percent of spinal cord injuries occur in people who
are between the ages of 15 and 30. Many of these
ACCIDENTAL INJURIESare preventable. Many of the
illnesses that threatened not only nervous system
function but often life itself—POLIOMYELITIS,
ENCEPHALITIS, MENINGITIS—in previous generations
are now either preventable or treatable.
HEALTH CONDITIONS
INVOLVING THE NERVOUS SYSTEMALZHEIMER’S DISEASE AMYOTROPHIC LATERAL SCLEROSIS
APHASIA (ALS)
APRAXIA ATAXIA
ATHETOSIS AUTISM
BELL’S PALSY BRAIN TUMOR
BRAIN HEMORRHAGE CEREBRAL PALSY
CHOREA cognitive dysfunction
CONCUSSION DELIRIUM
DEMENTIA developmental disabilities
DYSKINESIA ENCEPHALITIS
ENCEPHALOPATHY GUILLAIN-BARRÉ SYNDROM
HEADACHE HERNIATED NUCLEUS PULPOSUS
HUNTINGTON’S DISEASE HYDROCEPHALY
LEARNING DISORDERS memory impairment
MENINGITIS MULTIPLE SCLEROSIS
MYASTHENIA GRAVIS MYOCLONUS
MYOTONIA NARCOLEPSY
NEURALGIA NEURAL TUBE DEFECTS
NEURITIS NEUROFIBROMATOSIS
NEUROPATHY ORGANIC BRAIN SYNDROME
PARALYSIS PARESTHESIA
PARKINSON’S DISEASE POLIOMYELITIS
RESTLESS LEGS SYNDROME SEIZURE DISORDERS
SPINA BIFIDA SPINAL CORD INJURY
TIC TOURETTE’S SYNDROME
TRAUMATIC BRAIN INJURY(TBI) TREMOR DISORDERS
Systemic health conditions shift to the forefront
of concern with the approach of late age. CARDIO-
VASCULAR DISEASE(CVD), endocrine disorders, pul-
monary disease, and disorders of METABOLISM
arising from LIVER and kidney disease become
more prevalent with advancing age. All of these
conditions have the potential to affect nervous
system function. STROKE, a consequence of cardio-
vascular disease, is the leading cause of disability
resulting from damage to the brain. Metabolic dis-
orders such as chronic CIRRHOSISand DIABETESmay
disrupt the body’s biochemical balances to the
extent of creating brain dysfunction (ENCEPHALOPA-
THY). Health conditions that directly affect the
nervous system also become more frequent with
increasing age. The most common—and dis-
abling—such conditions are Alzheimer’s disease,
Parkinson’s disease, andDEMENTIA. Alzheimer’s dis-
ease alone affects as many as 50 percent of people
age 85 and older.
Traditions in Medical History
The earliest medical writings of Eastern and West-
ern physicians document nervous system condi-
tions such as epilepsy (SEIZURE DISORDERS) and
surgical treatments that involved boring through
the skull, probably to relieve pressure resulting
from head trauma. Healed wounds in skulls,
clearly made by intent, remain as archaeological
evidence that physicians of antiquity were some-
what sophisticated, as well as successful, in their
methods. Mummified remains reveal that
poliomyelitis—which approached worldwide erad-
ication in 2005 through vaccination efforts, with
the exception of a few pockets where the disease
remained endemic—was fairly common among
ancient Mesopotamians and Egyptians.
The Greek physician and philosopher Hip-
pocrates, the father of modern medicine, was the
first to determine the brain’s responsibility for
consciousness and control of the body. The inabil-
ity to directly explore the structure and function
of the brain resulted in centuries of misunder-
standings, however. The first accurate representa-
tions emerged when in 1543 Andreas Vesalius
(1514–1564) published the landmark manuscript
De humani corporis fabrica libri septum,more famil-
iarly known today as The Fabric of the Human Body.
The manuscript presented the first drawings of the
human brain based on dissection and physical
examination.
Breakthrough Research and Treatment Advances
Today some of the greatest advances in under-
standing of brain and nervous system structure
and function come from research in genetics and
molecular medicine. HUNTINGTON’S DISEASEwas one
of the first neurologic disorders for which
researchers established a conclusive genetic foun-
dation. In the 1990s researchers uncovered muta-
tions in genes responsible for Parkinson’s disease,
Alzheimer’s disease, and Lewy body dementia.218 The Nervous System