An Illustrated Terminologia NeuroanatomicaA Concise Encyclopedia of Human Neuroanatomy

Hans J. ten Donkelaar David Kachlik R. Shane Tubbs

An Illustrated Terminologia Neuroanatomica

Hans J. ten Donkelaar • David Kachlík R. Shane Tubbs

An Illustrated Terminologia NeuroanatomicaA Concise Encyclopedia of Human Neuroanatomy

Hans J. ten Donkelaar935 Department of Neurology and Donders Center for Medical NeuroscienceRadboud University Medical CenterNijmegenThe Netherlands

R. Shane TubbsSeattle Science FoundationSeattle, WAUSA

David KachlíkDepartment of Anatomy, 2nd Faculty of MedicineCharles UniversityPragueCzech Republic

ISBN 978-3-319-64788-3 ISBN 978-3-319-64789-0 (eBook)https://doi.org/10.1007/978-3-319-64789-0

Library of Congress Control Number: 2018940431

© Springer International Publishing AG, part of Springer Nature 2018This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed.The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use.The publisher, the authors and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publisher nor the authors or the editors give a warranty, express or implied, with respect to the material contained herein or for any errors or omissions that may have been made. The publisher remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

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Recently, the terminology on the central nervous system (CNS), peripheral nervous system (PNS), and sensory organs (Organa sensuum) of the Terminologia Anatomica (1998) and the Terminologia Histologica (2008) has been merged and extensively updated by the FIPAT Working Group on Neuroanatomy. After discussion by FIPAT (Federative International Programme for Anatomical Terminology) in Istanbul, Turkey (August 31–September 1, 2015), and after consultation of the IFAA (International Federation of Associations of Anatomists) Member Societies and validation by the IFAA Executive (September 22, 2016, Göttingen, Germany), the Terminologia Neuroanatomica (TNA) was accepted by FIPAT (September 24, 2016, Göttingen, Germany) as its official terminology. It has become available online as TNA February 2017 (TNA; FIPAT 2017b; http://FIPAT.library.dal.ca). Because of its clinical and functional relevance, the TNA includes the blood supply to the CNS (Vasa sanguinea enceph-ali and Vasa sanguinea medullae spinalis) to ensure it has a more or less complete list of terms pertaining to the human nervous system. Chair (John Fraher, Cork, Ireland) and Secretary (Pierre Sprumont, Fribourg, Switzerland) of FIPAT gave permission to use the TNA terminol-ogy in this book.

The TNA uses a more natural hierarchical, embryologically based, classification of brain structures for the prosencephalon (forebrain; see Puelles 2013; Puelles et al. 2013) as imple-mented in the revised version of the Terminologia Embryologica (TE2; FIPAT 2017a), which also has come online in February 2017. These major changes in the hierarchy of terms on the CNS prompted the publication of an introductory paper on the TNA in Clinical Anatomy (ten Donkelaar et al. 2017). To make the TNA more useful to a wider audience, the idea of An Illustrated TNA arose with an alphabetical list of neuroanatomical terms in standardized English with American English spelling, the TNA nomenclature in Latin, and illustrations, so A Concise Encyclopedia of Human Neuroanatomy following the excellent example of Radivoj Krstić’s Illustrated Encyclopedia of Human Histology (Krstić 1984). The concise encyclope-dia also includes the sensory organs; those of the skin, muscles, and tendons are presented in the PNS section; and the retina, the internal ear (vestibular and auditory receptors), and the olfactory and gustatory organs are presented in the Organa sensuum section of the TNA, as well as the enteric nervous system.

Contents

The Illustrated TNA includes an alphabetical list of English official terms and synonyms with the official Latin terms and synonyms from the TNA. With regard to the entries, the name of the item in standardized English is given, followed by synonyms and the official TNA Latin term, Latin synonyms and eponyms, a short description, and in many cases one or more illus-trations. For the brief discussions, Lockard’s (1977) Desk Reference of Neuroanatomy (Springer, New  York-Heidelberg-Berlin) and Hirsch’s (2000) Dictionary of Human Neuroanatomy (Springer, Berlin-Heidelberg) served as examples. To facilitate the use of illus-trations, certain entries such as the gyri or sulci of the cerebral cortex are presented together with extensive cross-references. Terms that form part of a certain structure (such as the

Preface

vi

amygdaloid body, the thalamus, and the hypothalamus) are listed under that structure. Similarly, the subarachnoid cisterns are discussed under the heading Cisterns. Segments and branches of arteries are discussed under the main artery, for example, the A1–A5 segments under the ante-rior cerebral artery. Most nerves can be found following their origin from the brachial, cervi-cal, and lumbosacral plexuses. However, the major nerves of the limbs are discussed separately as are the cranial nerves. Nuclei can be found by their English name or under Nuclei by their eponym.

Illustrations form an important part of this book. They were taken from ten Donkelaar (2011), ten Donkelaar and Oostra (2014), and ten Donkelaar et al. (2006, 2014), and from the collection of Shane Tubbs, many of them were prepared by Mr. Ad Gruter (Nieuwegein) and Mr. David Fisher (Birmingham, Alabama), respectively. Several pictures were contributed by the late Chris van Huijzen (Nijmegen) and Bob Morreale (Mayo Clinic, Rochester) or other-wise taken from the literature. For the forebrain the superb Weigert-stained sections from Jelgersma’s Atlas (Atlas Anatomicum Cerebri Humani, Scheltema & Holkema, Amsterdam, 1931) were used, as published in ten Donkelaar (2011) with permission from the Board of the Anatomical Museum, Leiden University Medical Center. Several plates from the third edition of Olszewski and Baxter’s Cytoarchitecture of the Human Brain Stem, edited by Jean Büttner- Ennever and Anja Horn, were kindly provided by Karger, Basel. Dr. Thomas Karger is thanked for his kind permission to use these excellent plates. Several histological photomicrographs were taken from Finn Geneser’s Textbook of Histology (Munksgaard, Copenhagen, 1986) and histological drawings from Radivoj Krstić’s Die Gewebe des Menschen und der Säugetiere (2nd ed., Springer, Berlin-Heidelberg-New York, 1988). Both authors kindly granted their per-mission for the use of their excellent figures. Mrs. Britta Østergaard, publishing editor at Munksgaard, was of great help in providing many digital figures from Genesers histologi (Munksgaard, Copenhagen, 2012). Additional histological pictures were kindly provided by Geoffrey Meyer (Meyer 2016). For the thalamus, Anne Morel kindly gave her permission to use some of the figures from her stereotactic atlas of the human thalamus and basal ganglia (Morel 2007). Several pictures on gross anatomy were kindly provided by Robert Bartoš (Neurosurgical Clinic, Masaryk Hospital, Ústí nad Labem, Czech Republic) and Ondrĕj Naňka (Department of Anatomy, First Medical Faculty, Charles University Prague).

For eponyms, Dobson (1962) is followed in general. More extensive sources such as Pagel (1901), Dumesmil and Bonnet-Roy (1947), Fischer (1962), and Hübotter (1962), the third edi-tion of Gurtl, Wernich, and Hirsch’s 1883 original “Biographisches Lexikon,” Haymaker and Schiller (1968), Shepherd (1991), Clarke and O’Malley (1996), and Swanson (2014) were available for consultation. For Histology, Dhom (2001) is a good source. Alessandro Riva (Cagliari, Italy) was of great help in finding data on certain remarkable persons in (neuro)anatomy. For the eponyms, in general the nonpossessive form is used.

Nijmegen, The Netherlands Hans J. ten Donkelaar Prague, Czech Republic David Kachlík Seattle, WA, USA R. Shane Tubbs

References

Büttner-Ennever JA, Horn AKE (eds) (2014) Olszewski and Baxter: cytoarchitecture of the human brainstem, 3rd ed. Karger, Basel

Clarke E, O’Malley CD (1996) The human brain and spinal cord, 2nd ed. Norman Publishing, San Francisco, CA

Dhom G (2001) Geschichte der Histopathologie. Springer, Berlin-Heidelberg-New YorkDobson J (1962) Anatomical Eponyms, 2nd ed. Livingstone, Edinburgh-LondonDumesmil R, Bonnet-Roy F (1947) Les médecins célèbres. Masson, ParisFIPAT (2017a) Terminologia Embryologica, 2nd ed. FIPAT.library.dal.ca. Federative Inter-

national Programme for Anatomical Terminology

Preface

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FIPAT (2017b) Terminologia Neuroanatomica. FIPAT.library.dal.ca. Federative International Programme for Anatomical Terminology

Fischer I (1962) Biographisches Lexikon der hervorragenden Ärzte der letzten 50 Jahre, 3rd ed, Bd 1 u. 2. Urban & Schwarzenberg, Munich-Berlin

Geneser F (1986) Textbook of Histology. Munksgaard, Copenhagen; recent Danish edition: Brüel A, Christensen EI, Tranum-Jensen J, Qvortrup K, Geneser F (2012) Genesers his-tologi. Munksgaard, Copenhagen

Haymaker W, Schiller F, eds (1968) The founders of neurology. One hundred and forty-six biographical sketches by eighty-eight authors, 2nd ed. Thomas, Springfield, IL

Hirsch MC (2000) Dictionary of human neuroanatomy. Springer, Berlin-HeidelbergHübotter F, Hrsg (1962) Gurtl, Wernich and Hirsch’s Biographisches Lexikon der hervorra-

genden Ärzte aller Zeiten und Völker, 3rd ed, Bd 1-5 u. Ergänzungsbd. Urban & Schwarzenberg, Munich-Berlin

Jelgersma G (1931) Atlas Anatomicum Cerebri Humani. Scheltema and Holkema, AmsterdamKrstić RV (1984) Illustrated encyclopedia of human histology. Springer, Berlin-Heidelberg-

New York-TokyoKrstić RV (1988) Die Gewebe des Menschen und der Säugetiere, 2nd ed. Springer, Berlin-

Heidelberg- New YorkLockard I (1977) Desk reference for neuroanatomy. A guide to essential terms. Springer,

New York-Heidelberg-BerlinMeyer G (2016) Histology: http://histology-online.comMorel A (2007) Stereotactic atlas of the human thalamus and basal ganglia. Informa Healthcare,

New York, LondonPagel JC (1901) Biographisches Lexikon hervorragender Ärzte des neunzehnten Jahrhunderts.

Urban & Schwarzenberg, Berlin-ViennaPuelles L (2013) Plan of the developing vertebrate nervous system. Relating embryology to the

adult nervous system. In: Rakic P, Rubinstein JLR, eds, Comprehensive developmental neuroscience. Elsevier, New York, pp 187–209

Shepherd GM (1991) Foundations of the neuron doctrine. Oxford University Press, New YorkSwanson LW (2014) Neuroanatomical terminology. Oxford University Press, New Yorkten Donkelaar HJ (2011) Clinical neuroanatomy. Brain circuitry and its disorders. Springer,

Heidelberg-Dordrecht-London-New Yorkten Donkelaar HJ, Oostra R-J, eds (2014) Klinische anatomie en embryologie, 4th ed. Reed

Business Education, Amsterdam (in Dutch)ten Donkelaar HJ, Lammens M, Hori A (2006) Clinical neuroembryology. Development and

developmental disorders of the human central nervous system. Springer, Berlin- Heidelberg- New York

ten Donkelaar HJ, Lammens M, Hori A (2014) Clinical neuroembryology. Development and developmental disorders of the human central nervous system, 2nd ed. Springer, Heidelberg- New York-Dordrecht-London

ten Donkelaar HJ, Broman J, Neumann PE, Puelles L, Riva A, Tubbs RS, Kachlik D (2017) Towards a Terminologia Neuroanatomica. Clin Anat 30:145–155

Terminologia Anatomica (1998) International anatomical terminology. FCAT, Thieme, Stuttgart

Terminologia Histologica (2008) International histological terminology. FCAT, Lippincott, Wolters-Kluwer, Philadelphia, PA

Preface

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David Fisher810 Saulter Road, Birmingham, AL 35200, USA

Ad Gruter, Ereprijs 3, 3434 CN Nieuwegein, The Netherlands

Medical Illustrators

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Contents

A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

E . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153

F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181

G . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197

H . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215

I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237

J, K . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 255

L . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257

M . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 279

N . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 299

O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 313

P . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 329

Q . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 369

R . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 371

S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 397

T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 441

U . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 465

V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 469

W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 487

X, Y, Z . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 489

xiii

Robert  H.  Baud, Ph.D. Service of Medical Informatics, University Hospitals of Geneva, Geneva, Switzerland

Axel  Brehmer, M.D., Ph.D. Institute of Anatomy, University of Erlangen-Nuremberg, Erlangen, Germany

Jonas  Broman, Ph.D. Department of Clinical and Experimental Medicine, Division of Neurobiology, University of Linköping, Linköping, Sweden

Jean  A.  Büttner-Ennever, Ph.D. Department of Neuroanatomy, Faculty of Medicine, Ludwig-Maximilian-University, Munich, Germany

Matthew Carlson, M.D. Department of Otolaryngology, Mayo Clinic, Rochester, MN, USA

Marco Catani, M.D. Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, King’s College London, Strand, London, UK

Andras  Csillag, M.D., Ph.D. Department of Anatomy, Histology and Embryology, Semmelweis University, Budapest, Hungary

Anja K.E. Horn-Bochtler, Ph.D. Department of Anatomy and Cell Biology I, Faculty of Medicine, Ludwig-Maximilian-University, Munich, Germany

Ricardo Insausti, M.D., Ph.D. Department of Anatomy, Faculty of Medicine, Universidad Castilla-La Mancha, Albacete, Spain

Geoffrey Meyer, Ph.D. School of Human Sciences, University of Western Australia, Perth, WA, Australia

Veronika Němcová, M.D., Ph.D. Department of Anatomy, First Faculty of Medicine, Charles University, Prague, Czech Republic

Luis Puelles, M.D., Ph.D. Department of Human Anatomy and Psychobiology, Faculty of Medicine, University of Murcia, Murcia, Spain

Clifford B. Saper, M.D., Ph.D. Department of Neurology, Harvard University, Boston, MA, USA

Gulgun Sengul, M.D., Ph.D. Department of Anatomy, Ege University School of Medicine, Izmir, Turkey

Contributors

xv

als Anterolateral systemAmb Ambiguus nucleusAp Area postremaArc Arcuate nucleusbc, BC Brachium conjunctivumCI Inferior colliculusCod Dorsal cochlear nucleusCov Ventral cochlear nucleuscp Cerebral peduncleCS Superior colliculusCs Central superior nucleuscsp Corticospinal tractctt Central tegmental tractCun Cuneate nucleusCune External cuneate nucleusDAN Dorsal acoustic nucleusdbc Decussation of brachium conjunctivumdlf Dorsal longitudinal fasciculusdsct Dorsal spinocerebellar tractFl FlocculusGr Gracile nucleusI Inferior vestibular nucleusIc Intercalated nucleusicp Inferior cerebellar peduncleICO Intercollicular nucleusIO Inferior olivary complexKF Kölliker-Fuse nucleusL Lateral vestibular nucleusLc Locus coeruleusll Lateral lemniscusMGB Medial geniculate bodyml, ML Medial lemniscusMRF Mesencephalic reticular formationmrV Motor root of trigeminal nerveMV Medial vestibular nucleusNRTP Reticulotegmental nucleusnIII Oculomotor nervenIV Trochlear nervenV Trigeminal nervenVII Facial nervenVIII Vestibulocochlear nervenX Vagus nerve

Abbreviations of Brain Stem

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nXII Hypoglossal nerveOv Oval nucleusPAG Periaqueductal grayPBG Parabigeminal nucleusPbl Lateral parabrachial nucleusPbm Medial parabrachial nucleuspc Pontocerebellar fibersPPN Pedunculopontine tegmental nucleusPre Prepositus nucleusRd Raphe dorsalis nucleusRl Lateral reticular nucleusRm Raphe magnus nucleusRob Raphe obscurus nucleusRp Raphe pallidus nucleusRub Red nucleusrusp Rubrospinal tractSN Substantia nigraSn Supraspinal nucleusSol Solitary nucleussrV Sensory root of trigeminal nerveSV Superior vestibular nucleustsp Tectospinal tractvsct Ventral spinocerebellar tractVTA Ventral tegmental areaIV Trochlear nucleusVc Caudal subnucleus of spinal trigeminal nucleusVi Interpolar subnucleus of spinal trigeminal nucleusVm Motor trigeminal nucleusVme Mesencephalic nucleus of trigeminal nerveVo Oral subnucleus of spinal trigeminal nucleusVpr Principal sensory trigeminal nucleusVsp Spinal trigeminal nucleusVI Abducens nucleusVII Facial nucleusXdm Dorsal motor nucleus of vagus nerveXII Hypoglossal nucleus1 Posterior or dorsal trigeminothalamic tract2 Anterior or ventral trigeminothalamic tract

Abbreviations of Brain Stem

xvii

User Guide

The Illustrated TNA includes an alphabetical list of English official terms and synonyms with the official Latin terms and synonyms from the TNA. With regard to the entries, the name of the item in standardized English is given, followed by synonyms and the official TNA Latin term, Latin synonyms and eponyms, a short description and in many cases one or more illustra-tions. Throughout the book, for neurons the Brain Architecture Management System (BAMS; Bota M, Swanson LW 2007 Brain Res Rev 56:79–88) is used including sensory neurons, interneurons (short and long) and motoneurons. The short or local circuit interneurons are subdivided into excitatory and inhibitory interneurons. The long interneurons comprise the interneurons that are usually described as projection, commissural and association neurons. For the white matter tracts, the Foundation Model of Connectivity (FMC; Swanson LW, Bota M 2010 Proc Natl Acad Sci USA 107:20610–20617) is followed including (a) central roots for the cranial and spinal nerve roots within the CNS; (b) intrinsic tracts, remaining within a cer-tain component of the CNS, such as the spinal cord; (c) commissural connections; and (d) long tracts divided into ascending and descending tracts.

To facilitate the use of illustrations, certain entries such as the gyri or sulci of the cerebral cortex are presented together with extensive cross-references. Terms that form part of a certain structure (such as the amygdaloid body, the thalamus and the hypothalamus) are listed under that structure. Similarly, the subarachnoid cisterns are discussed under the heading Cisterns. Segments and branches of arteries are discussed under the main artery, for example the A1-A5 segments under the anterior cerebral artery. Most nerves can be found following their origin from the brachial, cervical and lumbosacral plexuses. However, the major nerves of the limbs are discussed separately as are the cranial nerves. Nuclei can be found by their English name or under Nuclei by their eponym.

References to sources are usually included in the descriptions of the various terms or the legends of their figures. Major sources can be found in the literature in the Preface.

Illustrated TNA, User Guide

1© Springer International Publishing AG, part of Springer Nature 2018H. J. ten Donkelaar et al., An Illustrated Terminologia Neuroanatomica, https://doi.org/10.1007/978-3-319-64789-0_1

Chapter A

A1–A16 cell groups: The aminergic (dopaminergic and noradrenergic or norepinephric) cell groups A1–A11 (TNA Latin: Cellulae aminergicae) are found in the brain stem (Fig. A1; the A3 cell group of rodents is not present in the human brain), A12–A15 in the prethalamus, the hypothalamus and the preoptic area (see Spencer S, et  al. 1985 Brain Res 328:73–80; Tillet Y 1994 Catecholaminergic neuronal sys-tems in the diencephalon of mammals. In: Smeets WJAJ, Reiner A, eds, Phylogeny and Development of Catecholamine Systems in the CNS of Vertebrates. Cambridge University Press, Cambridge), and A16 in the olfactory bulb. For English and Latin terms and brief descriptions, see Table A1.

A1–A5 segments, see Anterior cerebral arteryA-fibers: The A-fibers are the myelinated fibers of

peripheral nerves and can be divided into (Gandevia SC, Burke D 2004 Peripheral motor system. In: Paxinos G, ed, The Human Nervous System, 2nd ed. Elsevier, Amsterdam, pp 113–133): (1) Aα-fibers: motor fibers innervating extra-fusal muscle fibers with conduction velocities of up to 120 m/s; (2) Aβ-fibers: sensory fibers for touch with conduction velocities of 30–100 m/s; (3) Aγ-fibers: motor fibers inner-vating intrafusal muscle fibers with conduction velocities of less than 25–30 m/s; (4) Aδ-fibers: sensory fibers for crude touch, pressure and temperature with conduction velocities of 4–30 m/s. The sensory fibers from the muscle spindles and Golgi tendon organs are categorized as type I–IV fibers.

A-zone: The A-zone (TNA Latin: Zona A) is the most medial sagittal zone of Purkinje cells projecting to the fasti-gial nucleus; see Cerebellum, Longitudinal zones for illustration.

Abdominal aortic plexus, see Abdominal plexusesAbdominal plexuses: The abdominal plexuses (TNA

Latin: Plexus abdominales; Fig. A2) are a group of visceral plexuses found retroperitoneally close to the arteries. They are composed of efferent sympathetic and parasympathetic fibers as well as of afferent viscerosensory fibers. The fol-lowing plexuses can be distinguished:

(1) The abdominal aortic or intermesenteric plexus (TNA Latin: Plexus aorticus abdominalis; Latin synonym:

Plexus intermesentericus) is found on the ventral and lateral sides of the abdominal aorta between the origins of the supe-rior and inferior mesenteric arteries; it is continuous crani-ally with the celiac plexus and caudally with the superior hypogastric and common iliac plexuses, and receives fibers from the first and second lumbar splanchnic nerves.

(2) The celiac or coeliac plexus (TNA Latin: Plexus coeli-acus) is the largest visceral plexus found on the ventrolateral side of the abdominal aorta at the level of origin of the celiac trunk and is also known as the solar plexus. It comprises the paired celiac or coeliac ganglion (TNA Latin: Ganglion coe-liacum) and the paired aorticorenal ganglia (TNA Latin: Ganglia aorticorenalia), which form a dense network of inter-connecting nerve fibers. Their sympathetic fibers pass via the greater, lesser and least thoracic splanchnic nerves, and para-sympathetic fibers via the posterior trunk of the vagus nerve. Viscerosensory afferent fibers carrying nociceptive impulses from the abdominal part of the esophagus down to the trans-verse colon, the omenta and the mesenteries, the kidneys and the suprarenal glands, pass through the celiac plexus on their way to the spinal cord. The celiac plexus gives rise to the fol-lowing plexuses to various viscera: (a) the hepatic plexus (TNA Latin: Plexus hepaticus), accompanying the common hepatic artery and supplying the liver, the gallbladder, the superior part of the duodenum and the head of the pancreas; (b) the splenic plexus (TNA Latin: Plexus splenicus; Latin synonym: Plexus lienalis), accompanying the splenic artery and supplying the spleen, the fundus of the stomach and body and the tail of the pancreas; (c) gastric plexuses (TNA Latin: Plexus gastrici), accompanying the gastric arteries along the lesser curvature of the stomach, and the gastroomental arter-ies along the greater curvature to supply the stomach; and (d) the pancreatic plexus (TNA Latin: Plexus pancreaticus), accompanying the arteries supplying the pancreas.

(3) The inferior mesenteric plexus (TNA Latin: Plexus mesentericus inferior) is a caudal continuation of the abdominal aortic plexus and is found around the origin of the inferior mesenteric artery. It contains the inferior mesen-teric ganglion (TNA Latin: Ganglion mesentericum inferius)

2

and accompanies the artery within the mesocolon to a small left part of the transverse colon, to the descending colon and the sigmoid colon. It continues into the lesser pelvis as the superior rectal plexus (TNA Latin: Plexus rectalis superior) along the superior rectal artery to the rectal ampulla; see also Pelvic plexuses.

(4) In females, the ovarian plexus (TNA Latin: Plexus ovaricus) descends within the suspensory ligament of the

ovary accompanying the ovarian artery to supply the ovary, the uterine tube and the fundus of the uterus.

(5) The phrenic plexus (TNA Latin: Plexus phrenicus) originates from the superior part of the celiac ganglion, accompanies the inferior phrenic artery to the diaphragm and receives one or two branches from the phrenic nerve.

(6) The dense renal plexus (TNA Latin: Plexus renalis) arises from the celiac and aorticorenal ganglia and accompa-

nIII

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Fig. A1 Neuromelanin-staining of the noradrenergic cell groups A1–A10  in the human brain stem mapped on horizontal sections from a rostral to f caudal (after Duvernoy HM 1995 The Human Brain Stem

and Cerebellum. Springer, Vienna, New York, and data by Bogerts B 1981 J Comp Neurol 197:63–80, and Saper CB, Petito CK 1982 Brain 105:87–101). For abbreviations see List of abbreviations of brain stem

Chapter A

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nies the renal artery. The renal plexus contains several renal ganglia (TNA Latin: Ganglia renalia) and its fibers wind around the arterial branches of the renal artery to supply the glomeruli and tubules of the kidney.

(7) The suprarenal plexus (TNA Latin: Plexus suprarena-lis) is formed by branches from the celiac plexus and sup-plies mainly the medulla of the suprarenal gland.

(8) The superior hypogastric plexus (TNA Latin: Plexus hypogastricus superior) forms the caudal part of the abdomi-nal aortic plexus and continues into the lesser pelvis; see also Pelvic plexuses.

(9) The superior mesenteric plexus (TNA Latin: Plexus mesentericus superior) is the caudal continuation of the

celiac plexus. It is located around the origin of the superior mesenteric artery, contains the superior mesenteric gan-glion (TNA Latin: Ganglion mesentericum superius), accom-panies the branches of the artery and supplies the pancreas, the small intestine, the cecum, the vermiform appendix, the ascending colon and the major right part of the transverse colon.

(10) In males, the testicular plexus (TNA Latin: Plexus testicularis) accompanies the testicular artery, passes through the inguinal canal and supplies the testis and the epididymis.

(11) The ureteric plexus (TNA Latin: Plexus uretericus) covers and supplies the ureter. Its abdominal part receives

Table A1 Aminergic (dopaminergic and noradrenergic or norepinephric) cell groups in the CNS

English official term English synonym TNA Latin term Latin synonym NotesA1, A2: Noradrenergic or norepinephric cells in medulla oblongata

Noradrenergic or norepinephric cell groups A1, A2

Cellulae noradrenergicae medullae oblongatae

Cellulae noradrenergicae A1, A2

A1, A2 cell groups in rhombomeres 7–11

A4: Noradrenergic or norepinephric cells of superior cerebellar peduncle

Noradrenergic or norepinephric cell group A4

Cellulae noradrenergicae pedunculi cerebellaris superioris

Cellulae noradrenergicae A4

A4 cell group in rhombomere 1

A5: Noradrenergic or norepinephric cells in caudolateral pons

Noradrenergic or norepinephric cell group A5

Cellulae noradrenergicae pontis caudales laterales

Cellulae noradrenergicae A5

A5 cell group within retropontine domain (rhombomere 5)

A6: Caerulean nucleus Coerulean nucleus; Noradrenergic or norepinephric nucleus A6

Nucleus caeruleus Nucleus noradrenergicus A6

A6 cell group in rhombomere 1

A7: Noradrenergic or norepinephric cells in nucleus of lateral lemniscus

Noradrenergic or norepinephric cell group A7

Cellulae noradrenergicae nuclei lemnisci lateralis

Cellulae noradrenergicae A7

A7 cell group dispersed within and around the ventral nucleus of the lateral lemniscus

A8: Dopaminergic cells in retrorubral area

Dopaminergic cell group A8

Cellulae dopaminergicae retrorubrales

Cellulae dopaminergicae A8

In caudal mesencephalon

A9: Dopaminergic cells in compact part of substantia nigra

Dopaminergic cell group A9

Cellulae dopaminergicae partis compactae substantiae nigrae

Cellulae dopaminergicae A9

Isthmic, mesencephalic and prosomeric 1–3 parts

A10: Dopaminergic cells in ventral tegmental area

Dopaminergic cell group A10

Cellulae dopaminergicae areae tegmentalis ventralis

Cellulae dopaminergicae A10

Isthmic, mesencephalic and prosomeric 1–3 parts

A11: Dopaminergic cell groups of periaqueductal gray

Dopaminergic cell group A11

Cellulae dopaminergicae areae periaqueductalis

Cellulae dopaminergicae A11

A11, originally described as being in the posterior hypothalamus has been renamed

A12: Dopaminergic cells of arcuate nucleus

Dopaminergic cell group A12

Cellulae dopaminergicae nuclei arcuati

Cellulae dopaminergicae A12

In terminal hypothalamus

A13: Dopaminergic cells of zona incerta

Dopaminergic cell group A13

Cellulae dopaminergicae zonae incertae

Cellulae dopaminergicae A13

In dorsomedial hypothalamus and zona incerta

A14: Dopaminergic cells of anterior area of hypothalamus

Dopaminergic cell group A14

Cellulae dopaminergicae areae anterioris hypothalamicae

Cellulae dopaminergicae A14

Especially abundant in the paraventricular nucleus

A15: Dopaminergic cells of preoptic area

Dopaminergic cell group A15

Cellulae dopaminergicae areae preopticae

Cellulae dopaminergicae A15

Dorsal and ventral subdivisions (Spencer S, et al. 1985 Brain Res 328:73–80)

A16: Dopaminergic cells in olfactory bulb

Dopaminergic cell group A16

Cellulae dopaminergicae bulbi olfactorii

Cellulae dopaminergicae A16

Periglomerular cells (Kosaka K, Kosaka K 2005 Anat Sci Int 80:80–90)

Chapter A

4

fibers from the renal and abdominal aortic plexuses and its pelvic part from the superior hypogastric plexus and the hypogastric nerve. The intramural part of the ureter receives fibers from the inferior hypogastric plexus.

Aberrant pyramidal fibers, see Pyramidal tractAbducens nerve (VI): The abducens nerve or cranial

nerve VI (TNA Latin: Nervus abducens; Latin synonym: Nervus cranialis VI) is a thin somatomotor nerve, which leaves the brain stem in the bulbopontine sulcus and passes through the abducens nerve canal, the cavernous sinus and the superior orbital fissure to the orbit (Fig. A3). Here, it inner-vates the lateral rectus muscle; see also Extraocular muscles.

Abducens nerve canal: The fibroosseous abducens nerve canal (TNA Latin: Canalis nervi abducentis; eponym: canal of Dorello) is found at the apex of the petrous part of the temporal bone, where the abducens nerve can be easily damaged in cranial trauma, and is cranially bound by the pet-roclinoid or petrosphenoid ligament of Gruber (Fig. A4).

Abducens nucleus: The abducens nucleus (TNA Latin: Nucleus nervi abducentis; Latin synonym: Nervus cranialis VI) lies in the pontomedullary part of the brain stem (rhom-bomere 5) and together with the internal genu of the facial nerve forms a dorsal protrusion in the fourth ventricle, known as the facial colliculus (Fig. A5). The abducens nucleus contains motoneurons innervating the lateral rectus muscle, internuclear neurons and neurons with projections to the cerebellum. Axons of the internuclear abducens neu-rons ascend in the contralateral medial longitudinal fascicu-lus and terminate in the medial rectus subnucleus of the oculomotor nerve. The third component forms part of the cell groups of the paramedian tract (PMT Cell group 4b), which innervate the flocculus, the paraflocculus and the ver-mis (Büttner-Ennever JA, Horn AKE 1996 Ann NY Acad Sci 781:532–540).

Accessory cuneate nucleus: The accessory or external cuneate nucleus (TNA Latin: Nucleus cuneatus accessorius; Latin synonym: Nucleus cuneatus externus; eponym: nucleus of von Monakow) is an elongated nucleus lateral to the cuneate nucleus (Fig. A6). It is composed of secondary somatosensory neurons, which convey proprioceptive sig-nals from the upper limb and neck to the cerebellum (the cuneocerebellar tract; TNA Latin: Tractus cuneocerebel-laris; Cooke JD, et  al. 1971 Exp Brain Res 13:339–358; Hummelsheim H, et al. 1985 Neuroscience 16:979–987; see Spinocerebellar tracts for illustration) and the thalamus (the kinetic component of proprioception; Boivie J, et  al. 1975 Neurosci Lett 1:3–8). It is the homologue of the Clarke- Stilling nucleus of the thoracic spinal cord, which receives proprioceptive information from the lower part of the body.

Accessory facial nucleus: Synonym for the retrofacial nucleus; see Retrofacial nucleus.

Accessory intercostobrachial nerve: The accessory intercostobrachial nerve (TNA Latin: Nervus intercosto-brachialis accessorius) is an inconstant lateral cutaneous branch of the third intercostal nerve piercing the intercostal space in the midaxillary line, merging with the medial bra-chial cutaneous nerve and supplying the skin of the axilla.

Accessory medullary lamina: The accessory medul-lary lamina (TNA Latin: Lamina medullaris accessoria) divides the medial segment of the globus pallidus into lateral and medial parts; see Basal nuclei for illustration.

Accessory nerve (XI): The accessory nerve or cranial nerve XI (TNA Latin: Nervus accessorius; Latin synonym: Nervus cranialis XI; eponym: nerve of Willis) is usually described as having two roots, a cranial (TNA Latin: Radix

1

32

4

56

7

8

910

Fig. A2 Diagram of the abdominal plexuses (after ten Donkelaar and Oostra 2014): 1 greater thoracic splanchnic nerve, 2 lesser thoracic splanchnic nerve, 3 sympathetic trunk, 4 celiac ganglion, 5 superior mesenteric ganglion, 6 aorticorenal ganglion, 7 inferior mesenteric gan-glion, 8 superior hypogastric plexus, 9 right hypogastric nerve, 10 left hypogastric nerve

Chapter A

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mlals

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cttRm

VInVII

MV

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baFig. A3 (a) MRI, showing the exit of the abducens nerve and (b) corresponding horizontal section through the human brain stem at the abducens (VI) nucleus (from ten Donkelaar 2011). For other abbreviations see List of abbreviations of brain stem

Anterior petroclinoid fold

Posterior petroclinoid fold

Basilar venous plexusPetrous ridge

Abducens nerve

Petroclinoid ligament

Posterior clinoid process

Anterior clinoid process

Oculomotor nerve

Fig. A4 The abducens nerve canal

ml

als

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lsII

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Fig. A5 The abducens nucleus (VI; after Duvervoy HM 1995 The Human Brain Stem and Cerebellum. Springer, Vienna, New York). For other abbreviations see List of abbreviations of brain stem

csp

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Fig. A6 The accessory or external cuneate nucleus (Cune; after Duvernoy HM 1995 The Human Brain Stem and Cerebellum. Springer, Vienna, New York). For other abbreviations see List of abbreviations of brain stem

Chapter A

6

cranialis) and a spinal (TNA Latin: Radix spinalis), which fuse in the jugular foramen to form a single and short nerve trunk (TNA Latin: Truncus nervi accessorii; Fig. A7; Tubbs RS, et al. 2014 Clin Anat 27:102–107). This trunk gives rise to an internal or vagal communicating branch (TNA Latin: Ramus internus; Latin synonym: Ramus communicans vaga-lis), joining the vagus, and an external branch or spinal accessory nerve (TNA Latin: Ramus externus; Latin syn­onym: Nervus accessorius spinalis), representing the acces-sory nerve proper. The latter is a purely somatomotor nerve and supplies the sternocleidomastoid and trapezius muscles through muscular branches (TNA Latin: Rami musculares): the sternocleidomastoid and trapezius branches (TNA Latin: Ramus sternocleidomastoideus and Ramus trapezius). The cranial fibers arise mainly from the nucleus ambiguus, form the internal ramus, and may be viewed as an aberrant vagus rootlet. These fibers innervate laryngeal muscles.

Accessory nuclei of oculomotor nerve: The accessory nuclei of the oculomotor nerve (TNA Latin: Nuclei acces-sorii nervi oculomotorii) include (Fig. A8; see Horn AK, et al. 2008 J Comp Neurol 507:1317–1335; Büttner-Ennever JA, Horn AKE 2014 Olszewski and Baxter: Cytoarchitecture of the Human Brainstem, 3rd ed. Karger, Basel): (1) the pre-ganglionic part (TNA Latin: Pars preganglionica), the cyto-architectonically defined central group, traditionally considered as the location of preganglionic neurons for the parasympathetic ciliary ganglion in the Edinger-Westphal nucleus (EWpg); eponym: nucleus of Edinger-Westphal; (2) the nonganglionic, projecting part (TNA Latin: Pars

nonganglionica), the lateral nonganglionic part of the Edinger-Westphal nucleus, containing urocortin-positive neurons with central projections to the lateral septum, raphe nuclei and the spinal cord (EWcp); eponym: nucleus of Edinger-Westphal; (3) the anterior medial or ventral medial nucleus (TNA Latin: Nucleus anteromedialis), also illustrated as medial accessory oculomotor nucleus (Paxinos G, Huang X-F 1995 Atlas of the Human Brainstem. Academic Press, San Diego, CA).

Accessory nucleus of optic tract, see PretectumAccessory obturator nerve: The accessory obturator

nerve (TNA Latin: Nervus obturatorius accessorius) is an inconstant branch of the anterior part of the lumbar plexus (L3–L4), present in about 10% of cases. It arises behind the psoas major muscle, penetrates its belly and descends along its medial border to the pectineus muscle. Here, it ramifies and supplies the pectineus muscle and the hip joint, and often sends a communicating branch to the anterior branch of the obturator nerve.

Accessory paraflocculus: The accessory paraflocculus (TNA Latin: Paraflocculus accessorius) forms part of lobule HIX of the posterior part of the cerebellar hemisphere; see also Cerebellum, Subdivision.

Accessory phrenic nerve: The accessory phrenic nerve (TNA Latin: Nervus phrenicus accessorius) is an inconstant branch of the brachial plexus, which usually joins the phrenic nerve near the first rib.

Accessory trigeminal nucleus: Synonym for the retrotri-geminal nucleus; see Retrotrigeminal nucleus.

Internal Jugular Vein

CN IX

CN X InternalBranches

CranialRoots

CN XI

SpinalRoots

ExternalBranch

Fig. A7 Schematic drawing showing the components of the accessory nerve and its surrounding neurovascular structures (from Tubbs RS, et al. 2014 Clin Anat 27:102–107; with permission)

Chapter A

7

a

c d e

b

III

CCNcen

ven MLFMLF

EWcpEWpg

EWcp EWcp

EWcp

EWcp

EWcp

dl

dldm

dm

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NPcen

ven

ven

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EWpg

dl

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lat

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dl

Fig. A8 (a–e) Transverse sections from caudal to rostral through dif-ferent levels of the oculomotor complex (from Büttner-Ennever JA, Horn AKE 2014 Olszewski and Baxter: Cytoarchitecture of the Human Brainstem, 3rd ed. Karger, Basel; used with permission from Karger). CCN central caudal nucleus, cen, dl, dm central, dorsolateral and dorso-

medial subnuclei of III, EWcp Edinger-Westphal nucleus, centrally pro-jecting (urocortin) neurons, EWpg Edinger-Westphal nucleus, preganglionic neurons, III oculomotor nucleus, lat lateral subnucleus of III, MLF medial longitudinal fasciculus, NP nucleus of Perlia (see Interoculomotor nucleus), ven ventral subnucleus of III

Accessory visual structures: The accessory visual structures (TNA Latin: Structurae oculi accessoriae) include: (1) the orbital fasciae; (2) the extraocular muscles; (3) the eyebrows; (4) the eyelids; (5) the conjunctiva; and (6) the lacrimal apparatus.

Accumbens nucleus: The nucleus accumbens (TNA Latin: Nucleus accumbens) was described in 1872 by Theodor Meynert as a nucleus leaning against the septum (his Nucleus accumbens septi; see Meynert). The nucleus contains several groups of neurons, many of which are part

Chapter A

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of the basal ganglia, but other, possibly limbic, neuronal groups also occur. The nucleus accumbens has numerous connections typical for the ventral striatum as well as for the extended amygdala. Its neurons are activated in situations involving reward and punishment, integrating certain cogni-tive aspects of the situation with emotional components. This brain region has been implicated in addictive behavior. As in rodents, the human nucleus accumbens (Fig. A9) is com-posed of an outer medial part or shell region (TNA Latin: Pars medialis; Latin synonym: Regio tegens) and a central part or core region (TNA Latin: Pars centralis; Latin syn­onym: Regio nuclearis), which differ greatly in their projec-tions as well as immunohistochemically (Heimer L, et  al. 1997 J Neuropsychiatry Clin Neurosci 9:354–381). The core and shell dichotomy as originally described in rodents by Laszlo Záborszky (Záborszky L, et  al. 1985 Neuroscience 14:427–453) has been confirmed for the human brain with a medial, low calbindin-immunoreactive and high calretinin- immunoreactive compartment, representing the shell, and a lateral, high calbindin-immunoreactive compartment, repre-senting the core (Morel A, et  al. 2002  J Comp Neurol 443:86–103). With diffusion tractography (Baliki MN, et al. 2013 J Neurosci 33:16383–16393), projections from the lat-erorostral core and mediocaudal shell were demonstrated to prefrontal cortical and limbic subcortical structures.

Acoustic nuclei, see Auditory nucleiAcoustic projections, see Auditory projectionsAcoustic radiation: The classic studies in the human

brain located the proximal part of the acoustic radiation (TNA Latin: Radiatio acustica) just caudal to the thalamus, where it originates from the medial geniculate body, then passes through the sublenticular limb of the internal capsule to curve around the inferior part of the circular sulcus of the insula before reaching the transverse temporal gyri of Heschl. Rademacher and co-workers showed the stereotaxic local-ization, intersubject variability and interhemispheric differ-ences of the human acoustic radiation (Fig. A10; Rademacher J, et  al. 2002 Neuroimage 17:142–160). They showed that the location of the acoustic radiation varies considerably between individuals and hemispheres.

Acoustic tubercle: The acoustic tubercle (TNA Latin: Tuberculum acusticum) is a small swelling on the dorsolat-eral surface of the medulla overlying the cochlear nuclei; see Fourth ventricle for illustration.

Acroterminal domain: The acroterminal domain is the most rostral part of the secondary prosencephalon, from which the optic vesicles, the median eminence and the neu-rohypophysis arise (Puelles L, et al. 2012 Hypothalamus. In: Watson C, Paxinos G, Puelles L, eds, The Mouse Nervous System. Elsevier, Amsterdam, pp 221–312).

Adamkiewicz, Albert Wojciech (1850–1921): Polish pathologist noted for the first extensive study on the blood vessels of the spinal cord (1881, 1882; see Great radicular

artery of Adamkiewicz. References: Die Blutgefässe des menschlichen Rückenmarks. I.  Teil: Die Gefässe der Rückenmarkssubstanz. Sitzungsber Kais Akad Wiss Wien 1881, 84. Bd; II.  Teil: Die Gefässe der Rückenmark­soberfläche. Ibid. 1882, 85. Bd.

Adenohypophysis, see Pituitary glandAdhesio interthalamica: The interthalamic adhesion

or massa intermedia (TNA Latin: Adhesio interthalamica; Latin synonym: Massa intermedia) is a midline structure interconnecting the two thalami across the third ventricle. Old synonyms: middle commissure, soft commissure.

Adrenergic cell groups, see C1, C2 Cell groups‘Affenspalte’: On the lateral surface of the cerebral hemi-

sphere, the parietooccipital sulcus (TNA Latin: Sulcus pari-etooccipitalis) is more pronounced in monkeys and, therefore, known as ‘Affenspalte’.

Afferent: Incoming, conducting towards.

Fig. A9 The accumbens nucleus shown in a Weigert-stained coronal section of the cerebrum from the Jelgersma Collection (from ten Donkelaar 2011). The accumbens nucleus is found immediately below the lateral ventricle. The darkly stained wing-shaped band below the accumbens is the diagonal band of Broca. The part directly above this band is the medial shell region of the accumbens surrounding the cen-tral core

Chapter A

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Afferent neuron, see Neuron, AfferentAfferent peripheral nerve fibers: The afferent periph-

eral nerve fibers (TNA Latin: Neurofibrae periphericae afferentes) arise from receptors and transmit sensory stimuli via the spinal nerves to the spinal cord or via the cranial nerves to the brain stem. The sensory axons in peripheral nerves can be subdivided into myelinated and unmyelinated classes (Erlanger J, Gasser HS 1937 Electrical Signs of Nervous Activity. University of Pennsylvania Press, Philadelphia, PA; Willis WD, Coggeshall RE 1991 Sensory Mechanisms of the Spinal Cord, 2nd ed. Plenum, New York; Mountcastle VB 2005 The Sensory Hand. Harvard University Press, Cambridge, MA): two broad classes of myelinated cutaneous and visceral afferent fibers (the Aαβ- or Aβ- and the Aδ-fibers with conduction velocities of 30–100 m/s and 4–30 m/s, respectively), and the unmyelinated C-fibers with conduction velocities less than 2.5 m/s. The muscle and joint nerves form three classes of myelinated axons (Lloyd DPC, Chang HT 1948 J Neurophysiol 11:199–208): groups I-III with conduction velocities of 72–120  m/s, 24–71  m/s and 6–23  m/s, respectively. The unmyelinated IV axons have conduction velocities less than 2.5 m/s.

Afferent synapse, see SynapsesAganglionic plexus of mucosa, see Enteric plexusesAganglionic plexus of musculus mucosae, see Enteric

plexusesAganglionic plexus of serosa, see Enteric plexusesAgranular insular cortex, see InsulaAgranular isocortex, see Isocortex, SubdivisionAla cinerea: Old term for the vagal trigone.Alar plate: The alar plate (TE2 Latin: Lamina alaris) is one

of the four longitudinal zones of the neural tube (Fig. A11). In the spinal cord, the alar plate and the incoming posterior or dor-sal roots form the afferent or sensory part, whereas the basal plate (TE2 Latin: Lamina basalis) and its exiting anterior or

ventral roots form the efferent or motor part (see Basal plate). This situation is also found in the brain stem. Gene expression data showed that also in the prosencephalon alar and basal parts can be distinguished (Puelles L 2013 Plan of the developing vertebrate nervous system. Relating embryology to the adult nervous system. In: Rakic P, Rubinstein JLR, eds, Comprehensive Developmental Neuroscience. Elsevier, New York, pp 187–209; Puelles L, et al. 2013 Trends Neurosci 36:570–578). The entire telencephalon, pallium and subpallium, appears to be of alar origin, whereas the hypothalamus and the diencephalon have both alar and basal parts (see Prosomeres and Prosomeric model for further discussion). Derivatives of the alar plate are dis-cussed under the various parts of the CNS.

Alba: Pertaining to the white matter of the brain and spi-nal cord; see Substantia alba.

Alderman’s nerve: The auricular branch of the vagus nerve is also known as Alderman’s nerve because tradition-ally, Aldermans (Municipal magistrates in UK and US) dur-ing a gargantuan Alderman’s dinner used to stimulate their jaded appetites by dropping cold water behind the ear. This practice reflexly encouraged gastric peristalsis.

Allocortex: The three-layered allocortex (TNA Latin: Allocortex; Fig. A12) includes the olfactory cortex (the paleocortex) and the hippocampal formation (the archicor-tex) and is composed of an outer, plexiform layer, a central, compact layer, and an inner, polymorph layer (Filimonoff IN 1947 Arch Neurol Psychiatry 58:296–311; Stephan H 1975 Allocortex. Hb Mikrosk Anat, Vol 4, Part 9. Springer, Berlin- Heidelbeg- New York). These components and their layers are summarized in Table A2.

Alpha motoneuron, see MotoneuronsAlveus: The alveus (TNA Latin: Alveus) is a layer of

myelinated fibers on the ventricular surface of the hippocam-pus arising from cells in the cornu ammonis and collecting to form the fimbria; see also Hippocampus, Fiber connections.

a b

AR

OROR

AR

AR

OR

Fig. A10 The acoustic and optic radiations in coronal (a) and sagittal (b) probabilistic maps (after Rademacher J, et  al. 2002 Neuroimage 13:669–683). AR acoustic radiation; OR optic radiation

Chapter A

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Amacrine cells, see Retina, Cell typesAmbient gyrus: The ambient gyrus (TNA Latin: Gyrus

ambiens) forms part of the uncus. It faces the ambient cis-tern; see Cerebral cortex, Gyri, for illustration.

Ambient cistern, see CisternsAmbiguus nucleus: The nucleus ambiguus or ventral

nucleus of the vagus nerve (TNA Latin: Nucleus ambig-uus) is the branchiomotor nucleus of the glossopharyngeal and vagus nerves (Fig. A13). It is viscerotopically orga-nized and innervates the striated muscles of the pharynx, the larynx and the esophagus (Kalia M, Mesulam M-M 1980a, b J Comp Neurol 193:435–465, 467–508; Holstege G, et  al. 1983 Brain Behav Evol 23:47–62); see also Branchiomotor nuclei.

Amiculum of olive: The amiculum of the olive (TNA Latin: Amiculum olivare) is the terminal part of the central tegmental tract surrounding the inferior olivary complex (see Fig. A13); see also Central tegmental tract.

Ammon’s horn, see Hippocampus properAmpulla, Membranous: The membranous ampulla

(TNA Latin: Ampulla membranacea) is a dilation at one end

CI

CS

cb

r1r2r0

r3r4 r5

r6r7 r8 r9 r10

r11p1

p2p3

hyp

tel

bpap

Fig. A11 Segmentation of the human brain (after Puelles López L, Martínez Pérez S, Martínez de la Torre M 2008 Neuroanatomía. Médica Panamericana, Buenos Aires, Madrid). The dotted line marks the sepa-ration between the alar plate derivatives (in light red) dorsally and the basal plate derivatives ventrally. cb cerebellum, CI colliculus inferior, CS colliculus superior, hyp hypothalamus, p1–p3 prosomeres, r0–r11 rhombomeres, tel telencephalon

A. Allocortex bulbi olfactorii B. Allocortex primitivus C. Periallocortex

I. Palaeocortex

II. Archicortex

III. Peripalaeocortex

IV. Periarchicortex

Bulbus olfactoriusBulbus olfactorius accessorius 1. Palaeocortex I oder Semicortex

2. Palaeocortex II oder Eupalaeocortex

Regio retrobulbarisRegio periamygdalarisTuberculum olfactoriumSeptum mit Regio periseptalisRegio diagonalis

Regio praepiriformis

SubiculumCornu ammonisFascia dentataHippocampus supracommissuralisHippocampus praecommissuralis

des Hippocampusretrocommissuralis Regio peripalaeocorticalis claustralis

Regio entohinalis mitArea perirhinalis

Area parasubicularis

mit Area subgenualis

Regio praesubicularis mit

Regio retrosplenialisRegio cingularis periarchicorticalis

Fig. A12 Medial view of the allocortex (from Stephan H 1975 Allocortex. Hb Mikrosk Anat, Vol 4, Part 9, Springer, Berlin-Heidelberg- New York). In yellow the paleocortex and peripaleocortex are shown, in

light blue the periarchicortex and in blue the archicortex (see text for further explanation)

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Table A2 Allocortex: Components with layers (based on Stephan H 1975 Allocortex.Handbuch der mikroskopischen Anatomie des Menschen, Vol 4, Teil 9. Springer, Heidelberg))

English official term English synonym TNA Latin term Latin synonym NotesPaleocortex PaleocortexOlfactory bulb Bulbus olfactoriusOlfactory nerve layer Stratum neurofibrosum Stratum

fibrosumGlomerular layer Stratum glomerulosumExternal plexiform layer Stratum plexiforme externumMitral cell layer Stratum mitraleInternal plexiform layer Stratum plexiforme internumGranular cell layer Stratum granulareRetrobulbar region Regio retrobulbaris Earlier known as Nucleus olfactorius

anterior, but mostly corticalMolecular layer Stratum moleculareDensocellular layer Stratum densocellulareMultiform layer Stratum multiformeOlfactory tubercle Tuberculum olfactorium Largely belongs to ventral striatumPiriform cortex BA51 Cortex piriformis Frontal and temporal partsMolecular layer Stratum moleculareDensocellular layer Stratum densocellulareMultiform layer Stratum multiformePeriamygdaloid area Regio periamygdaloideaMolecular layer Stratum moleculareDensocellular layer Stratum densocellulareClaustral peripaleocortical region

BA16 Regio peripaleocorticalis claustralis

Molecular layer Stratum moleculareDensocellular layer Stratum densocellulareDissecting layer Stratum dissecansMultiform layer Stratum multiformeArchicortex ArchicortexHippocampal formation Formatio hippocampiHippocampus proper Ammon’s horn Hippocampus proprius Cornu

ammonisLacunar-molecular layer Stratum moleculare et

substratum lacunosumRadiate layer Stratum radiatumPyramidal layer Stratum pyramidaleOriens layer Stratum oriensDentate gyrus Gyrus dentatusMolecular layer Stratum moleculareGranular layer Stratum granulareMultiform layer Stratum multiformeSubiculum SubiculumMolecular layer Stratum molecularePyramidal layer Stratum pyramidaleMultiform layer Stratum multiformePeriarchicortex PeriarchicortexPresubiculum PresubiculumMolecular layer Stratum moleculareExternal principal layer Stratum principale externumInternal principal layer Stratum principale internumParasubiculum ParasubiculumMolecular layer Stratum moleculareCellular layer Stratum cellulare

(continued)

Chapter A

of each semicircular duct, containing the ampullary crest; see Ear, Internal for further data and illustration.

Ampulla, Osseus: The osseous ampulla (TNA Latin: Ampulla ossea) is a part of the bony labyrinth of the internal ear and houses the membranous ampulla; see Labyrinth, Bony for further data and illustration.

Ampullary crest, see Ear, InternalAmpullary cupula, see Ear, InternalAmpullary groove, see Ear, InternalAmygdala, see Amygdaloid bodyAmygdaloid body: The amygdaloid body, amygdaloid

complex or simply amygdala (TNA Latin: Corpus amygda-loideum; Latin synonym: Complexus amygdaloideus) is a highly differentiated and heterogeneous structure located in the medial part of the temporal lobe (Fig. A14). The name amygdala is derived from the Greek word for almond to which Karl Burdach compared its macroscopical shape in a brain section (Burdach KF 1819–1826 Vom Baue und Leben des Gehirns. Dyk, Leipzig, 3 Vols). The amygdaloid body is com-posed of pallial and subpallial parts. The basolateral nuclear group and the associated olfactory amygdala, also known as cortical amygdala, form the pallial part, whereas the centro-medial nuclear group forms the subpallial part. The centro-medial amygdala forms a continuum with the bed nucleus of the stria terminalis, known as the extended amygdala (Fig. A15; Alheid GF, Heimer L 1988 Neuroscience 27:1–39).

Cell groups: The amygdaloid nuclei are placed into groups (Fig. A16), following de Olmos JS (2004 Amygdala. In: Paxinos G, Mai JK, eds: The Human Nervous System, 2nd

ed. Elsevier, Amsterdam, pp 739–868), its more recent ver-sion (Yilmazer-Hanke DM 2012 Amygdala. In: Mai JK, Paxinos G, eds, The Human Nervous System, 3rd ed. Elsevier, Amsterdam, pp 759–784), and Mai JK, Paxinos G, Voss T (2008 Atlas of the Human Brain, 3rd ed. Elsevier, Amsterdam):

(1) The basolateral nuclear group (TNA Latin: Nuclei basolaterales) forms the greater part of the amygdaloid body.

Table A2 (continued)

English official term English synonym TNA Latin term Latin synonym NotesEntorhinal cortex BA28, 34 Cortex entorhinalisMolecular layer Layer 1 Stratum moleculare Lamina 1External principal layer Stratum principale externum Cell island layer Layer 2 Stratum stellare Lamina 2 Pyramidal layer Layer 3 Stratum pyramidale Lamina 3Dissecting layer Layer 4 Lamina dissecans Lamina 4Internal principal layer Layer 5 Stratum principale internum Lamina 5 Magnocellular layer Sublayer 5a Stratum magnocellulare Sublamina 5a Parvocellular layer Sublayer 5b Stratum parvocellulare Sublamina 5b Multiform layer Sublayer 5c Stratum multiforme Sublamina 5cPerirhinal cortex BA35 Cortex perirhinalisTransentorhinal subregion Subregio transentorhinalisRetrosplenial cortex Cortex retrosplenialisEctosplenial cortex BA26 Cortex ectosplenialisGranular retrosplenial cortex

BA29 Cortex retrosplenialis granularis

Dysgranular retrosplenial cortex

BA30 Cortex retrosplenialis dysgranularis

Cingulate cortex Cortex cingularis For further subdivision, see Cingulate cortex

ArcnXII

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Fig. A13 The ambiguus nucleus (Amb; after Duvernoy HM 1995 The Human Brain Stem and Cerebellum. Springer, Vienna, New York). For further abbreviations see List of abbreviations of brain stem

12 Chapter A

13

It is profusely interconnected with the cerebral cortex and has widespread projections to the striatum. This group comprises: (a) the basolateral amygdaloid nucleus (TNA Latin: Nucleus basalis lateralis amygdalae), which occupies its central and ventral thirds and has six subnuclei (large-celled dorsal and dorsolateral, medium-celled intermediate, small- celled ven-trolateral and ventromedial, and granule-celled paralaminar); (b) the basomedial amygdaloid nucleus (TNA Latin: Nucleus basalis medialis amygdalae), earlier known as basal accessory amygdaloid nucleus, which lies under the semilu-nar gyrus and has five subnuclei (dorsomedial large-celled, dorsolateral mixed-celled, ventromedial medium-celled, ven-trolateral small-celled and caudomedial large-celled); (c) the lateral amygdaloid nucleus (TNA Latin: Nucleus lateralis amygdalae), which occupies the rostral three quarters of the amygdaloid complex, is the largest of all amygdaloid nuclei, and has five subnuclei (dorsal anterior, intermediate, ventral, dorsomedial and dorsolateral); and (d) the amygdaloclaus-

tral transition area (TNA Latin: Area transitionis amygdalo-claustralis), islands of amygdaloid cells intercalated between the ventral claustrum and the lateral amygdaloid nucleus.

(2) The centromedial nuclear group (TNA Latin: Nuclei centromediales), which comprises: (a) the central amygdaloid nucleus (TNA Latin: Nucleus centralis amygdalae), which is situated in the caudal half of the amygdala and has lateral and medial subdivisions; the central nucleus is the main output cen-ter of the amygdala; (b) the medial amygdaloid nucleus (TNA Latin: Nucleus medialis amygdalae), an elongated rostrocau-dally oriented nucleus with anterior and posterior subdivisions; (c) the intercalated amygdaloid nuclei (TNA Latin: Nuclei intercalati amygdalae); and (d) the amygdalostriatal transi-tion area (TNA Latin: Area transitionis amygdalostriatalis).

(3) The extended amygdala (TNA Latin: Amygdala extenta), which comprises: (a) the bed nucleus of the stria terminalis (TNA Latin: Nucleus striae terminalis), which stretches rostrally from the amygdaloid body to the parasep-tal precommissural region, and is composed of a lateral and a medial division (TNA Latin: Divisio lateralis, - medialis); (b) the sublenticular extended amygdala (TNA Latin: Pars sublenticularis amygdalae); and (c) the interstitial amygda-loid nucleus, also known as interstitial nucleus of the pos-terior limb of the anterior commissure (TNA Latin: Nucleus interstitialis amygdalae; Latin synonym: Nucleus interstitialis cruris posterioris commissurae anterioris); for further discussion, see Extended amygdala.

(4) The olfactory amygdala (TNA Latin: Amygdala olfac-toria), which projects heavily to the central and medial amyg-daloid nuclei and only to a small part of the basolateral nuclear group. It comprises: (a) the anterior amygdaloid area (TNA Latin: Area amygdaloidea anterior), an extensive, ill-defined transitional area between the amygdaloid body and pallidostriatal structures in the rostral basal forebrain; (b) the anterior cortical nucleus (TNA Latin: Nucleus corticalis anterior amygdalae), which extends from the temporal divi-sion of the piriform cortex to the rostral pole of the basolateral nucleus; (c) the posterior cortical nucleus (TNA Latin: Nucleus corticalis posterior amygdalae) located near the dor-solateral end of the uncus; (d) the ventral cortical nucleus (TNA Latin: Nucleus corticalis ventralis amygdalae), which occupies most of the semilunar gyrus; (e) the nucleus of the lateral olfactory tract (TNA Latin: Nucleus tractus olfactorii lateralis), which is not unequivocally identified in the human brain; (f) the amygdalohippocampal transition area (TNA Latin: Area transitionis amygdalohippocampalis), the most caudal amygdaloid structure; (g) the amygdalopiriform transition area (TNA Latin: Area transitionis amygdalopiri-formis), an extensive bandlike gray matter at the level of the semicircular sulcus; and (h) the periamygdaloid cortex, also known as the parahippocampal amygdaloid transition area (TNA Latin: Cortex periamygdaloideus; Latin synonym:

Fig. A14 Weigert-stained coronal section of the cerebrum from the Jelgersma Collection showing the amygdaloid complex, bordered later-ally by the temporal part of the anterior commissure and dorsally by the basal forebrain (from ten Donkelaar 2011)

Chapter A

14

Area transitionis amygdaloparahippocampalis), which lies at the semianular sulcus, interposed between the ventral cortical nucleus and the ambient gyrus. It was also called the sulcal part of the periamygdaloid cortex.

Development: The development of the amygdaloid body remains largely unsolved, although cell-birthday pat-terns are available for some species, indicating a rostrocau-

dal gradient. Gene expression data suggest that the basolateral nuclear group is essentially a specialized caudal part of the ventral pallium (Puelles L, et al. 2016 J Chem Neuroanat 75:2–19), whereas the amygdalohippocampal transition area and the associated posterior cortical nucleus seem to be related to the medial pallium. The central amyg-daloid nucleus derives from pallidal and diagonal subpal-

Cd CI

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Fig. A15 Organization of the human basal forebrain with the current subdivision of the basal nuclei and the amygdaloid complex from rostral (a) to caudal (d). Comparable structures are indicated in various colors. Transition areas are indicated as parts of the striatum, but do show some amygdaloid features. The large dots indicate the large, cholinergic cells of the basal nuleus of Meynert (BM). ac anterior commissure, BL basolateral amygdala, BST bed nucleus of the stria terminalis, Cd caudate nucleus, Ce central amygdaloid nucleus, cho chiasma opticum, Cl claustrum, Db diagonal band of Broca, f fornix, GP globus pallidus, GPe, GPi external and internal parts of globus pallidus, Hip hippocampus, In insula, M medial amygdaloid nucleus, ot optic tract, Put putamen, S septum, Th thalamus, VP ventral pallidum, VS ventral striatum (after Heimer L, et al. 1991 Prog Brain Res 87:109–165; from ten Donkelaar et al. 2006)

Fig. A16 (a–f) Series of Nissl-stained frontal sections of the human amygdaloid complex (after ten Donkelaar 2011). AA anterior amygda-loid area, ac anterior commissure, acta amygdaloclaustral transition area, apta amygdalopiriform transition area, asta amygdalostriatal tran-sition area, Bl basolateral amygdaloid nucleus, Bm basomedial amyg-daloid nucleus, C central amygdaloid nucleus, CC cauda of caudate

nucleus, Coa, Cop anterior and posterior cortical amygdaloid nuclei, dCl dorsal claustrum, EN entorhinal cortex, GP globus pallidus, Hip hippocampus, L lateral amygdaloid nucleus, M medial amygdaloid nucleus, NBM basal nucleus of Meynert, ot optic tract, pp putaminal peduncle, Put putamen, ss semilunar sulcus, st stria terminalis, UN uncus, vCl ventral claustrum

Chapter A

15

a b

c d

e f

Chapter A

16

a

c

b

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Fig. A17 Development of the human amygdaloid complex (from ten Donkelaar et al. 2006): (a) frontal section of a 35-mm-CRL embryo; (b, c) the amygdaloid complex in a 4-month-old fetus and an 8-month-old fetus, respectively. The centromedial cell group (CM) and its derivatives are shown in red and the corticobasolateral cell group (CoBL) and its derivatives in light red. ac anterior commissure, Bl large-celled part of basal nucleus, Bs small-celled part of basal nucleus, C central nucleus, Cl claustrum, Co cortical nucleus, EN entorhinal cortex (with cell nests), GP globus pallidus, Hip hippocampus, L lateral nucleus, M medial nucleus, Str striatum

lial domains (Puelles L, et  al. 2016 Brain Struct Funct 221:3027–3065). The origin of the medial amygdaloid nucleus is unclear.

Developmental studies of the human amygdaloid body are few (Macchi G 1951  J Comp Neurol 95:245–305; Humphrey T 1968 J Comp Neurol 132:135–166; Kahle W 1969 Die Entwicklung der menschlichen Groβhirnhemisphäre. Springer, Berlin-Heidelberg-New York; Ulfig N, et al. 2003 Ann NY Acad Sci 985:22–33; Müller F, O’Rahilly R 2006 J Anat (Lond) 208:547–564). Its primordium is recognized as a thickening in the ventrocaudal wall of the intraventricular foramen as soon as the cerebral hemisphere has evaginated (Carnegie stages 14–16). Apparently, slightly later, the medial amygdaloid nucleus develops first, followed by the basolateral complex later at CS20. Most of the amygdaloid nuclei arise from the medial ventricular eminence, and all amygdaloid nuclei can be identified by CS21–22. In the fifth and sixth gestational month, the inferior part of the amygda-loid body reveals cell-dense columns merging with the cau-dal part of the ventricular eminence (Fig. A17). These columns contain vimentin-positive glial fibers, which pro-

vide a scaffold for migrating neurons. In the seventh and eighth gestational months, distinct reorganization of the cytoarchitecture of the amygdaloid body occurs, accompa-nied by a rearrangement and disappearance of vimentin- positive fibers, leading to a high degree of maturity in the eighth gestational month.

Fiber connections (Fig. A18): The amygdaloid body has extensive fiber connections. The centromedial nuclear group is the main output channel of the amygdaloid body. The lateral olfactory tract (TNA Latin: Tractus olfacto-rius lateralis) carries secondary olfactory fibers to the cor-tical and medial amygdaloid nuclei. The stria terminalis or dorsal amygdalofugal bundle; TNA Latin: Stria termi-nalis; eponym: fascia or bundle of Foville) emerges from the caudomedial aspect of the amygdaloid body from where it runs a long course to the anterior commissure. Immediately dorsocaudal to that commissure, it splits up into precommissural, commissural and postcommissural components. The stria terminalis contains both amygda-lofugal and amygdalopetal fibers. The ventral amygda-lofugal bundle (TNA Latin: Fasciculus amygdalofugalis

Chapter A

17

ventralis) is a large assembly of rather loosely arranged fibers, which extend from the amygdaloid complex to the diencephalon. It contains also amygdalopetal fibers from the brain stem. The central amygdaloid nucleus gives rise to a large projection to the brain stem via the ventral amygdalofugal bundle. The caudalmost fibers are the amygdalotegmental fibers (TNA Latin: Fibrae amygda-lotegmentales; Hopkins DA 1975 Neurosci Lett 1:263–270).

Amygdaloclaustral transition area, see Amygdaloid bodyAmygdaloid complex, see Amygdaloid bodyAmygdalohippocampal transition area, see Amygdaloid

bodyAmygdalopiriform transition area, see Amygdaloid bodyAmygdalotegmental fibers, see Amygdaloid bodyAndersch, Carl Samuel (1732–1777): German anato-

mist who described the inferior ganglion of the glossopha-ryngeal nerve, published in 1797 by his nephew (Tractatio anatomico­physiologica de nervis humani corporis aliqui­

bus, quam edidit Ernst Ph. Andersch. Fasch, Königsberg, 1797); see Ganglion of Andersch.

Andreas Retzius, Gyri of: The gyri of Andreas Retzius or subsplenial gyri (TNA Latin: Dentes subiculi; Latin syn­onym: Gyri subspleniales) form the caudal part of CA1 at the hippocampal tail, described by Gustav Retzius (1896; see Retzius) and dedicated to his father Anders (Andreas) Adolf Retzius (1796–1860). The term subsplenial gyri indi-cates their position below the splenium of the corpus callosum.

Angular gyrus: The angular gyrus (TNA Latin: Gyrus angularis) is a part of the inferior parietal lobule formed by the cortex surrounding the end of the superior temporal sul-cus; see Cerebral cortex, Gyri for illustration.

Anococcygeal nerve, see Coccygeal plexusAnsa cervicalis: The ansa cervicalis (TNA Latin: Ansa cer-

vicalis) is a loop of nerve fibers from the cervical plexus, formed by the superior root (TNA Latin: Radix superior) from C1 and C2, which adheres to the hypoglossal nerve, and the inferior root (TNA Latin: Radix inferior) from C2 and C3. It lies super-ficial to the internal jugular vein within the carotid sheath in the carotid triangle. Its infrahyoid branches (TNA Latin: Rami infrahyoidei) innervate the sternothyroid, sternohyoid and omo-hyoid muscles; see Cervical plexus for illustration.

Ansa lenticularis: The ansa lenticularis (TNA Latin: Ansa lenticularis) is a part of the efferent projections of the globus pallidus to the thalamus. It forms a compact, conspic-uous bundle of myelinated fibers running around the internal capsule to the thalamus, instead of traversing it as the len-ticular fasciculus does; see Basal nuclei, Fiber connections for illustration.

Ansa peduncularis: The ansa peduncularis or pedun-cular loop (TNA Latin: Ansa peduncularis) contains cortico-thalamic and thalamotemporal as well as amygdalothalamic and amygdalohypothalamic components, the latter two form the ventral amygdalofugal bundle.

Ansa pectoralis: The ansa pectoralis (TNA Latin: Ansa pectoralis) is a loop that may connect the medial and lateral pectoral nerves.

Ansa subclavia: The ansa subclavia (TNA Latin: Ansa subclavia; eponym: ansa of Vieussens) is a loop of nerve fibers around the subclavian artery connecting the middle cervical ganglion and the cervicothoracic ganglion; see Cervical ganglia for illustration.

Ansa of Vieussens: Eponym for the ansa subclavia.Ansoparamedian fissure: Synonym for the lunogracile

fissure; see Cerebellum, Subdivision.Anterior ampullary nerve, see Vestibular nerveAnterior amygdaloid area, see Amygdaloid bodyAnterior antebrachial interosseous nerve, see Median

nerve

ST

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Fig. A18 Overview of the amygdala and extended amygdala. The cen-tromedial nuclei (CM) and the extended amygdala are indicated in red, and the basolateral amygdala (BL) and cortical amygdala (Co) in light red. A anterior thalamic nucleus, ac anterior commissure, BST bed nucleus of stria terminalis, cc corpus callosum, Cl claustrum, f fornix, PHG parahippocampal gyrus, GPi internal globus pallidus, HY hypo-thalamus, Put putamen, ST stria terminalis, 20–22 temporal cortical areas (from ten Donkelaar et al. 2006)

Chapter A