pathways: II . . . . . . . . . . . . . . . . . . . . 81Cerebrospinal Fluid (CSF): Sensory Pathways: III. . . . . . . . . . . . . . . . . . . . 82 Brain Ventricles and CSF Composition . . . . 61 Visual System: Receptors. . . . . . . . . . . . . . . . . 83Cerebrospinal Fluid (CSF): Visual System: Visual Pathway . . . . . . . . . . . . 84 Circulation of CSF . . . . . . . . . . . . . . . . . . . . 62 Auditory System: Cochlea . . . . . . . . . . . . . . . . 85Spinal Cord: Ventral Rami. . . . . . . . . . . . . . . . 63 Auditory System: Pathways . . . . . . . . . . . . . . . 86Spinal Cord: Membranes and Nerve Roots . . 64 Vestibular System: Receptors . . . . . . . . . . . . . 87Peripheral Nervous System . . . . . . . . . . . . . . . 65 Vestibular System: Vestibulospinal Tracts. . . . 88Autonomic Nervous System: Schema . . . . . . . 66 Gustatory (Taste) System: Receptors . . . . . . . 89Autonomic Nervous System: Cholinergic and Adrenergic Synapses . . . . . 67Gustatory (Taste) System: Pathways . . . . . . . . 90Hypothalamus . . . . . . . . . . . . . . . . . . . . . . . . . 68Olfactory System: Receptors . . . . . . . . . . . . . . 91Limbic System . . . . . . . . . . . . . . . . . . . . . . . . . 69 Olfactory System: Pathway . . . . . . . . . . . . . . . 92 56. NEUROPHYSIOLOGY Organization of the Brain: Cerebrum Central sulcus (Rolando)Postcentral gyrusPrecentral gyrus Postcentral sulcusPrecentral sulcus Superior parietal lobuleInferior parietal lobuleSupramarginal gyrusAngular gyrusParietooccipitalsulcus Occipital pole Frontal poleCalcarine sulcus Lateral sulcus (Sylvius)Temporal pole Superior temporal gyrusInferior temporal gyrusMiddle temporal gyrusFrontal lobeParietal lobeTemporal lobeOccipital lobe Insula (island of Reil)FIGURE 2.1 ORGANIZATIONOF THEBRAIN: CEREBRUMThe cerebral cortex represents the highest center for sensory and coordinates smooth motor activities and processes muscle position.motor processing. In general, the frontal lobe processes motor, The brainstem (medulla, pons, midbrain) conveys motor and sensoryvisual, speech, and personality modalities. The parietal lobe information and mediates important autonomic functions. The spinalprocesses sensory information; the temporal lobe, auditory andcord receives sensory input from the body and conveys somatic andmemory modalities; and the occipital lobe, vision. The cerebellum autonomic motor information to peripheral targets (muscles, viscera).52 57. Organization of the Brain: Cell Types NEUROPHYSIOLOGYMultipolar (pyramidal)Bipolar cell of cranial n.cell of cerebral Unipolar cell ofmotor cortex sensory ganglia of cranial nn. Satellite cellsAstrocyteSchwann cell StriatedInterneurons (somatic) Blood vessel Free nerve endings muscle (unmyelinated fibers)Encapsulated endingMotorendplateSpecialized endingMultipolar somaticMuscle spindlemotor cell of nucleiUnipolar sensory cellof cranial nn.of dorsal spinalMultipolar cell root ganglionof lower brainInterneuronSatellite cellsmotor centersOligodendrocyte AstrocyteMyelinated afferentCorticospinalfiber of spinal nerve(pyramidal) fiber Multipolar visceralAxodendritic ending motor (autonomic)cell of spinal cordAxosomatic endingMyelin sheathAxoaxonic ending Autonomic preganglionicMultipolar somatic (sympathetic or para-Red:Motor neuronmotor cell ofsympathetic) nerve fiber Blue: Sensory neuronanterior hornMyelin sheathPurple: Interneuronof spinal cord Gray:Glial and Autonomic postganglionic neurilemmal cellsCollateral neuron of sympathetic or and myelin parasympathetic ganglionRenshaw interneuronNote: Cerebellar cells Satellite cells not shown here(feedback) Unmyelinated nerve fiberMyelinated somatic motor Schwann cellsfiber of spinal nerveMyelin sheathSchwann cellsMotor endplate with Endings on Unmyelinated fibersSchwann cell capcardiac muscleor nodal cellsStriated Free nerve endings(voluntary)Beadedmuscle varicosities and endings on Encapsulated ending smooth muscle and gland cellsMuscle spindle FIGURE 2.2 ORGANIZATION OF THEBRAIN: CELL TYPESNeurons form the functional cellular units responsible for (e.g., astrocytes, oligodendrocytes), satellite cells, and other spe-communication, and throughout the nervous system, they are cialized cells that optimize neuronal function, provide mainte-characterized by their distinctive size and shapes (e.g., bipolar, nance functions, or protect the nervous system.unipolar, multipolar). Supporting cells include the neuroglia 53 58. NEUROPHYSIOLOGY Blood-Brain Barrier Cell membraneBasementTight membranejunctionproteins CytoplasmRed bloodcellAstrocyte Capillaryfoot processeslumen Tight Capillary junction endothelial cell Astrocyte FIGURE 2.3 BLOOD-BRAIN BARRIERThe blood-brain barrier (BBB) is the cellular interface between theother substances (including many drugs) from the blood to theblood and the central nervous system (CNS; brain and spinal cord). interstitial space of the CNS is restricted by the BBB. CNS endothe-It serves to maintain the interstitial uid environment to ensurelial cells also exhibit a low level of pinocytotic activity across theoptimal functionality of the neurons. This barrier consists of the cell, so specic carrier systems for the transport of essential sub-capillary endothelial cells with an elaborate network of tight junc- strates of energy and amino acid metabolism are characteristic oftions and astrocytic foot processes that abut the endothelium andthese cells. The astrocytes help transfer important metabolites fromits basement membrane. The movement of large molecules and the blood to the neurons and also remove excess K and neuro- transmitters from the interstitial uid.54 59. Synaptic Transmission: Morphology of Synapses NEUROPHYSIOLOGYDendriteNode AxonDendritesMyelin sheath Numerous boutons (synaptic knobs) of presynaptic neurons terminating on a motor neuron and its dendritesEnlarged sectionof boutonAxon (axoplasm)Axolemma MitochondriaGlial processSynaptic vesiclesSynaptic cleftPresynaptic membrane(densely staining)Postsynaptic membrane(densely staining)Postsynaptic cellFIGURE 2.4 MORPHOLOGY OF SYNAPSESNeurons communicate with each other and with effector targets at lower gure shows an enlargement of one such synaptic bouton.specialized regions called synapses. The top gure shows a typical Chemical neurotransmitters are contained in synaptic vesicles,motor neuron that receives numerous synaptic contacts on its cellwhich can fuse with the presynaptic membrane, release the trans-body and associated dendrites. Incoming axons lose their myelinmitters into the synaptic cleft, and then bind to receptors situatedsheaths, exhibit extensive branching, and terminate as synapticin the postsynaptic membrane. This synaptic transmission results inboutons (synaptic terminals or knobs) on the motor neuron. The excitatory, inhibitory, or modulatory effects on the target cell. 55 60. NEUROPHYSIOLOGY Synaptic Transmission: Neuromuscular JunctionStructure of Neuromuscular JunctionActive zone Myelin sheathSchwann cell processNeurilemma Axoplasm AcetylcholineSchwann cell receptor sitesMitochondria Basement membrane Nucleus of Schwann cellPresynaptic membraneActive zoneSynaptic vesicles Synaptic troughBasement membrane Sarcolemma Nucleus of muscle cellMyofibrils Synaptic cleft Postsynaptic membraneJunctional fold SarcoplasmAcetylcholine receptor sitesFIGURE 2.5 STRUCTURE OF THE NEUROMUSCULAR JUNCTIONMotor axons that synapse on skeletal muscle form expanded termi-ately stimulated, release their neurotransmitter into the synapticnals called neuromuscular junctions (motor endplates). The motorcleft. The transmitter then binds to receptors that mediate depolar-axon loses its myelin sheath and expands into a Schwann ization of the muscle sarcolemma and initiate a muscle actioncellinvested synaptic terminal that resides within a trough in the potential. A single muscle ber has only one neuromuscular junc-muscle ber. Acetylcholine-containing synaptic vesicles accumu- tion, but a motor axon can innervate multiple muscle bers.late adjacent to the presynaptic membrane and, when appropri-56 61. Synaptic Transmission: Visceral Efferent EndingsNEUROPHYSIOLOGY Visceral Efferent Endings A. Smooth muscle B. Gland (submandibular)C. Neurosecretory (posterior pituitary)Sympathetic terminalendingPituicyte processesMucous cellsSmooth muscle cells (cut) Varicosity AxonAxon Schwann cell cap enclosing Schwann Schwann cell cap enclosing nerve axons cell cap nerve axons Fibroblast Schwann cell cap Capillary Schwann cellNeurosecretory Smooth muscle cellsSerous cells cap enclosing vesicles EndotheliumVaricosities Parasympathetic nerve axons terminal ending Collagen space Terminal endings Mast cellVaricosityBasement membrane FIGURE 2.6 VISCERAL EFFERENT ENDINGSNeuronal efferent endings on smooth muscle (A) and glands (Brosecretion) from expanded nerve terminal endings. This arrange-and C) exhibit unique endings unlike the presynaptic and postsy-ment allows for the stimulation of numerous target cells over anaptic terminals observed in neuronal and neuromuscular junc- wide area. Not all smooth muscle cells are innervated. They aretion synapses. Rather, neurotransmitter substances are released connected to adjacent cells by gap junctions and can thereforeinto interstitial spaces (A and B) or into the bloodstream (C, neu- contract together with the innervated cells.57 62. NEUROPHYSIOLOGYSynaptic Transmission: Inhibitory MechanismsIEE(Inhibitory(Excitatory (Excitatory fiber) fiber) fiber) Motor neuron Motorneuron I Axon (InhibitoryAxonfiber) mV20 mVA. Only E fires 90-mV spike 90 mV A. Only E fires in E terminal70EPSP in60motor 60EPSP in neuronmotor neuron7070B. Only I firesB. Only I fires Long-lasting partialMotor60 depolarization 70neuron in E terminalhyper-70 No response in polarized motor neuron 8070C. I fires before EC. I fires before E Partial60 depolarization Depolariza-20 of E terminaltion of motor 70 reduces spikeneuron less to 80 mV, thus80 mVthan if only80 releasing less E fires transmitter70 substance60Smaller EPSP inmotor neuron70 FIGURE 2.7 SYNAPTIC INHIBITORY MECHANISMSInhibitory synapses modulate neuronal activity. Illustrated here is presynaptic inhibition (left panel) and postsynaptic inhibition (rightpanel) at a motor neuron.58 63. Synaptic Transmission: Chemical Synaptic TransmissionNEUROPHYSIOLOGYExcitatory Inhibitory Synapticvesiclesin synapticbouton Presynaptic membrane Transmitter NasubstancesSynaptic cleft ClKPostsynapticmembraneWhen impulse reaches excitatory synapticAt inhibitory synapse, transmitter substance re-bouton, it causes release of a transmitterleased by an impulse increases permeability ofsubstance into synaptic cleft. This increases the postsynaptic membrane to Cl . K movespermeability of postsynaptic membrane toout of post-synaptic cell but no net flow of ClNa and K . More Na moves into postsy- occurs at resting membrane potentialnaptic cell than K moves out, due to great-er electrochemical gradient Synaptic boutonResultant net ionic current flow is in a direc- Resultant ionic current flow is in direction that tends totion that tends to depolarize postsynaptic cell.hyperpolarize postsynaptic cell. This makes depolariza-If depolarization reaches firing threshold, antion by excitatory synapses more difficultmore depolari-impulse is generated in postsynaptic cell zation is required to reach thresholdmsecCurrent 0 4 8 12 16 70 Potential (mV) Potential (mV)65 PotentialPotential75Current70 048 12 16 msec Current flow and potential change Current flow and potential changeFIGURE 2.8 CHEMICAL SYNAPTIC TRANSMISSIONChemical synaptic transmission between neurons may be excita- threshold for an action potential. During inhibition (right column),tory or inhibitory. During excitation (left column), a net increase inthe opening of K and Cl channels drives the membrane potentialthe inward ow of Na compared with the outward ow of K away from threshold (hyperpolarization) and decreases the proba-results in a depolarizing potential change (excitatory postsynaptic bility that the neuron will reach threshold (inhibitory postsynapticpotential [EPSP]) that drives the postsynaptic cell closer to its potential [IPSP]) for an action potential.59 64. NEUROPHYSIOLOGYSynaptic Transmission: Temporal and Spatial Summation Temporal and Spatial Summation of Excitation and Inhibition Excitatory fibersmV Excitatory fibers mV7070 AxonAxon Inhibitory fibers Inhibitory fibers A. Resting state: motor nerve cell shown with synaptic boutons of B. Partial depolarization: impulse from one excitatory fiber has excitatory and inhibitory nerve fibers ending close to it caused partial (below firing threshold) depolarization of motor neuron Excitatory fibers mV Excitatory fibersmV 7070 Axon Axon Inhibitory fibers Inhibitory fibers C. Temporal excitatory summation: a series of impulses in one D. Spatial excitatory summation: impulses in two excitatory fibers excitatory fiber together produce a suprathreshold depolarization cause two synaptic depolarizations that together reach firing that triggers an action potential threshold triggering an action potential Excitatory fibersmV Excitatory fibers mV7070 AxonAxon Inhibitory fibers Inhibitory fibers E. Spatial excitatory summation with inhibition: impulses fromE. (continued): motor neuron now receives additional excitatory two excitatory fibers reach motor neuron but impulses fromimpulses and reaches firing threshold despite a simultaneous inhibitory fiber prevent depolarization from reaching threshold inhibitory impulse; additional inhibitory impulses might still prevent firing CHART 2.1 SUMMARY OF SOME NEUROTRANSMITTERS AND WHERE WITHIN THE CENTRAL AND PERIPHERAL NERVOUSSYSTEM THEY ARE FOUND Transmitter Location Transmitter Location Acetylcholine Neuromuscular junction, autonomic end- Gas ings and ganglia, CNS Nitric oxide CNS, GI tract Biogenic aminesPeptides NorepinephrineSympathetic endings, CNS-EndorphinsCNS, GI tract DopamineCNS EnkephalinsCNS Serotonin CNS, GI tract Antidiuretic CNS (hypothalamus/posterior Amino acids hormonepituitary) -Aminobutyric CNS Pituitary-releasingCNS (hypothalamus/anterior acid (GABA) hormones pituitary) Glutamate CNS Somatostatin CNS, GI tract Purines Neuropeptide Y CNS Adenosine CNS Vasoactive Adenosine CNS intestinal peptide CNS, GI tract triphosphate (ATP)CNS, Central nervous system; GI, gastrointestinal.FIGURE 2.9 TEMPORAL AND SPATIAL SUMMATION Neurons receive multiple excitatory and inhibitory inputs. Tempo-tial (panel D). Both temporal and spatial summation can be modu-ral summation occurs when a series of subthreshold impulses in lated by simultaneous inhibitory input (panel E). Inhibitory andone excitatory ber produces an action potential in the postsynap- excitatory neurons use a wide variety of neurotransmitters, some oftic cell (panel C). Spatial summation occurs when subthreshold which are summarized here.impulses from two or more different bers trigger an action poten-60 65. Cerebrospinal Fluid (CSF): Brain Ventricles and CSF Composition NEUROPHYSIOLOGYLeft lateral phantom viewRight lateral ventricleFrontal (anterior) horn Central partLeft lateral Temporal (inferior) hornventricle Occipital (posterior) horn Cerebral aqueduct (Sylvius) 4th ventricle Left lateral aperture (foramen of Luschka) Left lateral recessLeft interventricularforamen (Monro)Median aperture (foramen of Magendie)3rd ventricle Central canal of spinal cord CHART 2.2 CSF COMPOSITION CSFBlood PlasmaNa (mEq/L) 140145135147K (mEq/L) 33.55.0Cl (mEq/L)11512095105HCO3 (mEq/L)20 2228Glucose (mg/dL) 5075 70110Protein (g/dL)0.050.076.07.8pH 7.37.357.45FIGURE 2.10 BRAIN VENTRICLES AND CSF COMPOSITIONCSF circulates through the four brain ventricles (two lateral ventri- secretes the CSF. Importantly, the CSF has a lower [HCO3 ] thancles and a third and fourth ventricle) and in the subarachnoidplasma and therefore a lower pH. This allows small changes inspace surrounding the brain and spinal cord. The electrolyte com- blood PCO2 to cause changes in CSF pH, which in turn regulatesposition of the CSF is regulated by the choroid plexus, which the rate of respiration (see Chapter 5). 61 66. NEUROPHYSIOLOGYCerebrospinal Fluid (CSF): Circulation of CSFChoroid plexus of lateralventricle (phantom) Superior sagittal sinus Cistern of corpus callosum Subarachnoid space Arachnoid granulations Dura mater ArachnoidInterventricularforamen (Monro)Choroid plexus of 3rd ventricle Cerebral aqueduct (Sylvius)Lateral aperture (foramen of Luschka)Choroid plexus of 4th ventricleMedian aperture(foramen of Magendie) Dura materArachnoidSubarachnoid space Central canal of spinal cord FIGURE 2.11 CIRCULATIONOF CEREBROSPINAL FLUIDCSF circulates through the four brain ventricles (two lateral ventri- reabsorbed into the venous system through the arachnoid granula-cles and a third and fourth ventricle) and in the subarachnoidtions and through the walls of the capillaries of the central nervousspace surrounding the brain and spinal cord. Most of the CSF is system and pia mater.62 67. Spinal Cord: Ventral Rami NEUROPHYSIOLOGYBase of skull C1 vertebra (atlas) C1 spinal nerve Cervical plexus C8 spinal nerve Brachial plexus T1 spinal nerveSpinal dura mater1st rib Filaments of spinal nerve roots Intercostal (T7 and T8) nerves T12 spinal nerve L1 12th ribvertebraConus medullaris Lumbar plexus L1 spinal nerve L5 vertebra Cauda equina S1 spinal nerve Sacral plexusSacrum (cut away)Termination of dural sac Sciatic nerve Coccygeal nerve Coccyx FIGURE 2.12 SPINAL CORDAND VENTRAL RAMI IN SITUThe spinal cord gives rise to 31 pairs of spinal nerves that distribute bers of these spinal nerves innervate skeletal muscle, and sensorysegmentally to the body. These nerves are organized into plexuses bers convey information back to the central nervous system fromthat distribute to the neck (cervical plexus), upper limb (brachial the skin, skeletal muscles, and joints.plexus), and pelvis and lower limb (lumbosacral plexus). Motor63 68. NEUROPHYSIOLOGY Spinal Cord: Membranes and Nerve RootsPosterior view Ventral root of spinal nerveDorsal root of spinal nerveSpinal sensory (dorsal root) ganglion Ventral ramus of spinal nerve Dorsal ramus of spinal nerveDura mater Arachnoid mater Subarachnoid spacePia mater overlying spinal cordFilaments of dorsal rootMembranes removed: anterior view(greatly magnified)Gray matter White matter Filaments of dorsal rootDorsal root of spinal nerve Filaments of ventral root Spinal sensory (dorsal root) ganglion Dorsal ramus of spinal nerve Ventral ramus of spinal nerve Ventral root of spinal nerveSpinal nerveGray and white ramicommunicantesFIGURE 2.13 SPINAL MEMBRANES AND NERVE ROOTSThe spinal cord gives rise to 31 pairs of spinal nerves that distribute The spinal cord is ensheathed in three meningeal coverings: thesegmentally to the body. Motor bers of these spinal nerves inner-outer, tough dura mater; the arachnoid mater; and the pia mater,vate skeletal muscle, and sensory bers convey information back which intimately ensheaths the cord itself. CSF bathes the cord andto the central nervous system from the skin, skeletal muscles, andis found in the subarachnoid space.joints.64 69. Peripheral Nervous System NEUROPHYSIOLOGY Posterior horn Dorsal root ganglion Sensory neuron cell body Dorsal root Anterior horn Motor neuron cell body Ventral root Peripheral nerveAxonMyelin sheath Motor neuron Sensory neuron Neuromuscular junctionSkin Muscle with FIGURE 2.14 PERIPHERAL NERVOUS SYSTEMThe peripheral nervous system (PNS) consists of all of the neural shown here (see Figure 2.15 for the autonomic nervous system).elements outside of the CNS (brain and spinal cord) and providesThe somatic component of the peripheral nerves contains boththe connections between the CNS and all other body organ sys- motor and sensory axons. Cell bodies of the motor neurons aretems. The PNS consists of somatic and autonomic components. The found in the anterior horn gray matter, whereas the cell bodies ofsomatic component innervates skeletal muscle and skin and issensory neurons are located in the dorsal root ganglia. 65 70. NEUROPHYSIOLOGY Autonomic Nervous System: SchemaOculomotor nerve (III)Intracranial vessels Facial nerve (VII)Ciliary ganglionGlossopharyngeal nerve (IX)Eye Pterygopalatine ganglion Medulla oblongata Lacrimal glandsVagus nerve (X)Otic ganglionParotid glandsC1 Gray ra ntes Submandibular ganglion Sublingual andmi C2 ica submandibular glandsommun C3 C4 Peripheral cranialand facial vessels C5 cC6 LarynxC7 TracheaC8 Bronchi LungsSweatT1gland T2 Pulmonary plexusT3 tesHeart Cardiac plexus Gray and white rami communicanT4 Greater SplanchnicPeripheral T5 Lesser nervesblood vessel Celiac ganglion T6Least StomachT7 Aorticorenal ganglionLiverT8GallbladderBile ductsT9Lumbar Pancreas T10 splanchnicSuperior mesenteric nervesganglion Suprarenal glands T11 Arrector (smooth) Kidneys T12 Inferior mesenteric muscle of hair follicle ganglion Note: Above threeL1 structures are shown at L2Intestines only one level butSuperior hypogastric occur at all levels L3plexus cantes L4 Descending colon L5 Sigmoid colonm uni Note: Blue-shadedS1 Rectum Inferior co m areas indicate zones of hypogastric parasympatheticS2 Urinary bl