Focal aware seizures
(previously called simple partial seizures)
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.
Some people find their focal aware seizures hard to put into words. During the seizure they may feel ‘strange’ but not able to describe the feeling afterwards. This may be upsetting or frustrating for them.
FAS are sometimes called ‘warnings’ or ‘auras’ because, for some people, a FAS develops into another type of seizure. The FAS is then a warning that another seizure will happen (see focal to bilateral tonic-clonic seizures).
Some focal seizures involve movements, called motor symptoms, and some involve unusual feelings or sensations called non-motor symptoms.
Motor symptoms can include:
- making lip-smacking or chewing movements, repeatedly picking up objects or pulling at clothes;
- suddenly losing muscle tone and limbs going limp or floppy, or limbs suddenly becoming stiff;
- repetitive jerking movements that affect one or both sides of the body;
- making a loud cry or scream; or
- making strange postures or repetitive movements such as cycling or kicking.
Non-motor symptoms can include:
- a ‘rising’ feeling in the stomach;
- deja vu (feeling like you've 'been here before');
- getting an unusual smell or taste;
- a sudden intense feeling of fear or joy;
- a strange feeling like a ‘wave’ going through the head;
- stiffness or twitching in part of the body (such as an arm or hand;
- a feeling of numbness or tingling;
- a sensation that an arm or leg feels bigger or smaller than it actually is; or
- visual disturbances such as coloured or flashing lights; or
- hallucinations (seeing something that isn’t actually there).
Information produced: November 2023
Focal impaired awareness seizures (FIAS) affect a bigger part of one hemisphere (side) of the brain than focal aware seizures. This seizure was previously called complex partial seizures.
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.
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 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.