Absence seizures may be fleeting and so can be missed. They can be typical, which are the most common, or atypical. A person having a typical absence seizure suddenly stops everything they are doing: they may look like they are staring into space or have a blank look on their face. Their eyes may turn upwards and their eyelids flutter.

Typically absence seizures last from a couple of seconds to almost half a minute and a person may be confused for a brief time. Atypical absence seizures can last longer than the typical type but there is significant overlap; they have a slower onset and a person may exhibit different symptoms, including lip smacking or chewing movements, rubbing their fingers together or other hand movements.^3,6 

During an atonic seizure some or all of a person’s body may become limp. For example, their eyelids may droop, their head may drop or nod forward or they might drop things. If a person is standing when they have an atonic seizure they will fall down so head protection may be needed by some people with these types of seizures.

Usually these seizures start in both sides of the brain – known as generalised atonic seizures. If they start in one part of the brain they are called focal atonic seizures.^3,6  

Clonic seizures are characterised by jerking movements that are more regular and sustained than during a myoclonic seizure. They may last from a few seconds to a minute. That contrasts with the clonic movement see after the muscles stiffen in a tonic-clonic seizure, which can last for seconds up to one to two minutes.

Focal clonic seizures begin in the motor region of one side of the brain and the jerking movements affect one side of the body only. When clonic seizures affect both hemispheres of the brain at the same time the clonic movements affect both sides of the body or the whole body at the same time and are termed generalised clonic seizures.⁶ 

During myoclonic seizures people experience short shock-like jerks or twitches of their muscles. They usually last for a few seconds and may happen in isolation or there can be several in a short time. There are a number of different types of epilepsy syndrome (describing specific signs and symptoms) that involve myoclonic seizures, including:^1,6

– Juvenile myoclonic epilepsy where seizures usually affect the neck, shoulders and upper arms, most often soon after waking up. Usually starts around puberty or sometimes early adulthood.

– Lennox-Gestaut syndrome is a rare form of epilepsy that includes other types of seizure as well. Usually begins in early childhood.

– Progressive myoclonic epilepsies are rare and involve tonic-clonic seizures as well as myoclonic seizures.

– Dravet syndrome, a rare, genetic epileptic encephalopathy in which seizures do not respond well to antiseizure medication.

During an epileptic spasm arms, legs or neck can flex or extend in brief (1–3 second) spasms. Typically there are clusters of such movements that happen every 5–10 seconds over a period of 5–10 minutes. The spasms are often seen shortly after waking and can happen several times during the day. Infants with these seizures often become irritable and cry, which sometimes leads to a diagnosis of colic.⁶