Glossary

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A | B | C | D | E | F | G | H | I | K | L | M | N | O | P | R | | T | V | W


A

Absence seizure
An absence seizure shows itself by momentary unconsciousness, possibly with twitching of the face, upward eye rolling and loss of grasp. Also known as petit mal seizures.

Acute attack
A sudden flare-up in symptoms.

Acquired brain injury (ABI)
Damage to the brain that occurs after birth and is not related to a congenital disorder or a degenerative disease. Damage may be caused by a traumatic injury to the head or by a non-traumatic cause such as a tumor, aneurysm, anoxia or infection.

Adjunctive therapy
"Add-on" therapy -- a medicine that's used with another type of medication.

Allergy
A hypersensitivity reaction to medicine or other substances, most commonly as a rash.

Antibiotic
A substance that destroys or inhibits the growth of microbes/microorganisms.

Antiepileptic drug (AED)
A medication used to control epileptic seizures.

Astatic seizure
Seizure that causes sudden loss of muscle tension, in which the person falls down and is often injured.

Aura
An aura is a signal or a "warning" that a seizure may be imminent, and can be the beginning of a seizure. Patients have described auras ranging from abnormal smells or tastes, to a funny feeling in the stomach, to sounds, colors, or irregular changes to emotions.

Auto-immune
The immune system recognizes and then gets rid of infections using cells called lymphocytes and proteins called antibodies. Usually the immune system can tell the difference between normal body proteins ("self") and those of bacteria or viruses ("foreign"). Occasionally "self" proteins are recognized as "foreign" and inflammation develops. This is called an autoimmune reaction.

Automatism
Things people do during a seizure in a state of diminished consciousness. (often pulling at their clothes)

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B

Biopsy
Removal of a small piece of living tissue from a part of the body for microscopic examination.

Brain stem
The lower portion of the brain. The brain stem is located just above the spinal cord and controls basic functions such as breathing and eye reflexes.

Basal ganglia
A group of structures and nuclei in the brain which help control movement.

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C

Central nervous system (CNS)
The central nervous system is made up of the brain and spinal cord. The central nervous system works together with the peripheral nervous system, which consists of all the nerves that carry signals between the CNS and the rest of the body.

Central fever
When the brain is unable to regularly control the body's temperature. This is a diagnosis of exclusion, meaning all other sources of infection have been ruled out.

Cerebellum
The part of the brain which controls balance and coordinates the muscles.

Cerebral cortex
The outer layer of the cerebrum. The cerebral cortex is what most people mean when they use the term "gray matter".

Chronic
Long-term or persisting.

Cerebellar ataxia
The cerebellum is part of the back of the brain. It particularly deals with the co-ordination of actions and balance. People who have disease of the cerebellum become clumsy, shaky (tremulous) in their limbs and develop slurred speech and poor balance. This is termed "cerebellar ataxia."

Cerebral
To do with the brain.

Cerebrospinal Fluid (CSF)
A clear fluid that surrounds the brain and spinal cord in the skull and spinal column. The body continually renews this fluid by producing and then absorbing it. Among other functions, it helps to support and cushion the brain and spinal cord. The analysis of CSF can be very helpful when diagnosing various neurological diseases including meningitis and encephalitis.

Cerebrum
Part of the brain thought to be involved in higher thought, learning, and personality. In humans, the cerebrum provides most of the mass and volume of the brain.

Clinical psychologist
A specialist who uses the science dealing with the brain and mental processes to assess and treat patients.

Clinical neurophysiologist
A doctor specializing in clinical neurophysiology.

Clonic seizures
Seizures with jerking movements.

Clonus
Repetitive, rhythmic contractions of a muscle when attempting to hold it in a stretched state. It is a strong, deep tendon reflex that occurs when the central nervous system fails to inhibit it.

Coma
Patients are said to be in a coma if they are unable to obey simple commands, do not utter comprehensible words and do not open their eyes even in response to pain.

Complex partial seizures
Similar to a simple partial seizure, but accompanied by impaired consciousness and recall. A person having a complex partial seizure will be unresponsive to questions or commands and will not be able to recall what happened during the seizure after it is over. Complex partial seizures used to be called temporal lobe or psychomotor seizures.

Cortical dysplasia
An abnormality in the development and organization of the cerebral cortex that can cause seizures and other neurologic disorders. These disorders can result from abnormal migration of nerve cells during development or can occur with infections such as encephalitis or disorders such as tuberous sclerosis or Sturge-Weber syndrome.

CT (computerized tomography) scan
X-ray examination that, with the help of computer technique, produces slice-shaped cross-sections of the organ being examined.

CT/MRI contrast
A dye injected into the veins to improve MRI and CT scan pictures.

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D

Dementia
Acquired reduction of mental abilities.

Diagnostic treatment
Trial treatment with antiepileptic medicine of a person when it has not been possible to ascertain whether the person has epilepsy.

Differential diagnosis
The term used by doctors to refer to the various possible causes of a patient's symptoms.

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E

EEG (Electroencephalography)
The EEG (electroencephalogram) is a recording of the natural electrical activity of the brain. It involves placing small recording electrodes on the scalp and is completely painless and harmless. The analysis of the EEG can be very helpful in diagnosing various neurological diseases including epilepsy.

Encephalitis
Inflammation of the brain.

Encephalopathy
Any disease or disorder affecting the brain.

Epilepsy
A disorder characterized by two or more seizures that are not caused by clear precipitating factors such as alcohol withdrawal or hypoglycemia.

Epileptic focus
Area in the brain that triggers epileptic activity.

Epileptic fit (seizure)
A sudden and short-lived electrical disturbance in the brain which often, but not always, causes abnormal shaking movements and a brief loss of consciousness.

Epileptic syndrome
Age-linked type of epilepsy in which a group of different symptoms make up the picture of the illness.

Extubation
To remove a patient from a breathing-assisted device.

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F

Fatigue
Incapacitating mental or physical tiredness that can lower one's seizure threshold.

Frontal lobe
A region of the cerebrum. The frontal lobe is responsible for a variety of complex behaviors including emotions, initiative, judgment, personality, and -- for most right-handed people -- the ability to speak.

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G

Generalized convulsion or seizure
This type of seizure, which arises over a wide area of the brain, causes loss of consciousness and affects the whole body. These are sometimes referred to as grand mal seizures.

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H

Half-life
The time it takes for the concentration of a drug to fall to half of the peak concentration. Of importance in finding out how many doses should be taken in a day.

Hemiparesis
This is muscular weakness or partial paralysis on one side of the body.

Hemiplegia
This is a paralysis or weakness on one side of the body caused by damage to the motor nerve tracts in the opposite side of the brain.

Hydrocephalus
An abnormal increase in the amount of cerebro-spinal fluid within the cavities of the brain.

Hyperventilate
Breathe in and out quickly. (Used as a method of provocation during EEG. Particularly suited to provoke absences)

Hypsarrhythmia
Special changes in EEG in infantile spasms.

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I

Ictal
That which happens during a seizure.

Idiopathic epilepsy
Hereditary factors combined with biochemical changes in the brain are supposedly involved.

Inflammation
A process in which part of the body can become hot and swollen, not necessarily directly due to an infection.

Interaction
One drug's influence on the breakdown of another drug.

Interictal
That which happens between seizures.

Intubate
To put a patient on a ventilator to assist with their breathing.

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K

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.

Kindling
The phenomenon by which epilepsy can be induced in animals. It is done by stimulating the brain electrically. One stimulation is not enough to induce a seizure, but when repeated often enough, the animal begins to have seizures without being stimulated.

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L

Level of consciousness
The level of consciousness of a person can vary between being fully conscious and being in a deep coma, and there are many levels between these two extremes. Medical staff will assess a person’s level of consciousness by checking for certain responses, which include eye opening, verbal response and response to stimulation.

Lobes
Regions of the cerebrum.

Lumbar
The name given to the lowest mobile portion of the spine, sometimes referred to as the small of the back.

Lumbar puncture
A medical test, involving taking a small sample of fluid from the lower spine using a needle, a bit like a blood test. This is usually done with some local anaesthetic when the person is lying on their side on a bed or couch.There are no serious side effects, although some people may get a headache afterwards.

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M

Meninges
The three connective tissue membranes that line the skull and vertebral canal and enclose the brain and spinal cord.

Meningitis
An inflammation of the membranes covering the brain (the meninges) due to infection.

Monotherapy
Using only one medication to treat a condition.

MRI (magnetic resonance imaging) scanning
Magnetic Resonance Imaging is a technique that gives very clear pictures of an area of the body (e.g. the brain) in any plane. The pictures obtained are of very high quality and use magnetism rather than x-rays. The scan process is painless but somewhat claustrophobic, and can be noisy.

MRI/CT contrast
A dye injected into the veins to improve MRI and CT scan pictures.

Myclonic jerk
Sudden jerk of the arm or leg. Can occur as a particular seizure type in epilepsy. Most people experience something similar at some time when falling asleep, but in these cases it is not epilepsy.

Myelin
The fatty protein coat around nerve fibres. Myelin sheaths increase the speed at which electrical impulses or messages travel.

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N

Nerve cell
The basic functional unit of the nervous system. These specialised cells transmit chemicals and electrical impulses and so carry information from one part of the body to another.

Nerve fiber
A long thread that extends from a nerve cell and carries nerve impulses. Bundles of nerve fibres running together form a nerve.

Neurological
Refers to conditions occurring in the nervous system, including the brain, spine and all the peripheral nerves.

Neurologist
A medical doctor who is specially trained to diagnose disorders of the brain, spinal cord and nerves, and to treat them with medical interventions if appropriate.

Neuron
Another term for a nerve cell. They are the key cells in the central nervous system that produce and carry the electrical impulses or messages that translate our thoughts into actions. Their long projections or extensions are called axons.

Neuro-transmitter
A chemical messenger used by the nerve cells.

Nervous system
The vast network of nerve cells which carries information to and from all parts of the body in order to bring about bodily activity. It is classically divided into the brain, spine and peripheral nervous system.

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O

Occupational therapy
Occupational therapists help people regain their independence and adapt to any disability. They can recommend special tools to help people perform everyday tasks more easily and can also recommend adaptations to the house, such as hand rails, bath seats and stair lifts.

Optic neuritis
Inflammation in the nerve which joins the eye to the brain (the optic nerve).

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P

Parietal lobe
A region of the cerebrum involved in the reception of tactile sensations. The parietal lobe contains the sensory strip which interprets sensations such as touch or pressure on the face, hand, arm or body.

Partial seizures
A seizure which occurs only in a specific part of brain. Partial seizures often start with an aura and most arise in the frontal or temporal lobe. The symptoms of a partial seizure depend on area of the brain involved in the seizure.

Pediatrician
A doctor who specializes in children’s medicine.

Photosensitive epilepsy
Form of epilepsy in which seizures can be caused by blinking light.

Physiotherapy
Maximizing movement ability and controlling pain in the joints, muscles and bones.

Polytherapy
Treatment with more than one antiepileptic medicine.

Post-ictal phase
The period of time immediately following a seizure. Someone in the postictal phase may go through a period of confusion or may sleep for hours until rested.

Prodromes
Longer pre-warning of a seizure, often lasting several days. Most commonly depression.

Psychiatry
A branch of medicine concerned with mental illnesses.

Positron Emission Tomography scan (PET scan)
This is a scan that provides three-dimensional pictures that can show the chemical activity of the tissues being examined.

Psychologist
Someone involved in the scientific study of the mind and mental processes.

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R

Rehabilitation
This refers to the overall process of ensuring that people make the best possible recovery from their stroke. It usually involves help from a range of health and social care professionals.

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S

Scan
The examination of the body or part of the body using CT or MRI.

Secondary generalization
Partial seizure that develops into a generalized seizure.

Simple partial seizures
During a simple partial seizure, the person will be alert and able to respond to questions or commands. People who have had a simple partial seizure can remember what occurred during the seizure.

SPECT (single photon emission computerized tomography) scanning
Investigation of the brain's blood flow.

Speech therapist
A specialist in helping people with speech, language, communication and swallowing difficulties.

Spike
Particular wave pattern in EEG. Typical of epilepsy.

Spinal cord
An enlarged collection of nerve fibers and nerve cell bodies that leaves the skull and travels through the vertebrae of the spine.

Spinal fluid
Fluid that surrounds the brain and the spinal cord.

Status epilepticus
Refers to a seizure that lasts longer than 30 minutes or a series of seizures with no recovery of consciousness or behavioral functions between attacks. Partial seizures can progress to status epilepticus.

Stress convulsions
Generalized seizures triggered off by a stressful situation.

Symptomatic
A patient is symptomatic if he or she experiences symptoms. A condition becomes symptomatic when it starts to produce symptoms, even though the condition itself may have been present for some time beforehand.

Symptoms
The sensations or feelings reported by patients which tell them that something is wrong.

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T

Temporal lobe
The region of the cerebrum responsible for speech (ie. the ability to understand language), consciousness, hearing, smell, and taste.

Therapeutic range
The concentration of medicine in the blood that is most effective with the fewest side effects. Applies to an average person and not necessarily to the person in question. Depends on the severity of the epilepsy.

Todds paralysis
Paralysis after a seizure

Tolerance development
Reduced effect of medicine with time.

Tonic convulsions
Convulsions with muscular rigidity.

Tonic seizure
Seizure in which the person only has tonic convulsions.

Tonus
Muscular tension.

Tracheostomy
The creation of an opening in the trachea (windpipe) through the neck for the insertion of a tube to assist breathing.

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V

Ventilator
A machine designed to move air in and out of a person's lungs to assist breathing mechanically (a life support machine).

Video EEG
Long-term EEG in which a video recording of the person is combined with an EEG recording.

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W

Wada test
Investigation to find out in which half of the brain the speech center is located.

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