Different types of epileptic seizure
For those of us who haven’t had any experience with the condition, when we hear the word ‘epilepsy’ it conjures a certain stereotype: a person who is sensitive to flashing lights and suffers one type of seizure.
Actually, there are many different types of seizures that people with epilepsy experience. They can be triggered by all sorts of stimuli, or none at all, and each presents differently.
Focal onset seizures affect one part (or the ‘focus’) of the brain.
Focal onset seizures fall into two categories:
- Focal aware seizures (FAS) - during focal awareness seizures, the person retains awareness, aka is awake, alert and will remember the seizure after it has happened.
- Focal impaired awareness seizures (FIAS) - FIAS affect more of the brain than FAS, and the person affected may lose consciousness, appear confused, and be unable to respond. Following the seizure, the person may still feel confused or tired, and may not remember the seizure.
Generalised onset seizures
These seizures come on very quickly and affect both sides of the brain. The person will be unconscious (except in the case of myoclonic seizures)
- Tonic-clonic seizures - these are the seizures people typically think of when they think of epilepsy. During these seizures, the person becomes unconscious, their body stiffens and jerks/shakes rhythmically.
- Clonic seizures - these seizures present as rhythmic jerking/shaking of one or both sides of the body.
- Tonic seizure - during a tonic seizure, a person may become suddenly stiff. This can lead them to fall over if standing. They are usually brief and come on without warning.
- Atonic seizures - during atonic seizures, a person's muscles relax suddenly, and they go floppy and fall. They are usually brief and come on without warning.
- Myoclonic seizures - during myoclonic seizures, the person’s muscles will jerk suddenly, as if they have been electrocuted.
- Absence seizures - during an absence seizure, the person will appear disconnected from others around them. They may stare blankly into space, or their eyes can roll into the back of their head.
The symptoms of seizures vary from person to person and depending on how much of the brain is affected. Symptoms can be both motor and non-motor. During motor seizures, people will move, e.g. walk around, tug at clothes, rub their hands. Non-motor seizures cause changes in how the person is feeling. They may feel a strange ‘wave’ come over them, have intense emotions, a racing heart, hot/cold flushes.
If you are with someone who is experiencing a seizure, Epilepsy Action recommends making sure to first move them out of harm's way. Give them lots of room, and cushion their head if needed. Speak quietly, and in a reassuring manner - some people can hear when they’re having a seizure. Remember that behaviours exhibited during a seizure can seem alarming, but do not worry.
If you’d like to learn more about epilepsy, we can recommend these fantastic resources: