Common Terms
Understanding epilepsy begins with understanding the language surrounding it. This glossary was created to help families, caregivers, and advocates feel more confident when navigating medical conversations, research, and everyday life with seizures.
A
Absence Seizure
A brief seizure that causes a person to stare blankly or lose awareness for a few seconds. Often mistaken for daydreaming.
Anti-Seizure Medication (ASM)
Medications used to control or reduce seizures. Sometimes called anticonvulsants or anti-epileptic drugs (AEDs).
Aura
A sensation or feeling that may happen before a seizure. It can include smells, visual changes, anxiety, or unusual body sensations.
B
Breakthrough Seizure
A seizure that occurs even while someone is taking medication and following treatment.
C
Clonic Movement
Repeated rhythmic jerking of muscles during a seizure.
Convulsion
Uncontrolled shaking or muscle contractions caused by abnormal brain activity.
D
Developmental Delay
When a child reaches speech, learning, or motor milestones later than expected for their age.
E
EEG (Electroencephalogram)
A test that records electrical activity in the brain to help diagnose epilepsy.
Epilepsy
A neurological condition defined by recurring, unprovoked seizures.
Epileptologist
A neurologist who specializes specifically in epilepsy and seizure disorders.
F
Febrile Seizure
A seizure triggered by a fever, most common in young children.
Focal Seizure
A seizure that starts in one area of the brain. Awareness may or may not be affected.
G
Generalized Seizure
A seizure involving both sides of the brain at the same time.
Grand Mal (Tonic-Clonic) Seizure
A seizure that includes loss of consciousness, stiffening of the body, and strong jerking movements.
H
Hypoxia
A lack of oxygen to the brain or body, which can be a concern during severe seizures.
I
Ictal Phase
The active stage of a seizure when symptoms are happening.
M
Myoclonic Seizure
Sudden, brief muscle jerks that may look like a quick twitch or startle.
N
Neurologist
A doctor who treats conditions related to the brain and nervous system.
P
Periventricular Leukomalacia (PVL)
A type of brain injury often linked to premature birth or low birth weight that may cause developmental delays or neurological challenges.
Postictal State
The recovery period after a seizure when a person may feel confused, tired, emotional, or need rest.
Photosensitivity
When flashing lights or visual patterns trigger seizures in some individuals.
S
Seizure
A sudden burst of abnormal electrical activity in the brain that can affect movement, awareness, or behavior.
Seizure Action Plan
A written plan that explains how to respond safely before, during, and after a seizure.
Seizure Threshold
The level at which the brain is more or less likely to have a seizure.
Status Epilepticus
A medical emergency where a seizure lasts longer than five minutes or seizures occur back-to-back without recovery.
SUDEP (Sudden Unexpected Death in Epilepsy)
A rare but serious risk where a person with epilepsy dies unexpectedly without a known cause.
T
Tonic Phase
The part of a seizure where muscles stiffen.
Trigger
Anything that may increase seizure risk, such as illness, lack of sleep, stress, missed medication, or flashing lights.
V
Vagus Nerve Stimulation (VNS)
A device implanted in the body that sends electrical signals to help reduce seizures.