Glossary

Alzheimer's disease: A progressive and fatal brain disease that is the most common form of dementia in older persons; as it destroys brain cells, the disease affects many areas of memory and cognitive function. There is no current cure, though treatment for symptoms can improve life for patients living with Alzheimer's.
amyotrophic lateral sclerosis (ALS, motor neuron disease, Lou Gehrigs disease): A degenerative disorder affecting the motor neuron cells and the motor tracts in the brain and spinal cord.
angiogram: In this imaging test used to study vascular conditions, a physician threads a thin, flexible tube called a catheter into veins (venogram) and arteries (arteriogram) to inject a contrast agent or “dye” that makes blood flowing through blood vessels visible on an x-ray.
aphasia: An acquired abnormality in the production or comprehension of language.
arteries: Blood vessels that carry oxygenated blood to the organs.
atherosclerosis: Thickening of the arterial wall of blood vessels due to deposition of lipids (fats) and blood clots.
atony: A lack of muscle tone, usually leading to temporary debilitation.
atrial fibrillation: An abnormal rhythm of the heart that can result in an increased risk of stroke due to the formation of emboli (blood clots) in the heart.
atrophy: Shrinkage in size of a particular structure, such as muscle groups or the brain.
aura: Symptoms that occur prior to a particular neurological problem (such as seizure or migraine) that serve as a warning that an abnormal spell may follow. Includes disturbances in vision, smell or perception.
autoimmune: An abnormal response of the immune system, causing the body to act against its own tissues, cells, and/or organs. Autoimmune disorders may be the root of many diseases.
axon: The inner core of peripheral nerves.
BAER (brainstem auditory evoked response): Measures function of central nervous system, including pathway from brainstem.
basal ganglia: A series of structures located deep in the brain responsible for motor movements.
benign: Usually used in the context of referring to tumors that are not cancerous.
blepharospasm: Involuntary closure of the eyes and lids.
bradykinesia: Slowing of motor movements due to dysfunction of the basal ganglia and related structures.
CAT Scan (computerized axial tomography): A specialized X-ray examination that is often used to visualize the brain and spinal structures.
cataplexy: A symptom characterized by the sudden loss of postural tone, often resulting in the individual falling to the floor. Cataplexy is often part of the narcolepsy complex.
central nervous system: Refers to the brain and the spinal cord.
cerebral aneurysm: A defect that results in weakness in the wall of a blood vessel that can lead to bleeding in the brain.
cerebrospinal fluid: The fluid that surrounds the brain and the spinal cord.
cerebrovascular disease: Disorders that affect the blood vessels that supply the brain; may result in a stroke.
clonus: Brisk increase in tone with involuntary movements that result in dysfunction of the corticospinal tracts.
cluster headache: A syndrome that is more common in males resulting in one-sided, severe pain around the eye; usually occurs at night and is associated with nasal stuffiness and tearing of the eye.
coma: A state of unconsciousness in which patients lie unresponsive with the eyes closed.
corticospinal tract: The nervous system structures that begin in the brain and travel to the motor neuron cell to innervate the motor nerves.
deep tendon reflexes: Deep muscle stretch reflexes (such as the knee jerk) obtained by tapping on the tendons.
dementia: An acquired loss of cognitive function that may affect language, attention, memory, personality, and abstract reasoning.
demyelinating: An inflammatory process that disrupts the myelin coating of nervous system structures.
echocardiogram: A diagnostic test to detect abnormalities of the heart using an ultrasound probe to image the cardiac structures.
edema: Swelling; fluid is retained resulting in swollen tissues.
EEG (electroencephalography): Diagnostic test used to study brain wave activity; useful in the evaluation of seizure disorders.
EMG/NCV (electromyography/nerve conduction study): A test used to diagnose disorders in nerves and muscles in which a small needle is placed in the muscle (EMG) to study electrical conduction (NCV); results are seen on an oscilloscope screen and compared to normal values.
encephalitis: Inflammation or infection involving the brain.
evoked potentials: A series of electophysiologic tests that help to evaluate the function of specific elements of the nervous system involved in Multiple Sclerosis.
fasciculation: Twitching of the muscles seen in diseases involving the peripheral nervous system.
gadolinium: A contrast agent given intravenously during MRI (magnetic resonance imaging) to increase visualization of specific abnormalities.
hemiparesis: Weakness that affects one side of the body.
hemorrhage: Bleeding (such as in brain hemorrhage).
HIV (human immunodeficiency virus): Virus that affects the immune system and causes the disease known as AIDS (acquired immunodeficiency disorder).
ischemia: Lack of blood flow (such as in ischemic stroke).
lacunar: A subtype of stroke that affects the deeper parts of the brain and involves the tiny perforating arteries.
lumbar puncture (also known as a spinal tap): A procedure that involves removing some of the cerebrospinal fluid from the base of the spine; a physician uses a local anesthetic on the skin and soft tissues in the lower back before using a syringe to obtain cerebrospinal fluid from the spinal area.
lyme disease: A disease affecting the joints, nervous system, and heart that is transmitted by the deer tick; caused by a parasite known as Borrelia.
malignant: Usually refers to tumors that are cancerous; may refer to a disease state that has a debilitating unremitting course.
meningitis: Inflammation or infection of the meninges (the coverings of the brain).
metastatic: Usually used to describe cancerous lesions that spread to other organs in the body.
migraine: A headache syndrome characterized by throbbing, usually one-sided pain that may be associated with nausea, vomiting, and visual disturbances.
motor neuron cells: The cells located in the spinal cord that give rise to the nerves that supply the muscles.
MRI (magnetic resonance imaging): A technique that utilizes the properties of magnetic fields to provide images of the body (click here for additional information on MRI procedures).
multi-infarct dementia: A dementia that is caused by the cumulative affect of having had many strokes in the brain.
muscular dystrophy: A congenital (hereditary) disorder of the muscles resulting in weakness and muscle dysfunction.
myasthenia gravis: A disorder affecting the space between the nerve and the muscle (neuromuscular junction) that results in transient motor weakness of the face and limbs; due to an autoimmune process affecting the chemical Acetylcholine.
myelin: The outer, lipid-rich (fatty) layer that covers nerves and nervous system pathways in the brain and spinal cord.
myopathy: A disease resulting in muscle dysfunction that usually causes weakness and atrophy.
narcolepsy: A syndrome that is often hereditary; characterized by repeated attacks of sudden sleep that may be associated with other specific abnormalities making up the narcolepsy complex.
neurons: The nerve cells of the brain that carry out neurological function.
NPH (normal pressure hydrocephalus): Increase in pressure within the ventricles of the brain, causing dementia, gait difficulties, and urinary incontinence.
nystagmus: The jerking to and fro movement of the eyes that occurs when disorders affect the control of eye movement.
paraneoplastic: Disorders that occur due to the remote effects of cancer, such as through the mechanism of hormonal or antibody production.
paresthesias: Unusual sensory symptoms of tingling, numbness, or other abnormal feelings of sensation.
peripheral nervous system: Refers to the nerves and muscular structures.
photophobia (literally fear of light): used to describe condition when bright light is bothersome to individuals; often occurs in syndromes such as migraine headache.
plaque: The lesion that occurs in the white matter of the brain due to demyelination; also refers to the matter that builds up on the inner walls of arteries when substances that circulate in the blood (like fat and cholesterol) accumulate and potentially clog arteries.
prophylactic: Used to describe medications or treatments that are preventative in the treatment of disease.
ptosis: Drooping of the eyelids due to weakness of the muscles responsible for keeping the lids open.
radiculopathy: Irritation and inflammation of one of the nerve roots in the vicinity of the spinal column.
REM (rapid eye-movement sleep): The stage of sleep that is characterized by decreased muscle tone, rapid eye movements, and dreaming.
rigidity: Stiffness in the limbs or body due to dysfunction of the basal ganglia and related structures.
sciatic nerve: A large nerve in the lumbar-sacral spinal region that is composed of multiple nerve roots that supply the lower extremities.
seizure: The abnormal electrical discharge of brain cells (neurons) that results in a transient disturbance in brain function.
SEP (somatosensory Evoked Response): Measures function of central nervous system, including pathway from the extremities.
serotonin: An important neurotransmitter (communicates information chemically between brain cells) that is involved in pain disorders and emotional perceptions.
sleep apnea: A disorder that results in apnea (cessation of breathing) during sleep, often due to obstruction of the upper airway.
spasticity: Body stiffness involving the limbs that results from dysfunction of the corticospinal tracts.
spinal stenosis: A syndrome that results in narrowing of the dimensions of the spinal canal due to disc disease, bony changes, ligamentous thickening, and congenital factors.
status epilepticus: Seizures that continue for more than 20 minutes without an intervening period of responsiveness.
subarachnoid hemorrhage: Bleeding in the area surrounding the brain; usually a result of the rupturing of a cerebral aneurysm in the brain.
tensilon test: In this diagnostic test used to confirm Myasthenia Gravis disease, a substance that interferes with the breakdown of acetycholine is injected intravenously and the response is monitored.
TIA (transient ischemic attack): When neurological symptoms occur due to transient interruption of the blood flow to the brain.
torticollis: Involuntary turning of the neck to one side; can be seen in disorders of the basal ganglia.
toxoplasmosis: A parasitic disease that affects the brain; occurs in patients who are immunosuppressed (such as individuals with AIDS).
VER (visual evoked responses): Measures function of central nervous system, including the pathway from optic tract.
vertebrae: Bones that make up the spinal column.
vertigo: Dizziness or imbalance in an individual that often has a spinning or rotational component.
vestibular system: The parts of the nervous system that control equilibrium and balance.
white matter: The lipid-rich myelinated portion of the brain and spinal cord.

Alzheimer's disease: A progressive and fatal brain disease that is the most common form of dementia in older persons; as it destroys brain cells, the disease affects many areas of memory and cognitive function. There is no current cure, though treatment for symptoms can improve life for patients living with Alzheimer's.

amyotrophic lateral sclerosis (ALS, motor neuron disease, Lou Gehrigs disease): A degenerative disorder affecting the motor neuron cells and the motor tracts in the brain and spinal cord.

angiogram: In this imaging test used to study vascular conditions, a physician threads a thin, flexible tube called a catheter into veins (venogram) and arteries (arteriogram) to inject a contrast agent or “dye” that makes blood flowing through blood vessels visible on an x-ray.

aphasia: An acquired abnormality in the production or comprehension of language.

arteries: Blood vessels that carry oxygenated blood to the organs.

atherosclerosis: Thickening of the arterial wall of blood vessels due to deposition of lipids (fats) and blood clots.

atony: A lack of muscle tone, usually leading to temporary debilitation.

atrial fibrillation: An abnormal rhythm of the heart that can result in an increased risk of stroke due to the formation of emboli (blood clots) in the heart.

atrophy: Shrinkage in size of a particular structure, such as muscle groups or the brain.

aura: Symptoms that occur prior to a particular neurological problem (such as seizure or migraine) that serve as a warning that an abnormal spell may follow. Includes disturbances in vision, smell or perception.

autoimmune: An abnormal response of the immune system, causing the body to act against its own tissues, cells, and/or organs. Autoimmune disorders may be the root of many diseases.

axon: The inner core of peripheral nerves.

BAER (brainstem auditory evoked response): Measures function of central nervous system, including pathway from brainstem.

basal ganglia: A series of structures located deep in the brain responsible for motor movements.

benign: Usually used in the context of referring to tumors that are not cancerous.

blepharospasm: Involuntary closure of the eyes and lids.

bradykinesia: Slowing of motor movements due to dysfunction of the basal ganglia and related structures.

CAT Scan (computerized axial tomography): A specialized X-ray examination that is often used to visualize the brain and spinal structures.

cataplexy: A symptom characterized by the sudden loss of postural tone, often resulting in the individual falling to the floor. Cataplexy is often part of the narcolepsy complex.

central nervous system: Refers to the brain and the spinal cord.

cerebral aneurysm: A defect that results in weakness in the wall of a blood vessel that can lead to bleeding in the brain.

cerebrospinal fluid: The fluid that surrounds the brain and the spinal cord.

cerebrovascular disease: Disorders that affect the blood vessels that supply the brain; may result in a stroke.

clonus: Brisk increase in tone with involuntary movements that result in dysfunction of the corticospinal tracts.

cluster headache: A syndrome that is more common in males resulting in one-sided, severe pain around the eye; usually occurs at night and is associated with nasal stuffiness and tearing of the eye.

coma: A state of unconsciousness in which patients lie unresponsive with the eyes closed.

corticospinal tract: The nervous system structures that begin in the brain and travel to the motor neuron cell to innervate the motor nerves.

deep tendon reflexes: Deep muscle stretch reflexes (such as the knee jerk) obtained by tapping on the tendons.

dementia: An acquired loss of cognitive function that may affect language, attention, memory, personality, and abstract reasoning.

demyelinating: An inflammatory process that disrupts the myelin coating of nervous system structures.

echocardiogram: A diagnostic test to detect abnormalities of the heart using an ultrasound probe to image the cardiac structures.

edema: Swelling; fluid is retained resulting in swollen tissues.

EEG (electroencephalography): Diagnostic test used to study brain wave activity; useful in the evaluation of seizure disorders.

EMG/NCV (electromyography/nerve conduction study): A test used to diagnose disorders in nerves and muscles in which a small needle is placed in the muscle (EMG) to study electrical conduction (NCV); results are seen on an oscilloscope screen and compared to normal values.

encephalitis: Inflammation or infection involving the brain.

evoked potentials: A series of electophysiologic tests that help to evaluate the function of specific elements of the nervous system involved in Multiple Sclerosis.

fasciculation: Twitching of the muscles seen in diseases involving the peripheral nervous system.

gadolinium: A contrast agent given intravenously during MRI (magnetic resonance imaging) to increase visualization of specific abnormalities.

hemiparesis: Weakness that affects one side of the body.

hemorrhage: Bleeding (such as in brain hemorrhage).

HIV (human immunodeficiency virus): Virus that affects the immune system and causes the disease known as AIDS (acquired immunodeficiency disorder).

ischemia: Lack of blood flow (such as in ischemic stroke).

lacunar: A subtype of stroke that affects the deeper parts of the brain and involves the tiny perforating arteries.

lumbar puncture (also known as a spinal tap): A procedure that involves removing some of the cerebrospinal fluid from the base of the spine; a physician uses a local anesthetic on the skin and soft tissues in the lower back before using a syringe to obtain cerebrospinal fluid from the spinal area.

lyme disease: A disease affecting the joints, nervous system, and heart that is transmitted by the deer tick; caused by a parasite known as Borrelia.

malignant: Usually refers to tumors that are cancerous; may refer to a disease state that has a debilitating unremitting course.

meningitis: Inflammation or infection of the meninges (the coverings of the brain).

metastatic: Usually used to describe cancerous lesions that spread to other organs in the body.

migraine: A headache syndrome characterized by throbbing, usually one-sided pain that may be associated with nausea, vomiting, and visual disturbances.

motor neuron cells: The cells located in the spinal cord that give rise to the nerves that supply the muscles.

MRI (magnetic resonance imaging): A technique that utilizes the properties of magnetic fields to provide images of the body (click here for additional information on MRI procedures).

multi-infarct dementia: A dementia that is caused by the cumulative affect of having had many strokes in the brain.

muscular dystrophy: A congenital (hereditary) disorder of the muscles resulting in weakness and muscle dysfunction.

myasthenia gravis: A disorder affecting the space between the nerve and the muscle (neuromuscular junction) that results in transient motor weakness of the face and limbs; due to an autoimmune process affecting the chemical Acetylcholine.

myelin: The outer, lipid-rich (fatty) layer that covers nerves and nervous system pathways in the brain and spinal cord.

myopathy: A disease resulting in muscle dysfunction that usually causes weakness and atrophy.

narcolepsy: A syndrome that is often hereditary; characterized by repeated attacks of sudden sleep that may be associated with other specific abnormalities making up the narcolepsy complex.

neurons: The nerve cells of the brain that carry out neurological function.

NPH (normal pressure hydrocephalus): Increase in pressure within the ventricles of the brain, causing dementia, gait difficulties, and urinary incontinence.

nystagmus: The jerking to and fro movement of the eyes that occurs when disorders affect the control of eye movement.

paraneoplastic: Disorders that occur due to the remote effects of cancer, such as through the mechanism of hormonal or antibody production.

paresthesias: Unusual sensory symptoms of tingling, numbness, or other abnormal feelings of sensation.

peripheral nervous system: Refers to the nerves and muscular structures.

photophobia (literally fear of light): used to describe condition when bright light is bothersome to individuals; often occurs in syndromes such as migraine headache.

plaque: The lesion that occurs in the white matter of the brain due to demyelination; also refers to the matter that builds up on the inner walls of arteries when substances that circulate in the blood (like fat and cholesterol) accumulate and potentially clog arteries.

prophylactic: Used to describe medications or treatments that are preventative in the treatment of disease.

ptosis: Drooping of the eyelids due to weakness of the muscles responsible for keeping the lids open.

radiculopathy: Irritation and inflammation of one of the nerve roots in the vicinity of the spinal column.

REM (rapid eye-movement sleep): The stage of sleep that is characterized by decreased muscle tone, rapid eye movements, and dreaming.

rigidity: Stiffness in the limbs or body due to dysfunction of the basal ganglia and related structures.

sciatic nerve: A large nerve in the lumbar-sacral spinal region that is composed of multiple nerve roots that supply the lower extremities.

seizure: The abnormal electrical discharge of brain cells (neurons) that results in a transient disturbance in brain function.

SEP (somatosensory Evoked Response): Measures function of central nervous system, including pathway from the extremities.

serotonin: An important neurotransmitter (communicates information chemically between brain cells) that is involved in pain disorders and emotional perceptions.

sleep apnea: A disorder that results in apnea (cessation of breathing) during sleep, often due to obstruction of the upper airway.

spasticity: Body stiffness involving the limbs that results from dysfunction of the corticospinal tracts.

spinal stenosis: A syndrome that results in narrowing of the dimensions of the spinal canal due to disc disease, bony changes, ligamentous thickening, and congenital factors.

status epilepticus: Seizures that continue for more than 20 minutes without an intervening period of responsiveness.

subarachnoid hemorrhage: Bleeding in the area surrounding the brain; usually a result of the rupturing of a cerebral aneurysm in the brain.

tensilon test: In this diagnostic test used to confirm Myasthenia Gravis disease, a substance that interferes with the breakdown of acetycholine is injected intravenously and the response is monitored.

TIA (transient ischemic attack): When neurological symptoms occur due to transient interruption of the blood flow to the brain.

torticollis: Involuntary turning of the neck to one side; can be seen in disorders of the basal ganglia.

toxoplasmosis: A parasitic disease that affects the brain; occurs in patients who are immunosuppressed (such as individuals with AIDS).

VER (visual evoked responses): Measures function of central nervous system, including the pathway from optic tract.

vertebrae: Bones that make up the spinal column.

vertigo: Dizziness or imbalance in an individual that often has a spinning or rotational component.

vestibular system: The parts of the nervous system that control equilibrium and balance.

white matter: The lipid-rich myelinated portion of the brain and spinal cord.