Epileptic seizures or fits are caused by abnormal electrical activity in the brain. Electrical impulses act on several areas of the brain affecting muscular function, sensation and awareness. The muscles may undergo sudden violent contractions and there may even be a brief loss of consciousness.
Some of the symptoms of epileptic seizures are described below:
The most common form of generalized seizure seen in epilepsy is the grand mal seizure, which begins with a stiffening of the skeletal muscles that causes the body to contract and a person to fall down. This phase of the seizure is called the tonic phase and usually lasts for around 20 seconds. This phase is followed by several minutes of rhythmic contractions across the body in what is know of as the clonic phase. These grand mal seizures are also called tonic-clonic seizures.
People with epilepsy often experience warning signs that they may be about to experience a fit and these are referred to as auras. Some examples of auras include a sense of fear or anxiety, a feeling of déjà vu, altered vision, confusion and a strange sense of smell or taste. Another example of an aura is an odd sensation of movement similar to that felt in vertigo and is referred to as a vertiginous epilepsy. Auras can provide a warning signal that a generalized seizure is about to occur.
Some seizures may cause only numbness in one area of the body, while some can cause a complete loss of muscle tone in the body that can lead to a person falling and injuring themselves.
When abnormal electrical activity only occurs in part of the brain, this is referred to as a partial seizure. Two forms of partial seizure exist: simple partial seizure where there is no loss of consciousness, and complex partial seizure, where there is a full loss of consciousness and a person cannot remember what has happened once the seizure has passed. Partial seizures can progress to generalized seizures.
If the seizure does not pass, it is termed status epilepticus, a life threatening condition where the brain remains in a persistent state of seizure that is less likely to stop the longer it lasts.
When the brain recovers from a seizure, a person may feel confused and short-term memory may be affected.
In one form of epileptic seizure called absence seizure, a person appears blank or non responsive, but awake. These seizures usually last for less than 20 seconds and are also termed petit mal seizures.
Further Reading
Multiscale modeling and personalized therapies: tackling the complexities of epilepsy with degeneracy concept