Gale Encyclopedia of Neurological Disorders pdf

The
GALE
ENCYCLOPEDIA
of
NEurological
Disorders
FrontMatter1.qxd 10/5/04 2:21 PM Page i
VOLUME
A-L
1
The
GALE
ENCYCLOPEDIA
of
NEurological
Disorders
STACEY L. CHAMBERLIN, BRIGHAM NARINS, EDITORS
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The Gale Encyclopedia of Neurological Disorders
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Printed in the United States of America
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LIBRARY OF CONGRESS CATALOGING-IN-PUBLICATION DATA
The Gale encyclopedia of neurological disorders / Stacey L. Chamberlin, Brigham Narins,
editors.
p. ; cm.
Includes bibliographical references and index.
ISBN 0-7876-9150-X (set hardcover : alk. paper) — ISBN
0-7876-9151-8 (v. 1) — ISBN
0-7876-9152-6 (v. 2)
1. Neurology—Encyclopedias.
[DNLM: 1. Nervous System Diseases—Encyclopedias—English. 2. Nervous System
Diseases—Popular Works. WL 13 G151 2005] I. Title: Encyclopedia of neurological
disorders. II. Chamberlin, Stacey L. III. Narins, Brigham, 1962– IV. Gale Group.
RC334.G34 2005
616.8'003—dc22 2004021644
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CONTENTS
List of Entries vii

Introduction xiii
Advisory Board xv
Contributors xvii
Entries
Volume 1: A–L 1
Volume 2: M–Z 511
Glossary 941
General Index 973
GALE ENCYCLOPEDIA OF NEUROLOGICAL DISORDERS
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LIST OF ENTRIES
❙
A
Abulia
Acetazolamide
Acupuncture
Acute disseminated encephalomyelitis
Adrenoleukodystrophy
Affective disorders
Agenesis of the corpus callosum
Agnosia
AIDS
Alcohol-related neurological disease
Alexander disease
Alpers’ disease
Alternating hemiplegia
Alzheimer disease
Amantadine
Amnestic disorders

Amyotrophic lateral sclerosis
Anatomical nomenclature
Anencephaly
Aneurysms
Angelman syndrome
Angiography
Anosmia
Anticholinergics
Anticonvulsants
Antiepileptic drugs
Antimigraine medications
Antiparkinson drugs
Antiviral drugs
Anxiolytics
Aphasia
Apraxia
Arachnoid cysts
Arachnoiditis
Arnold-Chiari malformation
Arteriovenous malformations
Aspartame
Asperger’s disorder
Assistive mobile devices
Ataxia-telangiectasia
Ataxia
Atomoxetine
Attention deficit hyperactivity
disorder
Autism
Autonomic dysfunction

❙
B
Back pain
Bassen-Kornzweig syndrome
Batten disease
Behçet disease
Bell’s palsy
Benign positional vertigo
Benzodiazepines
Beriberi
Binswanger disease
Biopsy
Blepharospasm
Bodywork therapies
Botulinum toxin
Botulism
Brachial plexus injuries
Brain anatomy
Brain and spinal tumors
Brown-Séquard syndrome
❙
C
Canavan disease
Carbamazepine
Carotid endarterectomy
Carotid stenosis
Carpal tunnel syndrome
Catechol-O-methyltransferase
inhibitors
Central cord syndrome

Central nervous system
Central nervous system stimulants
Central pain syndrome
Cerebellum
Cerebral angiitis
Cerebral cavernous malformation
Cerebral circulation
Cerebral dominance
Cerebral hematoma
Cerebral palsy
Channelopathies
Charcot-Marie-Tooth disorder
Cholinergic stimulants
Cholinesterase inhibitors
Chorea
Chronic inflammatory demyelinating
polyneuropathy
Clinical trials
Congenital myasthenia
Congenital myopathies
Corpus callosotomy
Corticobasal degeneration
Craniosynostosis
Craniotomy
Creutzfeldt-Jakob disease
CT scan
Cushing syndrome
Cytomegalic inclusion body disease
❙
D

Dandy-Walker syndrome
Deep brain stimulation
Delirium
Dementia
Depression
Dermatomyositis
Devic syndrome
Diabetic neuropathy disease
Diadochokinetic rate
Diazepam
Dichloralphenazone
Dichloralphenazone, Isometheptene,
and Acetaminophen
Diencephalon
Diet and nutrition
Disc herniation
Dizziness
Dopamine receptor agonists
Dysarthria
Dysesthesias
Dysgeusia
Dyskinesia
Dyslexia
Dyspraxia
Dystonia
❙
E
Electric personal assistive mobility
devices
GALE ENCYCLOPEDIA OF NEUROLOGICAL DISORDERS

vii
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Electroencephalography
Electromyography
Empty sella syndrome
Encephalitis and Meningitis
Encephalitis lethargica
Encephaloceles
Encephalopathy
Endovascular embolization
Epidural hematoma
Epilepsy
Exercise
❙
F
Fabry disease
Facial synkinesis
Fainting
Fatigue
Febrile seizures
Felbamate
Fisher syndrome
Foot drop
Fourth nerve palsy
Friedreich ataxia
❙
G
Gabapentin
Gaucher disease
Gene therapy

Gerstmann-Straussler-Scheinker disease
Gerstmann syndrome
Glossopharyngeal neuralgia
Glucocorticoids
Guillain-Barré syndrome
❙
H
Hallucination
Headache
Hearing disorders
Hemianopsia
Hemifacial spasm
Hereditary spastic paraplegia
Holoprosencephaly
HTLV-1 Associated Myelopathy
Huntington disease
Hydantoins
Hydranencephaly
Hydrocephalus
Hydromyelia
Hypersomnia
Hypotonia
Hypoxia
❙
I
Idiopathic neuropathy
Inclusion body myositis
Incontinentia pigmenti
Infantile spasms
Inflammatory myopathy

Interferons
❙
J
Joubert syndrome
❙
K
Kennedy’s disease
Klippel Feil syndrome
Krabbe disease
Kuru
❙
L
Lambert-Eaton myasthenic syndrome
Laminectomy
Lamotrigine
Learning disorders
Lee Silverman voice treatment
Leigh disease
Lennox-Gastaut syndrome
Lesch-Nyhan syndrome
Leukodystrophy
Levetiracetam
Lewy body dementia
Lidocaine patch
Lissencephaly
Locked-in syndrome
Lupus
Lyme disease
❙
M

Machado-Joseph disease
Magnetic resonance imaging (MRI)
Megalencephaly
Melodic intonation therapy
Ménière’s disease
Meninges
Mental retardation
Meralgia paresthetica
Metachromatic leukodystrophy
Microcephaly
Mitochondrial myopathies
Modafinil
Moebius syndrome
Monomelic amyotrophy
Motor neuron diseases
Movement disorders
Moyamoya disease
Mucopolysaccharidoses
Multi-infarct dementia
Multifocal motor neuropathy
Multiple sclerosis
Multiple system atrophy
Muscular dystrophy
Myasthenia, congenital
Myasthenia gravis
Myoclonus
Myofibrillar myopathy
Myopathy
Myotonic dystrophy
❙

N
Narcolepsy
Nerve compression
Nerve conduction study
Neurofibromatosis
Neuroleptic malignant syndrome
Neurologist
Neuromuscular blockers
Neuronal migration disorders
Neuropathologist
Neuropsychological testing
Neuropsychologist
Neurosarcoidosis
Neurotransmitters
Niemann-Pick Disease
❙
O
Occipital neuralgia
Olivopontocerebellar atrophy
Opsoclonus myoclonus
Organic voice tremor
Orthostatic hypotension
Oxazolindinediones
❙
P
Pain
Pallidotomy
Pantothenate kinase-associated
neurodegeneration
Paramyotonia congenita

Paraneoplastic syndromes
Parkinson’s disease
Paroxysmal hemicrania
Parsonage-Turner syndrome
Perineural cysts
Periodic paralysis
Peripheral nervous system
Peripheral neuropathy
Periventricular leukomalacia
Phantom limb
Pharmacotherapy
Phenobarbital
Pick disease
Pinched nerve
Piriformis syndrome
Plexopathies
Poliomyelitis
viii
GALE ENCYCLOPEDIA OF NEUROLOGICAL DISORDERS
List of Entries
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Polymyositis
Pompe disease
Porencephaly
Positron emission tomography (PET)
Post-polio Syndrome
Primary lateral sclerosis
Primidone
Prion diseases
Progressive multifocal

leukoencephalopathy
Progressive supranuclear palsy
Pseudobulbar palsy
Pseudotumor cerebri
❙
R
Radiation
Radiculopathy
Ramsay-Hunt syndrome type II
Rasmussen’s encephalitis
Reflex sympathetic dystrophy
Refsum disease
Repetitive motion disorders
Respite
Restless legs syndrome
Rett syndrome
Reye syndrome
❙
S
Sandhoff disease
Schilder’s disease
Schizencephaly
Schizophrenia
Sciatic neuropathy
Sciatica
Seizures
Septo-optic dysplasia
Shaken baby syndrome
Shingles
Single Proton Emission Computed

Tomography
Sixth nerve palsy
Sjogren-Larsson Syndrome
Sleep apnea
Social workers
Sodium oxybate
Sotos syndrome
Spasticity
Speech synthesizer
Spina bifida
Spinal cord infarction
Spinal cord injury
Spinal muscular atrophy
Spinocerebellar ataxia
Status epilepticus
Stiff person syndrome
Striatonigral degeneration
Stroke
Sturge-Weber syndrome
Stuttering
Subacute sclerosing panencephalitis
Subdural hematoma
Succinamides
Swallowing disorders
Sydenham’s chorea
Syringomyelia
❙
T
Tabes dorsalis
Tay-Sachs disease

Temporal arteritis
Temporal lobe epilepsy
Tethered spinal cord syndrome
Third nerve palsy
Thoracic outlet syndrome
Thyrotoxic myopathy
Tiagabine
Todd’s paralysis
Topiramate
Tourette syndrome
Transient global amnesia
Transient ischemic attack
Transverse myelitis
Traumatic brain injury
Tremors
Trigeminal neuralgia
Tropical spastic paraparesis
Tuberous sclerosis
❙
U
Ulnar neuropathy
Ultrasonography
❙
V
Valproic acid and divalproex
sodium
Vasculitic neuropathy
Vasculitis
Ventilatory assistance devices
Ventricular shunt

Ventricular system
Vertebrobasilar disease
Vestibular schwannoma
Visual disturbances
Vitamin/nutritional deficiency
Von Hippel-Lindau disease
❙
W
Wallenberg syndrome
West Nile virus infection
Whiplash
Whipple’s Disease
Williams syndrome
Wilson disease
❙
Z
Zellweger syndrome
Zonisamide
GALE ENCYCLOPEDIA OF NEUROLOGICAL DISORDERS
ix
List of Entries
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PLEASE READ—IMPORTANT INFORMATION
The Gale Encyclopedia of Neurological Disorders is
a medical reference product designed to inform and edu-
cate readers about a wide variety of diseases, syndromes,
drugs, treatments, therapies, and diagnostic equipment.
Thomson Gale believes the product to be comprehensive,
but not necessarily definitive. It is intended to supplement,
not replace, consultation with a physician or other health-

care practitioner. While Thomson Gale has made sub-
stantial efforts to provide information that is accurate,
comprehensive, and up-to-date, Thomson Gale makes no
representations or warranties of any kind, including with-
out limitation, warranties of merchantability or fitness for
a particular purpose, nor does it guarantee the accuracy,
comprehensiveness, or timeliness of the information con-
tained in this product. Readers are advised to seek profes-
sional diagnosis and treatment for any medical condition,
and to discuss information obtained from this book with
their healthcare providers.
GALE ENCYCLOPEDIA OF NEUROLOGICAL DISORDERS
xi
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INTRODUCTION
The Gale Encyclopedia of Neurological Disorders
(GEND) is a one-stop source for medical information that
covers diseases, syndromes, drugs, treatments, therapies,
and diagnostic equipment. It keeps medical jargon to a
minimum, making it easier for the layperson to use. The
Gale Encyclopedia of Neurological Disorders presents au-
thoritative and balanced information and is more compre-
hensive than single-volume family medical guides.
SCOPE
Almost 400 full-length articles are included in The
Gale Encyclopedia of Neurological Disorders. Articles
follow a standardized format that provides information at
a glance. Rubrics include:
Diseases
• Definition

• Description
• Demographics
• Causes and symptoms
• Diagnosis
•Treatment team
•Treatment
• Recovery and rehabilitation
• Clinical trials
•Prognosis
• Special concerns
• Resources
•Key terms
Drugs
• Definition
• Purpose
• Description
• Recommended dosage
•Precautions
• Side effects
• Interactions
• Resources
•Key terms
Treatments
• Definition
• Purpose
•Precautions
• Description
•Preparation
• Aftercare
• Risks

• Normal results
• Resources
•Key terms
INCLUSION CRITERIA
A preliminary topic list was compiled from a wide va-
riety of sources, including professional medical guides,
consumer guides, and textbooks and encyclopedias. The
advisory board, made up of seven medical and healthcare
experts, evaluated the topics and made suggestions for in-
clusion. Final selection of topics to include was made by
the medical advisors in conjunction with Gale editors.
ABOUT THE CONTRIBUTORS
The essays were compiled by experienced medical
writers, physicians, nurses, and pharmacists. GEND med-
ical advisors reviewed most of the completed essays to in-
sure that they are appropriate, up-to-date, and medically
accurate.
GALE ENCYCLOPEDIA OF NEUROLOGICAL DISORDERS
xiii
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HOW TO USE THIS BOOK
The Gale Encyclopedia of Neurological Disorders
has been designed with ready reference in mind:
•Straight alphabetical arrangement allows users to lo-
cate information quickly.
• Bold faced terms function as print hyperlinks that point
the reader to full-length entries in the encyclopedia.
•A list of key terms is provided where appropriate to de-
fine unfamiliar words or concepts used within the con-
text of the essay.

• Cross-references placed throughout the encyclopedia di-
rect readers to where information on subjects without their
own entries can be found. Cross-references are also used to
assist readers looking for information on diseases that are
now known by other names; for example, there is a cross-
reference for the rare childhood disease commonly known
as Hallervorden-Spatz disease that points to the entry en-
titled Pantothenate kinase-associated neurodegeneration.
•A Resources section directs users to sources of further
information, which include books, periodicals, websites,
and organizations.
•A glossary is included to help readers understand unfa-
miliar terms.
•A comprehensive general index allows users to easily
target detailed aspects of any topic.
GRAPHICS
The Gale Encyclopedia of Neurological Disorders is
enhanced with over 100 images, including photos, tables,
and customized line drawings.
xiv
GALE ENCYCLOPEDIA OF NEUROLOGICAL DISORDERS
Introduction
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ADVISORY BOARD
Laurie Barclay, MD
Neurologist and Writer
Tampa, FL
F. James Grogan, PharmD
Pharmacist, Clinician, Writer,
Editor, and Consultant

Swansea, IL
Joel C. Kahane, PhD
Professor, Director of the
Anatomical Sciences Laboratory
The School of Audiology and
Speech-Language Pathology
The University of Memphis
Memphis, TN
Brenda Wilmoth Lerner, RN
Nurse, Writer, and Editor
London, UK
Yuen T. So, MD, PhD
Associate Professor
Clinical Neurosciences
Stanford University School of
Medicine
Stanford, CA
Roy Sucholeiki, MD
Professor, Director of the
Comprehensive Epilepsy
Program
Department of Neurology
Loyola University Health System
Chicago, IL
Gil I. Wolfe, MD
Associate Professor
Department of Neurology
The University of Texas
Southwestern Medical Center
Dallas, TX

GALE ENCYCLOPEDIA OF NEUROLOGICAL DISORDERS
xv
An advisory board made up of prominent individuals from the medical and healthcare communities provided invaluable assis-
tance in the formulation of this encyclopedia. They defined the scope of coverage and reviewed individual entries for accu-
racy and accessibility; in some cases they contributed entries themselves. We would therefore like to express our great
appreciation to them:
FrontMatter1.qxd 10/5/04 2:21 PM Page xv
CONTRIBUTORS
Lisa Maria Andres, MS, CGC
Certified Genetic Counselor and
Medical Writer
San Jose, CA
Paul Arthur
Science writer
London, England
Bruno Verbeno Azevedo
Espirito Santo University
Vitória, Brazil
Deepti Babu, MS, CGC
Genetic Counselor
Marshfield Clinic
Marshfield, WI
Laurie Barclay, MD
Neurologist and writer
Tampa, FL
Julia Barrett
Science Writer
Madison, WI
Danielle Barry, MS
Graduate Assisstant

Center of Alcohol Studies
Rutgers University
Piscataway, NJ
Maria Basile, PhD
Medical Writer
Roselle, NJ
Tanja Bekhuis, PhD
Science Writer and
Psychologist
TCB Research
Boalsburg, PA
Juli M. Berwald, PhD
Geologist (Ocean Sciences)
Chicago, Illinois
Robert G. Best, PhD
Director
Division of Genetics
University of South Carolina School
of Medicine
Columbia, SC
Michelle Lee Brandt
Medical Writer
San Francisco, CA
Dawn J. Cardeiro, MS, CGC
Genetic Counselor
Fairfield, PA
Francisco de Paula Careta
Espirito Santo University
Vitória, Brazil
Rosalyn Carson-DeWitt,

MD
Physician and Medical Writer
Durham, NC
Stacey L. Chamberlin
Science Writer and Editor
Fairfax, VA
Bryan Richard Cobb, PhD
Institute for Molecular and Human
Genetics
Georgetown University
Washington, D.C.
Adam J. Cohen, MD
Craniofacial Surgery, Eyelid
and Facial Plastic Surgery,
Neuro-Ophthalmology
Downers Grove, IL
Tish Davidson, AM
Medical Writer
Fremont, CA
James Paul Dworkin, PhD
Professor
Department of Otolaryngology,
Voice/Speech Pathology
Program and Laboratory
Wayne State University
Detroit, MI
L. Fleming Fallon, Jr., MD,
DrPH
Professor
Department of Public Health

Bowling Green State University
Bowling Green, OH
Antonio Farina, MD, PhD
Department of Embryology,
Obstetrics, and Gynecology
University of Bologna
Bologna, Italy
Kevin Fitzgerald
Science Writer and Journalist
South Windsor, CT
Paula Anne Ford-Martin
Medical Writer
Warwick, RI
Lisa A. Fratt
Medical Writer
Ashland, WI
Rebecca J. Frey, PhD
Freelance Medical Writer
New Haven, CT
Sandra L. Friedrich, MA
Science Writer
Clinical Psychology
Chicago, IL
Sandra Galeotti, MS
Science Writer
Sao Paulo, Brazil
GALE ENCYCLOPEDIA OF NEUROLOGICAL DISORDERS
xvii
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Larry Gilman, PhD

Electrical Engineer and Science
Writer
Sharon, VT
Laith Farid Gulli, MD
Consulting Psychotherapist
Lathrup Village, MI
Stephen John Hage, AAAS,
RT(R), FAHRA
Medical Writer
Chatsworth, CA
Brook Ellen Hall, PhD
Science Writer
Loomis, CA
Dan Harvey
Medical Writer
Wilmington, DE
Hannah M. Hoag, MSc
Science and Medical Writer
Montreal, Canada
Brian Douglas Hoyle, PhD
Microbiologist
Nova Scotia, Canada
Cindy L. Hunter, CGC
Genetic Counselor
Medical Genetics Department
Indiana University School of
Medicine
Indianapolis, IN
Alexander I. Ioffe, PhD
Senior Scientist

Geological Institute of the Russian
Academy of Sciences
Moscow, Russia
Holly Ann Ishmael, MS, CGC
Genetic Counselor
The Children’s Mercy Hospital
Kansas City, MO
Joel C. Kahane, PhD
Professor, Director of the
Anatomical Sciences
Laboratory
The School of Audiology and
Speech-Language Pathology
The University of Memphis
Memphis, TN
Kelly Karpa, PhD, RPh
Assistant Professor
Department of Pharmacology
Pennsylvania State University
College of Medicine
Hershey, PA
Karen M. Krajewski, MS, CGC
Genetic Counselor, Assistant
Professor of Neurology
Wayne State University
Detroit, MI
Judy Leaver, MA
Behavioral Health Writer and
Consultant
Washington, D.C.

Adrienne Wilmoth Lerner
University of Tennessee College of
Law
Knoxville, TN
Brenda Wilmoth Lerner, RN
Nurse, Writer, and Editor
London, UK
K. Lee Lerner
Fellow (rt)
Science Policy Institute
London, UK
Agnieszka Maria Lichanska,
PhD
Department of Microbiology and
Parasitology
University of Queensland
Brisbane, Australia
Peter T. Lin, MD
Research Assistant
Member: American Academy of
Neurology, American
Association of Electrodiagnostic
Medicine
Department of Biomagnetic
Imaging
University of California, San
Francisco
Foster City, CA
Iuri Drumond Louro, MD,
PhD

Adjunct Professor
Human and Molecular Genetics
Espirito Santo University
Vitória, Brazil
Nicole Mallory, MS, PA-C
Medical Student
Wayne State University
Detroit, MI
Igor Medica, MD, PhD
Assistant Professor
School of Medicine
University of Rijeka
Pula, Croatia
Michael Mooney, MA, CAC
Consultant Psychotherapist
Warren, MI
Alfredo Mori, MD, FACEM,
FFAEM
Emergency Physician
The Alfred Hospital
Victoria, Australia
Oxford’s Program in Evidence-
Based Health Care
University of Oxford
Oxford, England
Marcos do Carmo Oyama
Espirito Santo University
Vitória, Brazil
Greiciane Gaburro Paneto
Espirito Santo University

Vitória, Brazil
Borut Peterlin, MD, PhD
Neurologist; Consultant Clinical
Geneticist; Director
Division of Medical Genetics
University Medical Center
Lubiana, Slovenia
Toni I. Pollin, MS, CGC
Research Analyst
Division of Endocrinology,
Diabetes, and Nutrition
University of Maryland School of
Medicine
Baltimore, MD
J. Ricker Polsdorfer, MD
Medical Writer
Phoenix, AZ
Scott J. Polzin, MS, CGC
Medical Writer
Buffalo Grove, IL
Jack Raber, PharmD
Principal
Clinipharm Services
Seal Beach, CA
xviii
GALE ENCYCLOPEDIA OF NEUROLOGICAL DISORDERS
Contributors
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Robert Ramirez, DO
Medical Student

University of Medicine and
Dentistry of New Jersey
Stratford, NJ
Richard Robinson
Medical Writer
Tucson, AZ
Jennifer Ann Roggenbuck, MS,
CGC
Genetic Counselor
Hennepin County Medical Center
Minneapolis, MN
Nancy Ross-Flanigan
Science Writer
Belleville, MI
Stephanie Dionne Sherk
Freelance Medical Writer
University of Michigan
Ann Arbor, MI
Lee Alan Shratter, MD
Consulting Radiologist
Kentfield, CA
Genevieve T. Slomski, PhD
Medical Writer
New Britain, CT
Amie Stanley, MS
Genetic Counselor
Medical Genetics
The Cleveland Clinic
Cleveland, OH
Constance K. Stein, PhD

Director of Cytogenetics, Assistant
Director of Molecular
Diagnostics
SUNY Upstate Medical University
Syracuse, NY
Roger E. Stevenson, MD
Senior Clinical Geneticist, Senior
Clinical Laboratory Geneticist
Greenwood Genetic Center
Greenwood, SC
Roy Sucholeiki, MD
Professor, Director of the
Comprehensive Epilepsy
Program
Department of Neurology
Loyola University Health System
Chicago, IL
Kevin M. Sweet, MS, CGC
Cancer Genetic Counselor
James Cancer Hospital, Ohio State
University
Columbus, OH
David Tulloch
Science Writer
Wellington, New Zealand
Carol A. Turkington
Medical Writer
Lancaster, PA
Samuel D. Uretsky, PharmD
Medical Writer

Wantagh, NY
Chitra Venkatasubramanian,
MBBS, MD (internal
medicine)
Resident in Neurology
Department of Neurology and
Neurosciences
Stanford University
Stanford, CA.
Bruno Marcos Verbeno
Espirito Santo University
Vitória, Brazil
Beatriz Alves Vianna
Espirito Santo University
Vitória, Brazil
GALE ENCYCLOPEDIA OF NEUROLOGICAL DISORDERS
xix
Contributors
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GALE ENCYCLOPEDIA OF NEUROLOGICAL DISORDERS
1
A
Key Terms
Basal ganglia A group of brain structures that are
responsible for movement.
Dopamine A brain chemical (neurotransmitter)
responsible for carrying messages throughout the
nervous system, particularly messages regarding
movement.
Frontal lobe The area of the brain responsible for

higher thinking.
Abetalipoproteinemia see Bassen-
Kornzweig syndrome
❙
Abulia
Definition
Abulia is a state in which an individual seems to have
lost will or motivation.
Description
Abulia is not a separate condition; rather, it is a symp-
tom associated with various forms of brain injury. It may
occur in association with a variety of conditions, including
stroke, brain tumor, traumatic brain damage, bleeding into
the brain, and exposure to toxic substances.
Causes and symptoms
Some research suggests that abulia occurs due to mal-
function of the brain’s dopamine-dependent circuitry. In-
juries to the frontal lobe (the area of the brain responsible
for higher thinking) and/or the basal ganglia (the area of
the brain responsible for movement) can interfere with an
individual’s ability to initiate speech, movement, and so-
cial interaction. Abulia has been noted in patients who have
suffered brain injuries due to stroke, bleeding into the brain
from a ruptured aneurysm, trauma, brain tumor, neurolog-
ical disease (such as Parkinson’s disease), psychiatric
condition (such as severe depression or schizophrenia),
and exposure to toxic substances (such as cyclosporin-A).
An individual with abulia may not appear to have
much will or motivation to pursue activities or initiate
conversation. Such an individual may appear apathetic,

disinterested, asocial, quiet or mute, physically slowed or
still (hypokinetic), and emotionally remote.
Diagnosis
Abulia is not an individual diagnosis; it is a symptom
that usually occurs as part of a constellation of symptoms
accompanying a specific disorder. Diagnosis of the un-
derlying disorder depends on the kinds of symptoms that
co-exist with abulia. Psychiatric interview, magnetic res-
onance imaging (MRI), ultrasound, or computed tomog-
raphy (CT) imaging of the brain, EEG, blood tests, and
neurological testing may all be used to diagnose an un-
derlying condition.
Treatment team
Treatment of abulia is usually part of a program of
general rehabilitation for the symptoms accompanying the
underlying condition. A neurologist or psychiatrist may
lead a treatment team. Other professionals that may be in-
volved include physical therapists, occupational therapists,
recreational therapists, and speech and language therapists.
Treatment
There are no specific treatments for abulia. The un-
derlying condition should be treated such as administering
antidepressants or electroconvulsive therapy to depressed
patients or antipsychotic medications to schizophrenic pa-
tients. Patients who have suffered brain injury due to
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GALE ENCYCLOPEDIA OF NEUROLOGICAL DISORDERS
Acetazolamide
stroke, bleeding, or trauma will benefit from rehabilitation

programs that provide stimulation and attempt to re-teach
skills.
Research has looked at the possibility of treating ab-
ulia with medications that boost the activity of dopamine
throughout the brain, but this is far from becoming a stan-
dard treatment.
Prognosis
The prognosis of abulia depends on the prognosis of
the underlying condition.
Resources
BOOKS
Friedman, Joseph H. “Mood, Emotion, and Thought.” In
Textbook of Clinical Neurology, edited by Christopher G.
Goetz. Philadelphia: W. B. Saunders Company, 2003.
PERIODICALS
Al-Adawi, Samir. “Abulia: The Pathology of ‘Will’ and
Dopaminergic Dysfunction in Brain-Injured Patients.”
Medical Sciences 1 (1999): 27–40.
Nishie, M. “Posterior Encephalopathy Subsequent to
Cyclosporin A Presenting as Irreversible Abulia.” Internal
Medicine 42, no. 8 (1 August 2003): 750–755.
Pantoni, L. “Abulia and Cognitive Impairment in Two Patients
with Capsular Genu Infarct.” Acta Neurologica
Scandinavia 104, no. 3 (1 September 2001): 185–190.
Vijayaraghavan. “Abulia: A Delphi Survey of British
Neurologists and Psychiatrists.” Movement Disorders 17,
no. 5 (September 2002): 1052–1057.
Rosalyn Carson-DeWitt, MD
Acanthocytosis see Bassen-Kornzweig
syndrome

❙
Acetazolamide
Definition
Acetazolamide (a-set-a-ZOLE-a-mide) is a carbonic
anhydrase inhibitor. Carbonic anhydrase is an enzyme that
shifts the rate of reaction to favor the conversion of carbon
dioxide and water into carbonic acid, bicarbonate ions, and
free protons. Carbonic anhydrase activity is key to the reg-
ulation of pH and fluid balance in many different reactions
throughout the body.
Fluid buildup can alter the shape of the eye and cause
pressure on the optic nerve. Clinically, this condition is de-
scribed as glaucoma. Inhibition of the enzymatic work of
carbonic anhydrase activity (e.g., through the action of a
carbonic anhydrase inhibitor) can lower fluid pressure in
the eye.
Purpose
Acetazolamide is used to treat a number of disorders,
including the control of epileptic seizures in those indi-
viduals who suffer epilepsy.
Acetazolamide is also used to treat non-neurological
disorders such as glaucoma (acetazolamide decreases
pressure in the eye), and to reduce the symptoms of edema
(an excess storage of water by the body that leads to lo-
calized swelling or puffiness) and altitude sickness.
Description
Acetazolamide is prescription medication and is
available only with a licensed physician’s prescription. Ac-
etazolamide is available in oral form in extended release
capsules and tablets. Acetazolamide can also be adminis-

tered by injection.
Recommended dosage
For both adults and children the recommended
dosage for use in epilepsy cases is based upon actual body
weight. In all cases, the exact dosage is determined by an
experienced physician and/or pharmacist. In the most
common cases, the normal recommended dosage is 4.5
mg per pound of body weight (10 mg per kg of body
weight) and is administered in multiple (divided) doses de-
livered in the form of tablets or capsules.
Doses must be taken on a regular schedule but indi-
viduals should not double dose to make up for a missed
dose.
When used to control anticonvulsive seizures, aceta-
zolamide doses should not be stopped all at once. In most
cases, physicians usually curtail (gradually lower) the dose
an individual takes over time.
Precautions
As with most prescription medicines, acetazolamide
should stored in a safe place—away from the reach of chil-
dren. Acetazolamide should also be stored in a dry area
away from excessive heat or light. Outdated medicine
(medicines past their expiration date) should be discarded
in a container that is safe from the reach of children.
Women who are pregnant, plan to become pregnant,
or who are breast-feeding infants should inform their
physician of this fact before taking acetazolamide.
Side effects
Unwanted side effects while taking acetazolamide in-
clude drowsiness, fatigue, or a dizzy lightheaded feeling.

Individuals who experience these side effects should not
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3
Acupuncture
Key Terms
Carbonic anhydrase An enzyme that shifts the
rate of reaction to favor the conversion of carbon
dioxide and water into carbonic acid, bicarbonate
ions, and free protons.
Optic nerve The bundle of nerve fibers that carry
visual messages from the retina to the brain.
operate machinery or drive while experiencing these
symptoms. Other common side effects include shortness
of breath.
Acetazolamide can also lead to excessive depletion
(loss) of potassium from the body. To counter this poten-
tial loss, many physicians recommend that patients eat
food or drink beverages such as orange juice to replace
lost potassium. The loss of potassium does not occur in
every case, however, and high levels of potassium can also
be dangerous. Individuals who show signs of potassium
loss—including, but not limited to, dryness of mouth, in-
creased thirst, or muscle cramps—should alert their physi-
cian. Because diet can impact a number of health factors,
individuals should only alter their diet after consulting
their physician.
Individuals who are diabetic and who take acetazo-
lamide may experience elevated sugar levels in their urine
and blood.

Individuals who experience changes in their vision
should also consult their physician.
In some rare cases, individuals may suffer depres-
sion, pains in the area of the kidneys, and bloody or black
tarry stools.
Interactions
Physicians and pharmacists are trained to evaluate the
potential for adverse interactions by prescription drugs with
other drugs. In the case of acetazolamide physicians eval-
uate potential adverse reactions with a range of drugs that
include—but are not limited to—amphetamines, over-the-
counter aspirins, cyclosporine, mood altering drugs (e.g.,
lithium), drugs used to control mental depression, drugs
used to control irregular heartbeats, digoxin, diuretics (also
known as water pills), and vitamins.
Resources
PERIODICALS
Varadkar S., J. S. Duncan, and H. Cross. “Acetazolamide and
Autosomal Dominant Nocturnal Frontal Lobe Epilepsy.”
Epilepsia 44 (July 2003): 986.
OTHER
Medline Plus. U.S. National Library of Medicine and the
National Institutes of Health. < />medlineplus/druginfo/uspdi/202114.html> (May 9, 2004).
ORGANIZATIONS
National Eye Institute. 2020 Vision Place, Bethesda, MD
20892-3655. (301) 496-5248. < />Paul Arthur
❙
Acupuncture
Definition
Acupuncture, one of the main forms of therapy in tra-

ditional Chinese medicine (TCM), has been practiced for
at least 2,500 years. In acupuncture, certain points on the
body are stimulated by the insertion of fine needles. Unlike
the hollow hypodermic needles used in mainstream med-
icine to give injections or to draw blood, acupuncture nee-
dles are solid. The points can be needled between 15° and
90° relative to the skin’s surface, depending on treatment.
Acupuncture is thought to restore health by removing
energy imbalances and blockages in the body. Practition-
ers of TCM believe that there is a vital force or energy
called qi (pronounced “chee”) that flows through the body
and between the skin surface and the internal organs, along
channels or pathways called meridians. There are 12 major
and eight minor meridians. Qi regulates the spiritual, emo-
tional, mental, and physical harmony of the body by keep-
ing the forces of yin and yang in balance. Yang is a
principle of heat, activity, brightness, outwardness, while
yin represents coldness, passivity, darkness, interiority, etc.
TCM does not try to eliminate either yin or yang, but rather
keep them in harmonious balance. Acupuncture may be
used to raise or lower the level of yin or yang in a specific
part of the body in order to restore the energy balance.
Acupuncture was virtually unknown in the United
States prior to President Richard Nixon’s trip to China in
1972. A reporter for the New York Times named James Re-
ston wrote a story for the newspaper about the doctors in
Beijing who used acupuncture to relieve his pain follow-
ing abdominal surgery. By 1993, Americans were making
12 million visits per year to acupuncturists, and spending
$500 million annually on acupuncture treatments. By

1995, there were an estimated 10,000 certified acupunc-
turists practicing in the United States; as of 2000, there
were 20,000. About a third of the credentialed acupunc-
turists in the United States as of 2002 are MDs.
Acupuncture’s record of success has stimulated a
number of research projects investigating its mechanisms
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GALE ENCYCLOPEDIA OF NEUROLOGICAL DISORDERS
Acupuncture
Key Terms
Cardiac tamponade A condition in which blood
leaking into the membrane surrounding the heart puts
pressure on the heart muscle, preventing complete
filling of the heart’s chambers and normal heartbeat.
Electroacupuncture A variation of acupuncture in
which the practitioner stimulates the traditional
acupuncture points electronically.
Endorphins A group of peptide compounds re-
leased by the body in response to stress or traumatic
injury. Endorphins react with opiate receptors in the
brain to reduce or relieve pain.
Hyperemesis gravidarum Uncontrollable nausea
and vomiting associated with pregnancy. Acupunc-
ture appears to be an effective treatment for women
with this condition.
Meridians In traditional Chinese medicine, a network
of pathways or channels that convey qi (also sometimes
spelled “ki”), or vital energy, through the body.
Moxibustion A technique in traditional Chinese

medicine that involves burning a “Moxa,” or cone of
dried wormwood leaves, close to the skin to relieve
pain. When used with acupuncture, the cone is
placed on top of the needle at an acupuncture point
and burned.
Neurotransmitter A chemical in the brain that
transmits messages between neurons, or nerve cells.
Opioids Substances that reduce pain and may in-
duce sleep. Some opioids are endogenous, which
means that they are produced within the human
body. Other opioids are produced by plants or for-
mulated synthetically in the laboratory.
Pneumothorax A condition in which air or gas is
present in the chest cavity.
Qi The Chinese term for energy, life force, or vital
force.
Yin and yang In traditional Chinese medicine and
philosophy, a pair of opposing forces whose harmo-
nious balance in the body is necessary to good
health.
as well as its efficacy. Research has been funded not only
by the National Center for Complementary and Alternative
Medicine (NCCAM), but also by the National Institute on
Alcohol Abuse and Alcoholism (NIAAA), the National
Institute of Dental Research, the National Institute of Neu-
rological Disorders and Stroke (NINDS), and the National
Institute on Drug Abuse. In 1997, a consensus panel of the
National Institutes of Health (NIH) presented a report in
which it described acupuncture as a sufficiently promising
form of treatment to merit further study. In 2000, the

British Medical Association (BMA) recommended that
acupuncture should be made more readily available
through the National Health Service (NHS), and that fam-
ily doctors should be trained in some of its techniques.
Purpose
The purpose of acupuncture in TCM is the rebalanc-
ing of opposing energy forces in different parts of the
body. In Western terms, acupuncture is used most com-
monly as an adjunctive treatment for the relief of chronic
or acute pain. In the United States, acupuncture is most
widely used to treat pain associated with musculoskeletal
disorders, but it has also been used in the treatment of
headaches, other painful disorders, and nausea and vom-
iting. In addition to these disorders, acupuncture has been
used to treat a variety of disorders such as asthma, infer-
tility, depression, anxiety, HIV infection, and fibromyal-
gia, although its efficacy in relieving these disorders is
largely unproven. Acupuncture should not be used to treat
traumatic injuries and other emergency conditions requir-
ing immediate surgery. Also, while it appears to have ben-
efits in relieving symptoms such as pain under the proper
circumstances, it has not been shown to alter the underly-
ing course of a disease.
The exact mechanism by which acupuncture works is
not known. Studies have demonstrated a variety of physi-
ologic effects such as release in the brain of various chem-
icals and hormones, alteration of immune function, blood
pressure, and body temperature.
Precautions
The risk of infection in acupuncture is minimal if the

acupuncturist uses sterile disposable needles. In the United
States, the Food and Drug Administration (FDA) man-
dates the use of sterilized needles made from nontoxic ma-
terials. The needles must be clearly labeled as having their
use restricted to qualified practitioners.
Patients should also inquire about the practitioner’s
credentials. People who would prefer to be treated by an
MD or an osteopath can obtain a list of licensed physicians
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5
Acupuncture
LI
BL
ST
CV
GV
SI
TW
BL
LU
HE
GB
SP
LV
PE
KI
Traditional Chinese medicine teachings state that channels of energy flow throughout the body, and that disease is caused
by too much or too little flow of energy along these channels. Points along the channels, called meridians, are manipulated
in acupuncture. In the illustration, points are shown on the bladder (BL), conception vessel (CV), gallbladder (GB), govern-

ing vessel (GV), heart (HE), kidney (KI), large intestine (LI), liver (LV), lung (LU), pericardium (PE), small intestine (SI), spleen
(SP), stomach (ST), and triple warmer (TW) meridians. (Illustration by Electronic Illustrators Group.)
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GALE ENCYCLOPEDIA OF NEUROLOGICAL DISORDERS
Acupuncture
Conception vessel
Stomach meridian
Large intestine meridian
Gallbladder meridian
Governor vessel
Bladder meridian
Triple burner meridian
Small intestine meridian
Acupuncture sites and meridians on the face and neck. (Illustration by Hans & Cassady, Inc.)
who practice acupuncture in their area from the American
Academy of Medical Acupuncture. With regard to non-
physician acupuncturists, 31 states have established train-
ing standards that acupuncturists must meet in order to be
licensed in those states. In Great Britain, practitioners
must qualify by passing a course offered by the British
Acupuncture Accreditation Board.
People seeking acupuncture treatment should provide
the practitioner with the same information about their
health conditions and other forms of treatment that they
would give their primary care doctor.
As is true with other forms of medical treatment, a
minority of patients do not respond to acupuncture. The
reasons for nonresponsiveness are not known at the pres-
ent stage of research.

Description
In traditional Chinese practice, the needles are twirled
or rotated as they are inserted. Many patients feel nothing
at all during this procedure, while others experience a
prickling or aching sensation, and still others a feeling of
warmth or heaviness.
The practitioner may combine acupuncture with mox-
ibustion to increase the effectiveness of the treatment.
Moxibustion is a technique in which the acupuncturist
lights a small piece of wormwood, called a moxa, above
the acupuncture point above the skin. When the patient be-
gins to feel the warmth from the burning herb, it is re-
moved. Cupping is another technique that is a method of
stimulation of acupuncture points by applying suction
through a metal, wood, or glass jar, and in which a partial
vacuum has been created. Cupping produces blood con-
gestion at the site, and the site is thus stimulated.
In addition to the traditional Chinese techniques of
acupuncture, the following are also used in the United
States:
• Electroacupuncture. In this form of acupuncture, the tra-
ditional acupuncture points are stimulated by an elec-
tronic device instead of a needle.
• Japanese meridian acupuncture. Japanese acupuncture
uses thinner, smaller needles, and focuses on the merid-
ians rather than on specific points along their course.
• Korean hand acupuncture. Traditional Korean medicine
regards the hand as a “map” of the entire body, such that
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GALE ENCYCLOPEDIA OF NEUROLOGICAL DISORDERS

7
Acupuncture
any part of the body can be treated by stimulating the
corresponding point on the hand.
• Western medical acupuncture. Western physicians
trained in this style of acupuncture insert needles into so-
called trigger points in sore muscles, as well as into the
traditional points used in Chinese medicine.
• Ear acupuncture. This technique regards the ear as hav-
ing acupuncture points that correspond to other parts of
the body. Ear acupuncture is often used to treat substance
abuse and chronic pain syndromes.
A standard acupuncture treatment takes between 45
minutes to an hour and costs between $40 and $100, al-
though initial appointments often cost more. Chronic con-
ditions usually require 10 treatment sessions, but acute
conditions or minor illnesses may require only one or two
visits. Follow-up visits are often scheduled for patients
with chronic pain. As of 2000, about 70–80% of health in-
surers in the United States reimbursed patients for
acupuncture treatments.
Preparation
Apart from a medical history and physical examina-
tion, no specific preparation is required for an acupuncture
treatment. In addition to using sterile needles, licensed
acupuncturists will wipe the skin over each acupuncture
point with an antiseptic solution before inserting the needle.
Aftercare
No particular aftercare is required, as the needles
should not draw blood when properly inserted. Many pa-

tients experience a feeling of relaxation or even a pleasant
drowsiness after the treatment. Some patients report feel-
ing energized.
Risks
Most complications from acupuncture fall into one of
three categories: infections, most often from improperly
sterilized needles; bruising or minor soft tissue injury; and
injuries to muscle tissue. Rarely, serious side effects from
improper application of the needle may result in pneu-
mothorax and cardiac tamponade.
Normal results
Normal results from acupuncture are relief of pain
and/or improvement of the condition being treated.
Abnormal results
Abnormal results from acupuncture include infection,
a severe side effect, or worsening of the condition being
treated.
Resources
BOOKS
Pelletier, Kenneth R., MD. “Acupuncture: From the
Yellow Emperor to Magnetic Resonance Imaging
(MRI).” Chapter 5 in The Best Alternative
Medicine. New York: Simon and Schuster,
2002.
Reid, Daniel P. Chinese Herbal Medicine. Boston, MA:
Shambhala, 1993.
Svoboda, Robert, and Arnie Lade. Tao and Dharma: Chinese
Medicine and Ayurveda. Twin Lakes, WI: Lotus Press,
1995.
PERIODICALS

Cerrato, Paul L. “New Studies on Acupuncture and
Emesis (Acupuncture for Relief of Nausea
and Vomiting Caused by Chemotherapy).” Contemporary
OB/GYN 46 (April 2001):
749.
Kemper, Kathi J., et al. “On Pins and Needles—Pediatric Pain:
Patients’ Experience with Acupuncture.” Pediatrics 105
(April 2000): 620–633.
Kirchgatterer, Andreas. “Cardiac Tamponade Following
Acupuncture.” Chest 117 (May 2000):
1510–1511.
Nwabudike, Lawrence C., and Constantin Ionescu-
Tirgoviste. “Acupuncture in the Treatment of
Diabetic Peripheral Neuropathy.” Diabetes 49
(May 2000): 628.
Silvert, Mark. “Acupuncture Wins BMA Approval (British
Medical Association).” British Medical Journal 321 (July
1, 2000): 637–639.
Vickers, Andrew. “Acupuncture (ABC of Complementary
Medicine).” British Medical Journal 319 (October 9,
1999): 704–708.
ORGANIZATIONS
American Academy of Medical Acupuncture/Medical
Acupuncture Research Organization. 5820 Wilshire
Boulevard, Suite 500, Los Angeles, CA 90036.
(800) 521-2262 or (323) 937-5514; Fax: (323)
937-0959. (May 9, 2004.) <ical
acupuncture.org>.
American Association of Oriental Medicine. 433 Front
Street, Catasaqua, PA 18032. (610) 266-1433;

Fax: (610) 264-2768. (May 9, 2004.) <m.
org>.
National Center for Complementary and Alternative Medicine
(NCCAM) Clearinghouse. P.O. Box 7923, Gaithersburg,
MD 20898. (888) 644-6226; TTY: (866) 464-3615; Fax:
(866) 464-3616. (May 9, 2004.) <am.
nih.gov>.
Rebecca Frey, PhD
Rosalyn Carson-DeWitt, MD
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GALE ENCYCLOPEDIA OF NEUROLOGICAL DISORDERS
Acute disseminated encephalomyelitis
Key Terms
Encephalitis Inflammation of the brain, usually
caused by a virus. The inflammation may interfere
with normal brain function and cause seizures,
sleepiness, confusion, personality changes, weak-
ness in one or more parts of the body, and even
coma.
Myelin A fatty sheath surrounding nerves through-
out the body that helps them conduct impulses
more quickly.
❙
Acute disseminated
encephalomyelitis
Definition
Acute disseminated encephalomyelitis (ADE) is a
neurological disorder involving inflammation of the brain
and spinal cord. A hallmark of the disorder is damage to

the myelin sheath that surrounds the nerve fibers in the
brain, which results in the inflammation.
Description
Acute disseminating encephalomyelitis was first de-
scribed in the mid-eighteenth century. The English physi-
cian who first described the disorder noted its association
with people who had recently recovered from smallpox.
Symptoms often develop without warning. As well, men-
tal disorientation can occur. The disorder is also known as
postinfectious encephalomyelitis and immune-mediated
encephalomyelitis. The nerve demyelination that occurs in
ADE also occurs in multiple sclerosis. However, the two
maladies differ in that multiple sclerosis is long lasting and
can recur over time, while ADE has a monophasic course,
meaning that once it is over, further attacks rarely occur.
Demographics
ADE can occur in both children and adults, although
it occurs more commonly in children. ADE is not rare, ac-
counting for approximately 30% of all cases of encephali-
tis (brain inflammation).
Causes and symptoms
Acute disseminating encephalomyelitis can occur as a
consequence of a bacterial or viral infection (including
HIV), following recovery from infection with the malarial
protozoan, or as a side effect of vaccination or another in-
oculation. ADE is usually a consequence of a viral illness,
and occurs most often after measles, followed by rubella,
chicken pox, Epstein-Barr, mumps and pertussis (whoop-
ing cough). Typically, symptoms appear two to three weeks
after the precipitating infection or immunization. Alterna-

tively, ADE may develop with no known associations.
Despite the different causes, the symptoms that de-
velop are similar. A number of non-specific symptoms,
which vary from one person to another, include
headache, stiff neck, fever, vomiting, and weight loss.
These symptoms are quickly followed by lethargic be-
havior, seizures, hallucinations, sight difficulties, and
even coma. Paralysis can occur in an arm or leg (mono-
paresis) or along an entire side of the body (hemiplegia).
These symptoms can last a few weeks to a month. In
some people, symptoms can progress from the appearance
of symptoms to coma and death in only a few days. Brain
damage is largely confined to the white matter. Micro-
scopic examination will typically reveal invasion of white
blood cells into small veins. The nerve myelin damage oc-
curs in the regions where the white blood cells accumu-
late. Examination of the brains of patients who have died
of the disorder has not yielded consistent results. Some
brains appear normal, while others display the nerve dam-
age and white blood cell congestion.
Diagnosis
Diagnosis is made based on the above symptoms and
the patient’s medical history (i.e., recent infection or vac-
cination). In the early stages of the disorder, diagnosis can
be confused with diseases including acute meningitis,
acute viral encephalitis, and multiple sclerosis. Often, the
latter can be ruled out using magnetic resonance imag-
ing (MRI) and examination of the cerebrospinal fluid
(CSF). Typically, in acute disseminating en-
cephalomyelitis, CSF contains abnormally elevated levels

of white blood cells and protein; and magnetic resonance
imaging can reveal brain alterations.
Treatment team
The treatment team typically consists of a primary
care physician and, when hospitalization is necessary,
nurses and specialized medical care personnel.
Treatment
Corticosteroid medication is often prescribed in
order to lessen the nerve inflammation. Use of high doses
of steroids can often produce a rapid diminishing of the
symptoms. Other kinds of treatment depend on the nature
of the symptoms that develop. Supportive care includes
keeping a patient comfortable and hydrated.
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9
Adrenoleukodystrophy
Recovery and rehabilitation
Persons recovering from acute disseminated en-
cephalomyelitis need time to recover their normal con-
sciousness and movements. Problems with memory,
especially short-term memory, may be present. The re-
covering person sometimes has trouble controlling their
emotions and is easily frustrated. Frequent periods of rest,
alternating with shorter periods of mental and physical ex-
ercise are prescribed during initial recovery. The maxi-
mum possible recovery of brain and motor function may
take a period of weeks or months.
Clinical trials
There are no clinical trials for the study of ADE re-

cruiting patients or being planned in the United States, as
of January 2004. However, organizations such as the Na-
tional Institute for Neurological Disorders and Stroke un-
dertake and fund studies on disorders that involve damage
to the myelin sheath of nerve cells. By understanding the
nature of the disorders, it is hoped that detection can be
improved and strategies will evolve to prevent or reverse
the nerve damage.
Prognosis
Prognosis varies from person to person. Some patients
may recover fully, with no residual effects. Others may
have some residual damage. Seldomly, ADE is fatal. Early
detection and treatment improves a patient’s outlook.
Special concerns
Although the incidence of ADE occurring after vac-
cination is rare, in recent years, public debate has led some
parents to choose that their children not receive the rec-
ommended childhood vaccinations. The American Acad-
emy of Pediatrics asserts that, despite concerns about
vaccine safety, vaccination is far safer than accepting the
risks for the diseases that the vaccines prevent.
Resources
BOOKS
Icon Health Publications. The Official Patient’s Sourcebook on
Acute Disseminated Encephalomyelitis: A Revised and
Updated Directory for the Internet Age. San Diego: Icon
Group International, 2002.
PERIODICALS
Anlar, B., C. Basaran, G. Kose, A. Guven, S. Haspolat,
A. Yakut, A. Serdaroglu, N. Senbil, H. Tan, E.

Karaagaoglu, and K. Oguz. “Acute disseminated
encephalomyelitis in children: outcome and prognosis.”
Neuropediatrics (August 2003): 194–199.
Brass, S. D., Z. Caramanos, C. Santos, M. E. Dilenge,
Y. Lapierre, and B. Rosenblatt. “Multiple sclerosis vs
acute disseminated encephalomyelitis in childhood.”
Pediatric Neurology (September 2003): 227–231.
Koibuchi, T., T. Nakamura, T. Miura, T. Endo, H. Nakamura,
T. Takahashi, H. S. Kim, Y. Wataya, K. Washizaki,
K. Yoshikawa, and A. Iwamoto. “Acute disseminated
encephalomyelitis following Plasmodium vivax malaria.”
Journal of Infection and Chemotherapy (September
2003): 254–256.
Narciso, P., S. Galgani, B. Del Grosso, M. De Marco, A.
De Santis, P. Balestra, V. Ciapparoni, and V. Tozzi. “Acute
disseminated encephalomyelitis as manifestation of pri-
mary HIV infection.” Neurology (November 2001):
1493–1496.
OTHER
“Acute Disseminated Encephalomyelitis Information Page.”
National Institute of Neurological Disorders and Stroke.
< />disorders/acute_encephalomyelitis_doc.htm> (January
26, 2004).
ORGANIZATIONS
National Institute for Neurological Diseases and Stroke
(NINDS). 6001 Executive Boulevard, Bethesda, MD
20892. (301) 496-5751 or (800) 352-9424.
<>.
National Organization for Rare Disorders. 55 Kenosia Avenue,
Danbury, CT 06813-1968. (203) 744-0100 or (800) 999-

6673; Fax: (203) 798-2291.
<>.
Brian Douglas Hoyle, PhD
ADHD see Attention deficit hyperactivity
disorder
❙
Adrenoleukodystrophy
Definition
Adrenoleukodystrophy (ALD) is a progressive con-
dition that affects both the adrenal glands (located atop the
kidneys and responsible for the production of adrenalin)
and myelin (the substance that insulates the nerves in the
brain, spinal cord, and the limbs).
Description
First described in the early 1900s, adrenoleukodys-
trophy was originally called Schilder-Addision disease.
“Adreno” refers to the adrenal glands, “leuko” is the Greek
word for white (myelin is the main component of the
white matter in the brain and spinal cord), and “dystrophy”
means impaired growth. This disease affects the adrenal
glands and the growth of the myelin.
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GALE ENCYCLOPEDIA OF NEUROLOGICAL DISORDERS
Adrenoleukodystrophy
Key Terms
Adrenal insufficiency Problems with the adrenal
glands that can be life threatening if not treated.
Symptoms include sluggishness, weakness, weight
loss, vomiting, darkening of the skin, and mental

changes.
Central nervous system (CNS) The CNS is com-
posed of the brain, the cranial nerves, and the
spinal cord. It is responsible for the coordination
and control of all body activities.
Leukodystrophy A disease that affects the white
matter called myelin in the CNS.
Myelin A fatty sheath surrounding nerves in the
peripheral nervous system that helps them conduct
impulses more quickly.
Peroxisomes Tiny structures in the cells that
break down fats so that the body can use them.
Very long chain fatty acid (VLCFA) A type of fat
that is normally broken down by the peroxisomes
into other fats that can be used by the body.
Types of ALD
There are three types of ALD, each with a different
severity of symptoms and age of onset of ALD. All vary-
ing degrees of severity have been seen within the same
family. Therefore, a family who has many mildly affected
members could still have a more severely affected mem-
ber. Some patients do not fall neatly into one of the three
categories, and instead fall somewhere in between. Each
type is given a different name, although all have mutations
(changes in the genetic code) in the same gene and the
same type of inheritance.
The most severe form of ALD is called childhood
ALD. About 35% of people with ALD have this type.
These children usually have normal development in the
first few years of life. Symptoms typically begin between

four and eight years of age. Very rarely is the onset before
the age of three or after the age of 15. In some boys, the
first symptom may be seizures. Other children become
hyperactive and have behavioral problems that may ini-
tially be diagnosed as attention deficit/hyperactivity
disorder (ADHD). Early signs may also include poor
school performance due to impaired vision that is not cor-
rectable by eyeglasses. Although these symptoms may last
for a few months, other more severe problems develop.
These include increasing problems with schoolwork and
deterioration in handwriting and speech. Affected children
usually develop clumsiness, difficulty in reading and com-
prehension of written material, aggressive or uninhibited
behavior, and various personality and behavioral changes.
Most affected boys have problems with their adrenal
glands by the time their first symptoms are noticed.
A milder form of ALD, called adrenomyeloneuropa-
thy (AMN), usually has a symptom onset at the age of 20
or later. Approximately 40–45% of people with ALD have
AMN. The first symptoms are typically a progressive stiff-
ness and weakness in the legs. Problems with urination
and sexual function may also develop. Symptoms slowly
progress over many years. Less than 20% of men with
AMN will develop significant brain involvement that leads
to cognitive and behavioral problems that are severe and
may cause a shortened lifespan. About 70% of men with
AMN will have problems with their adrenal glands when
other symptoms are initially noticed.
A third type of ALD is called Addison disease and af-
fects about 10% of all of those with ALD. In this condi-

tion, people do not have the neurologic symptoms
associated with ALD and AMN, but they do have prob-
lems resulting from adrenal insufficiency. Symptoms typ-
ically begin between two years of age and adulthood. The
first symptoms are often vomiting, weakness, or coma.
People with Addision disease may or may not have darker
skin. Many who are initially diagnosed with Addison dis-
ease will later develop symptoms of AMN.
In female carriers of ADL, about 20% will develop
mild to moderate progressive stiffness and weakness in the
legs and sometimes problems with urination. Rarely do
they develop adrenal insufficiency. Symptoms in women
generally do not begin before middle age.
Demographics
ALD is found in all ethnic groups. About one in every
100,000 people suffers from ALD. Because the most se-
vere form, called classic ALD, is X-linked, many more
males than females are affected. Women are carriers of this
X-linked form of the disease and may exhibit no or only
mild symptoms. Another form of the disease is called
neonatal ALD; this form of ALD is not X-linked and
therefore both male and female babies exhibit symptoms.
An adult-onset type of the disease is commonly called
adrenomyeloneuropathy.
Causes and symptoms
ALD causes problems in the peroxisomes, tiny cellu-
lar structures that are involved in breaking down large
molecules of fats into smaller ones that can be used by the
body. In ALD, the peroxisomes cannot break down a type
of fat called very long chain fatty acid (VLCFA). As a re-

sult, VLCFAs accumulate throughout the body, particu-
larly in the brain and adrenal glands. This accumulation
interferes with the adrenal glands’ conversion of choles-
terol into steroids, and prompts deterioration of the myelin
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