Focal impaired awareness seizures (previously called complex partial seizures)
Focal impaired awareness seizures (FIAS) affect a bigger part of one hemisphere (side) of the brain than focal aware seizures.
The person’s consciousness is affected and they may be confused. They might be able to hear you, but not fully understand what you say or be able to respond to you. They may not react as they would normally. If you speak loudly to them, they may think you are being aggressive and so they may react aggressively towards you.
FIAS often happen in the temporal lobes but can happen in other parts of the brain.
After the seizure, the person may be confused for a while. This is sometimes called 'post-ictal' (after seizure) confusion. It may be hard to tell when the seizure has ended. The person might be tired, and want to rest. They may not remember the seizure afterwards.
Information produced: November 2023
In focal aware seizures (FAS), previously called simple partial seizures, the person is conscious (aware and alert) and will usually know that something is happening and will remember the seizure afterwards.
Myoclonic means ‘muscle jerk’. Muscle jerks are not always due to epilepsy (for example, some people have them as they fall asleep). Myoclonic seizures are brief but can happen in clusters (many happening close together in time) and often happen shortly after waking.
In an atonic seizure (or 'drop attack') the person’s muscles suddenly relax and they become floppy. If they are standing they often fall, usually forwards, and may injure the front of their head or face. Like tonic seizures, atonic seizures tend to be brief and happen without warning. With both tonic and atonic seizures people usually recover quickly, apart from possible injuries.
These are the seizures that most people think of as epilepsy. the person becomes unconscious their body goes stiff and if they are standing up they usually fall backwards. they jerk and shake as their muscles relax and tighten rhythmically.
Absence seizures are more common in children than adults and can happen very frequently. During an absence a person becomes unconscious for a short time. They may look blank and stare, or their eyelids might flutter. They will not respond to what is happening around them. If they are walking they may carry on walking but will not be aware of what they are doing.
In March 2017 the International League Against Epilepsy (ILAE), a group of the world's leading epilepsy professionals, introduced a new method to group seizures. This gives doctors a more accurate way to describe a person's seizures, and helps them to prescribe the most appropriate treatments.