Glossary

Absence Seizures

A type of generalized seizure. These seizures typically cause a very brief lapse of awareness/ consciousness, so brief that they may go unnoticed, and are characterized by staring with arrest of movement. Often picked up by teachers as classroom day-dreaming.

Anti-Seizure Medication (ASM)

Medication prescribed to minimize the frequency and severity of experience by the person living with epilepsy. 

Atonic Seizure 

A type of generalized seizure where there is a sudden loss of muscle tone. The person may fall to the ground like a wet towel. 

Aura

A type of focal seizure where the person can feel and remember the experience. It is a sensory event which only the patient can describe and cannot be seen. Per se an aura is a simple partial seizure.

Automatism

A repetitive, automatic random movement occurring during or after seizures like fiddling with clothes, or repeated swallowing, chewing, lip smacking, verbalization and others. 

Co-Diagnosis or Comorbidity

When a person is diagnosed with more than one condition that has co-contributing impacts on the person.

Cognitive

Related to the thinking processes, and includes memory, problem solving, attention, concentration etc.

Cognitive Disability 

A term used when a person has certain limitations in mental functioning and in skills such as communicating, taking care of him or herself, and social skills.

Drug Resistant Epilepsy

Epilepsy uncontrolled with anti-seizure medications. 

Dyscognitive

A state where awareness of the surrounding environment is not maintained throughout an episode.

EEG With Prolonged Video Monitoring

An EEG performed over an extended period of time while a person is being monitored by a video camera. If an event occurs and is recorded, the doctor can then simultaneously view both the video recording and the EEG recording.

Electroencephalogram (EEG)

An EEG records small electrical signals from the brain onto a computer. Small discs, called electrodes, are placed on a person’s scalp using a non-irritant special paste. The electrodes pick up electrical signals and brain waves and pass them along wires to the EEG machine. The electrodes only pick up electrical activity and don’t give out electricity.

External Stimuli

Used for assessing the consciousness level of a person when not obvious (e.g. voice commands or gentle physical stimuli).

Focal Seizure

These seizures occur when the seizure activity occurs in only one part of the brain.

Functional/Psychogenic Seizure

Formerly called psychogenic seizure, clinically to the uninitiated may look like an epileptic seizure, but are very bizarre, not stereotyped, a person does not experience any major injury or tongue bite, usually occurs in front of an audience and the duration may be in hours. Video EEG monitoring is of great assistance in identifying seizures of this kind. The EEG during this episode remains normal.

Generalized Seizure

A seizure that affects the whole brain. Common generalized seizures include tonic-clonic seizures and absence seizures.

Ictal

The period of time during a seizure. This differs from interictal which is the time between two seizures, and postictal being the time immediately after a seizure.

Idiopathic

Describes a disease or disorder that has no known cause.

Infantile Spasms

Also called Salam seizures, it is characterized by brief, sudden flexion of the head, trunk and limbs. Occurs in infancy and early childhood. 

Ketogenic Diet

A specialized diet sometimes used to control difficult-to-control seizures. The Modified Atkins Diet (MAD), a modified type of ketogenic diet is also sometimes used. 

Magnetic Resonance Imaging (MRI) Scan

An MRI scan looks at a person’s brain structure. An MRI uses magnetic fields and radio-waves which provide more detail than a CT scan. It produces very clear images of the brain without using x-rays.

Myoclonic Seizure

Involves a brief, sudden jerk (usually symmetric) of the muscles in the upper limbs and body. It is the only generalized type of epilepsy in which no loss of awareness or consciousness occurs.

Nervous System

The network of nerve cells and nerve fibers that conveys sensations to the brain and motor impulses to organs and muscles.

Neurodevelopmental

Growth and development of the brain or central nervous system.

Positron Emission Tomography (PET) Scan

A PET scan is a nuclear imaging test which shows the metabolic activities (energy usage) of a person’s brain. The person is injected with a safe, short-lived radioactive substance into the bloodstream. Once it has been absorbed, a CT scan is performed soon afterwards.

Prodromal

A forewarning symptom indicating the onset of a disease, often before more diagnostically specific signs and symptoms develop.

Puberty

The period during which adolescents reach sexual maturity and are capable of reproduction.

Reflex Epilepsy

When seizures are triggered by sensory stimuli like touch, sudden loud noise etc.

Seizure

A temporary sudden change in the electrical activity in the brain which causes a change in behaviour, thoughts, sensation, and movements.

Seizure Clusters

Continuous seizures occurring one after the other over a short period of time. There is a recovery period between each seizure, however the pattern and timing does not follow normal seizure activity.

Single-Photon Emission Computed Tomography (SPECT) Scan

A SPECT scan is a nuclear radiology study that measures blood flow in the brain. A safe, short-lived radioactive substance is injected into the arm of a person while they are having a seizure and a CT scan is performed soon afterwards. A SPECT scan is only conducted during admission to an Epilepsy Monitoring Unit in a hospital, and is performed by specially trained healthcare staff, such as nurses.

Status Epilepticus

When a seizure is prolonged or where seizures occur in close succession with the person not recovering between seizures the condition is called status epilepticus. It can occur with any type of seizure and can be convulsive or non-convulsive.

Syndrome

Refers to a group of symptoms and features which usually occur together and can suggest a particular condition.

Temporal Lobe Epilepsy

Term for epilepsy arising in the temporal lobe of the brain.

Tonic Seizure

A generalized seizure in which the person falls to the ground like a log of wood. The whole body is stiffened without jerking

Tonic Clonic Seizure

A generalized seizure in which the person falls, loses consciousness, stiffens and the body jerks.

Trigger

Situation or event that can bring on a seizure.

Verbal Memory

This refers to the memory of words and other concepts involving language.

Visual Memory

This refers to the ability to recall visual information that has been seen (e.g. objects, places, animals or people). This refers to the thought processes that involves visual and spatial awareness.