Absence seizures (petit mal): This type of seizure
typically occurs in childhood and is distinguishable by
short periods ( 5-15 seconds) of staring, blinking, rolling
of the eyes, or arm movements. These brief lapses of consciousness
are followed by a return to full awareness.
drugs (AEDs): A category of drugs that can help
control the frequency and severity of seizures; they
also are known as anticonvulsants. There are several
AEDs available; each works in different ways and has
proven effective for certain types of epilepsy.
Aura: An unusual physical sensation that occurs
in some people before a seizure occurs. Auras, which
vary depending on the individual, can be a strange taste
or odor, a tense feeling, or even a sound.
Breakthrough seizures: Seizures that periodically
occur in a person whose epilepsy is otherwise well controlled.
Brain stem: Located at the front of the cerebellum,
it links the cerebrum to the spinal cord and controls
various automatic as well as motor functions. It is
composed of the medulla oblongata, the pons, the midbrain,
and the reticular formation.
Cerebellum: Located at the back of the brain,
the cerebellum controls body movement, i.e., balance,
Cerebrum: The brain's largest section can be
divided into two parts: the left and right cerebral
hemispheres. These hemispheres are joined by the corpus
callosum, which enables "messages" to be delivered
between the two halves. The right side of the brain
controls the left side of the body, and vice versa.
Each hemisphere also has four lobes that are responsible
for different functions: frontal (behavior, emotions,
problem solving); temporal (short-term memory, identification
of sound and smell); parietal (touch, language comprehension),
and occipital (visual processing, shape and color identification).
Complex partial seizures (psychomotor or temporal
lobe epilepsy): This type of seizure affects consciousness
and originates from the temporal lobes of the brain.
Complex partial seizures are characterized by automatisms,
which are involuntary, repetitive behaviors such as
head turning and random movement that is not remembered
by the person after the seizure is over.
Continuous Video EEG Monitoring: When a longer
EEG study is required, patients stay in a special unit
in the hospital for at least 24 hours. In the unit,
a video camera connected to the EEG provides constant
monitoring, enabling the medical team to pinpoint the
area where a seizure occurs and track the patient's
physiological response to the seizure.
Cranial nerves: Twelve pairs of nerves responsible
for various functions, including speech, hearing, taste,
facial sensation and facial expression, balance, and
Cranium: The bony covering that surrounds the
brain. The cranium and the facial bones comprise the
Electroencephalogram (EEG): During this non-invasive
test, several electrodes are placed on a patient's scalp.
They record electrical impulses from the brain known
as brain waves.
"Eloquent" brain: Areas within the
brain that control the senses, motor functions, and
Functional Image Guided Surgery(FIGS):A combination
of Functional MRI with frameless stereotactic surgery
that creates a precise, detailed "road map"
for the surgeon to follow during an operation
Frontal lobe: One of the brain's four lobes,
the frontal lobe is where such functions as speech,
emotions, and reasoning originate. As the name suggests,
it is located at the front of the brain.
Functional MRI: With Functional MRI, a map of
the brain can be created that indicates where language,
motor, and sensory areas are located. An imaging technique
that incorporates "real time" sequence, it
is also faster than traditional magnetic resonance imaging.
Generalized seizures: Seizures that originate
in several parts of the brain.
Hypothalamus: The part of the brain that acts
as a messenger to the pituitary gland; it also plays
an integral role in body temperature, sleep, appetite,
and sexual behavior.
Intractable epilepsy: A form of epilepsy that
does not improve (fewer or less severe seizures) with
medication. Surgery may be the next recommended course
of treatment to improve the patient's condition.
Ketogenic diet: This special high-fat,
low carbohydrate diet is sometimes recommended for children
with intractable epilepsy. It is carefully designed
to help the patient's body make large amounts of ketones,
which are produced when fats are processed in the liver.
The diet helps reduce the number of seizures in some
patients, although precisely why this beneficial effect
occurs is not known.
Left hemisphere: The half of the cerebrum
sometimes referred to as the "dominant" hemisphere.
It has primary responsibility for speech and language.
However, in some left-handed people, the right hemisphere
controls speech function.
Medulla oblongata: This section of the brain
stem connects the brain to the spinal cord. It is responsible
for involuntary functions such as breathing, heart rhythms,
Meninges: Protective layers of
tissue that surround the brain and the spinal cord.
Midbrain: Part of the brain stem, it is the
origin of the third and fourth cranial nerves, which
control eye movement and eyelid opening.
Neuropsychological testing: A patient's cognitive
abilities, memory, and motor skills are assessed through
a variety of tests.
Occipital lobe: This lobe is located at the
back of the brain and controls many visual functions.
Optic chiasm: The area in the front of the brain
where the optic nerves cross.
Parietal lobe: This lobe is associated with
perception of stimuli such as pain and touch.
Partial seizures: Seizures that begin in one
part of the brain.
Pons: This part of the brain stem is the origin
of four pairs of cranial nerves: fifth (facial sensation);
sixth (eye movement); seventh (taste, facial expression,
eyelid closure); and eighth (hearing and balance).
Posterior fossa: The part of the skull containing
the brain stem and the cerebellum.
Right hemisphere: The half of the cerebrum
that processes visual information.
Seizure focus: The area(s) of the brain where
Simple partial seizures: These seizures generally
do not affect consciousness and are the most common
type of epilepsy. They may cause sudden, jerking motions
of the body and affect vision or hearing.
Single Photon Emission Computed Tomography (SPECT):
A scanner that measures a low-dose radioactive material
as it circulates through the brain. SPECT can track
cerebral blood flow and detect alternations in brain
metabolism between and during seizures.
Status epilepticus: Repeated convulsions that
occur without a break of consciousness between them.
This is a medical emergency that can result in permanent
Temporal lobe: This lobe is associated with
memory, hearing, and perception.
Thalamus: A small area in the brain that relays
information to and from the cortex and translates impulses
related to pain, attention, and alertness.
Tonic-clonic seizures (grand mal): These seizures
are characterized by a stiffening of the body and jerking
body movements. A person sometimes loses consciousness
during a tonic clonic seizure and may also have shallow
breathing and a loss of bowel/bladder control.
Triggers: In some people, certain factors
that seem to bring on or "trigger" a seizure.
Among the most common triggers are: lack of sleep; flashing
lights; alcohol; smoking; the hormonal changes brought
on by the menstrual cycle; and stress
Vagal Nerve Stimulator:
A small, battery-operated device that sends low levels
of electrical current to the left vagal nerve. This
nerve sends messages to the area of the brain believed
to be responsible for producing seizures. The vagal
nerve stimulator is implanted in the patient's body,
much like a pacemaker.
Ventricles: Four small cavities within the brain,
they contain the choroid plexus, which produce cerebrospinal