Desk Reference for Neuroanatomy: A Guide to Essential Terms

165 Pages·1977·3.364 MB·English

by  Dr. Isabel Lockard (auth.)

Isabel Lockard
Desk Reference for
Neuroanatomy
A Guide to Essential Terms
I]
Springer-Verlag
New York Heidelberg Berlin
Dr. Isabel Lockard
Medical University of South Carolina
Charleston, South Carolina 29401
Library of Congress Cataloging in Publication Data
Lockard, Isabel, 1915-
Desk reference for neuroanatomy.
Bibliography: p.
1. Neuroanatomy-Dictionaries. 2. Neurology
Dictionaries. 3. Neurophysiology-Dictionaries. I. Title.
QM451.L62 611'.8 77-21707
All rights reserved.
No part of this book may be translated or reproduced in any form without written
permission from Springer-Verlag.
© 1977 by Springer-Verlag, New York Inc.
Softcover reprint of the hardcover 1s t edition 1977
987 6 5 4 3 2 I
ISBN-13: 978-1-4684-0052-6 e-ISBN-13: 978-1-4684-0050-2
001: 10.1007/978-1-4684-0050-2
Dedicated with affection and gratitude to
Dr. Elizabeth C. Crosby
to whose teaching, written and oral, lowe so much
"When I use a word," Humpty Dumpty said, in rather
a scornful tone, "it means just what I choose it to mean
neither more nor less."
"The question is," said Alice, "whether you can make
words mean so many different things."
"The question is," said Humpty Dumpty, "which is to
be master-that's all.''
-from . 'Through the Looking Glass"
by Lewis Carroll
Preface
The main purpose of this book is to provide ready access to key information on
parts of the nervous system. The student of neuroanatomy frequently encounters terms
from such closely related anatomical fields as the gross anatomy of the peripheral
nervous system, the histology and embryology of the nervous system and the anatomy
of the eye and ear. Consequently many of the terms from these areas have been
included. Although no complete listing of terms from cognate fields has been
attempted, some of the more frequently encountered terms from neurophysiology,
neuropathology and clinical neurology are also included.
References given for some entries are not intended to be exhaustive but to direct
the reader's attention in some instances to places where the term has been introduced
and in others to places where a more complete discussion of the subject is available.
Another purpose is to equate the terms that are synonyms and to differentiate
between those that are not. In addition, an attempt has been made to include older
terms and eponyms together with their newer counterparts.
Because not all authors agree on the precise meanings of many terms, some of the
definitions given here may seem, and indeed often are, arbitrary. Although this author
claims no special authority in the selection of preferred terms, some selection was
necessary. If we are to use words that convey exactly the ideas that we intend, it is
necessary to draw some semblance of order out of the overlapping and imprecise
terminology of our field. When it comes to deciding on the meaning of a word, we are
left with Humpty Dumpty's admonition to Alice-"The question is, which is to be
master-that's all."
Isabel Lockard
Note
The entries in this book are organized primarily by the type of anatomical feature,
and alphabetized principal word by principal word, without regard to punctuation or
connectives. For example, the user who is looking for the cochlear nerve should look
under "nerve, cochlear;" and the user who is looking for the tract of Barnes should
look between "tract, Arnold's" and "tract, Burdach's."
Biographical entries are listed by last name, and frequently refer the user to
anatomical features associated with each historical figure.
The author is aware that the user will often see a phrase from a different
perspective, and has tried to supply enough cross references to facilitate use without
extensive repetition of definitions.
a
A-fiber heavily medullated, fast conducting nerve fiber, as large as 22 JLm in
diameter.
aberrant pyramidal see fibers, aberrant pyramidal.
acalculia inability to complete simple arithmetical problems, associated with inju-
ries in the region of the supramarginal gyrus of the dominant cerebral
hemisphere.
accommodation adaptation of the eye for near vision.
acervulus calcareous body in the pineal body. Syn: brain sand.
acetylcholine neurotransmitter released at nerve endings during transmission of a
nerve impulse, at motor end-plates in skeletal muscle, at postganglionic para
sympathetic endings, at postganglionic sympathetic endings on sweat glands,
and at synapses in parts of the central nervous system and in autonomic ganglia.
ACh see acetylcholine.
Achillini, Alessandro [1463-1512] anatomist of Bologna who made original obser-
vations on the hippocampus.
acoustic pertaining to the ear. For acoustic nerve, tubercle, see the nouns.
Adamkiewicz, Albert [1850-1921] Austrian pathologist noted for his description of
the crescent-shaped cells under the neurolemma of medullated nerve fibers, and
for the first extensive study on the blood vessels of the spinal cord [1881, 1882].
ADH abbreviation for antidiuretic hormone. See vasopressin.
adhesio interthalamica [N .A.] see massa intermedia.
adiadochokinesis cerebellar disorder characterized by the inability to perform rap-
idly alternate contractions of antagonistic muscles, as in finger tapping or alter
nate pronation and supination of the hands.
Adler, Alfred [1870-1937] Viennese psychiatrist who with Jung and Freud laid the
foundations of modem psychology.
adrenergic releasing an epinephrine-like substance; pertaining to certain postgan-
glionic-sympathetic nerve endings.
2 alTenspalte
alTenspaite see fissure, lunate.
alTerent conducting toward.
alTerent neuron see neuron, afferent.
afterbrain see hindbrain.
after-nystagmus nystagmus in which the eye movements continue after the stimu-
lus is removed.
agent, adrenergic blocking compound which selectively inhibits the responses of
effector cells to adrenergic sympathetic nerve impulses and to epinephrine and
related amines.
agnosia loss of ability to recognize familiar objects.
agnosia, auditory verbal inability to recognize spoken words.
agnosia, tactile inability to recognize objects by touch. Syn: astereognosis.
agnosia, visual object inability to recognize objects by sight.
agnosia, visual verbal inability to recognize written words. See also alexia.
agraphia inability to copy.
AICA See artery, anterior inferior cerebellar.
akinesia absence of the initiation, implementation, and facility of execution of
movement.
ala alba lateralis [L. ala-wing] see area, acoustic.
ala centralis most rostral subdivision of the cerebellar hemisphere, lateral to and
continuous with the central lobule of the vermis. See cerebellum, lobules
[hemispheres].
ala cinerea [L. cinereus-ashy] see trigone, vagal.
alar plate see plate, alar.
alba pertaining to the white matter of the brain.
alexia loss of ability to interpret written symbols; word blindness, therefore,
inability to read. See also visual verbal agnosia.
allocortex unlaminated or partly laminated cortex of the archipallium and paleopal-
lium. See also cortex, heterogenetic.
alveus [L. trough or canal] layer of myelinated fibers on the ventricular smface of
the hippocampus arising from cells in the cornu ammonis and collecting to form
the fimbria.
Alzheimer, Alois [1864-1915] German physician and neuropathologist who in 1907
described the pathologic changes in cortical neurons, characteristic of presenile
sclerosis.
amaurosis [Gr. darkening] blindness.
amiculum olivae [L. amiculum-little overcoat] see capsule, olivary.
amino butyric acid see gamma-aminobutyric acid.
Ammon Egyptian god, represented with ram's horns, hence the term cornu
ammonis, q. v.
Ammon's formation see formation, hippocampal; hippocampus.
Ammon's horn see cornu ammonis.
Ammon's pyramids pyramidal cells of the cornu ammonis.
amphicyte satellite cell in the ectodermal capsule of ganglion cells.
ampulla, membranous [L. ampulla-jug] dilatation at one end of each semicircu-
lar duct [anterior inferior end of the superior duct, posterior inferior end of the
posterior duct, and anterior end of the horizontal duct] and containing the crista
ampullaris, the sensory end organ of the duct.
ansa cruralis 3
ampulla, osseous part of the bony labyrinth of the internal ear, which houses a
membranous ampulla.
amyelia absence of the spinal cord.
amygdala [Gr. amygdale-almond] subdivision of the basal ganglia located in the
temporal lobe, anterior to the inferior hom of the lateral ventricle and partly
beneath the uncus. Its two main portions are a corticomedial nuclear group
[anterior amygdaloid area, nucleus of the lateral olfactory tract, and the medial
cortical and central amygdaloid nuclei] with olfactory and subcortical connec
tions, and a basolateral nuclear group [basal, lateral, and accessory basal amyg
daloid nuclei] connected primarily with the overlying cortex. [Crosby, Hum
phrey, and Lauer, 1962]. Syn: archistriatum.
analgesia insensitivity to pain without loss of consciousness.
Andersch, Carl Samuel [1732-1777] German anatomist [G6ttingen] who described
the inferior [petrosal] ganglion of the glossopharyngeal nerve [ganglion of
Andersch].
anesthesia absence of sensation.
aneurism, Berry saccular dilatation of a cerebral artery, usually located on or near
the circle of Willis.
angiography procedure in which a contrast medium is injected into a vessel, such
as an artery, to render the vessel and its branches visible by radiography.
angle, cerebellopontine area on the ventrolateral surface of the brain stem where
the cerebellum, pons, and medulla meet and where the facial and acoustic nerves
attach to the brain.
angle, filtration see angle, iris.
angle, iridial see angle, iris.
angle, iris recess at the junction of the iris and cornea where aqueous humor leaves
the anterior chamber of the eye. Syn: filtration angle: iridial angle.
angle, Rolandic acute angle formed by the central sulcus and the superior border of
the frontal lobe.
angie, venous point at the interventricular foramen where the terminal vein turns
sharply posteriorly to enter the internal cerebral vein.
anhidrosis absence of sweating.
animal, decerebrate one in which the brain has been severed at the level of the
midbrain.
animal, spinal one in which the spinal cord has been separated from the brain.
animal, thalamic one in which the cerebrum has been separated from the
diencephalon.
aniscoria inequality in pupillary diameter of the two eyes.
ankle jerk see reflex, Achilles.
annulus see anulus.
anomia loss of ability to recall or to recognize the names of objects or people.
anosmia loss or lack of the sense of smell.
anosognosia inability of a person to recognize a disease or bodily defect in himself.
ansa cervicalis [L. ansa-handle] [N.A.] loop of the cervical plexus, formed by
the union of the descendens hypoglossi, containing fibers from the CI spinal
nerve, and the descendens cervicalis, containing fibers from C2 and C3. Its
branches supply the infrahyoid muscles. Syn: ansa hypoglossi.
ansa cruralis see ansa peduncularis.
4 ansa hypoglossi
ansa hypoglossi see ansa cervicaIis.
ansa lenticularis [N.A.] 1. bundle of nerve fibers arising primarily from cells in the
globus pallidus and putamen, emerging from the ventral surface of the lentiform
nucleus, passing medially and dorsally into the diencephalon, then, after most
fibers synapse in the nucleus of the field of Forel, ending in the midbrain
tegmental gray including the caudal red nucleus. 2. several bundles of nerve
fibers emerging from the lentiform nucleus and subdivided into three groups: a
ventral division or ansa lenticularis proper [see 1 above], a dorsal division [the
lenticular fasciculus], and an intermediate division [the subthalamic fasciculus].
ansa peduncularis [N .A.] fibers of the inferior thalamic peduncle and ansa lenticu-
laris combined into one bundle which bends around the posterior limb of the
internal capsule as it enters the midbrain. Syn: ansa cruralis, Reil's ansa.
ansa sacralis loop of fibers interconnecting the caudal ends of the two sympathetic
trunks.
ansa subclavia [N .A.] loop of nerve fibers around the subclavian artery connecting
the inferior and middle cervical sympathetic ganglia or sometimes the inferior
ganglion and the recurrent nerve.
ansa of Vieussens see ansa subclavia.
ansiform describing an arc.
anterior column see horn, ventral; funiculus, ventral.
anterior commissure see commissure, anterior.
anticholinesterase substance which blocks the action of cholinesterase.
antidiuretic hormone see vasopressin.
antidromic conducting impluses in the direction opposite to the usual direction of
conduction.
antrum, interventricular, of Wilder portion of the third ventricle with which the
two interventricular foramina communicate.
anulus of the aqueduct [L. annulus-ring] periaqueductal gray.
anulus of Vieussens see ansa subclavia.
aperture, lateral, of the fourth ventricle opening between each lateral recess of the
fourth ventricle and the subarachnoid space. Syn: foramen of Luschka; foramen
of Key and Retzius.
aperture, median, of the fourth ventricle midline opening in the posterior medul-
lary velum through which the medullary portion of the fourth ventricle communi
cates with the subarachnoid space. Syn: foramen of Magendie.
aphasia language disorder involving a loss of ability to comprehend or express the
signs and symbols by which man communicates with his peers.
aphasia, semantic loss of the ability to understand the importance and relationship
of things in the external environment.
aphonia loss of voice; inability to phonate.
apparatus, Golgi see apparatus, reticular.
apparatus, reticular organoid found in nerve cell cytoplasm, most highly devel-
oped in large nerve cell bodies, and in some cases extending into the dendrites.
Syn: Golgi apparatus.
apparatus, subneural modified sarcolemma of a motor end-plate.
apraxia inability to carry out a purposive movement, the nature of which the
patient understands, in the absence of severe motor paralysis, sensory loss, and
ataxia.