A seizure is a sudden burst of uncontrolled electrical activity in the brain that can include sensory, motor, and psychic manifestations. It can cause changes in behavior, movement, and levels of consciousness. Seizures may include convulsions, which are sudden, irregular, and rapid movements of the limbs or body due to involuntary muscle contraction. There are two main types of seizures:

  1. Provoked seizures are those that have an identifiable cause. Some common causes of provoked seizures are illnesses that affect the brain such as metabolic derangements, infections, tumors, and vascular lesions. Drugs and brain injury can cause seizures as well.
  2. Unprovoked seizures have no identifiable cause. Epilepsy is a condition of recurrent unprovoked seizures. There are two categories of epileptic seizures: focal seizures and generalized seizures. We will discuss these categories in detail now.

Focal Seizures

Focal seizures are epileptic seizures that begin in a specific or focal area of one cerebral hemisphere. There are two types of focal seizures: those that occur without impairment of consciousness or awareness, and those that occur with impairment.

Generalized vs Focal Seizures Image by Becky Torgerson BYU-Idaho F19

Generalized Seizures

Generalized seizures are epileptic seizures that involve both hemispheres of the brain. They can be preceded by focal seizures. There are various types classified based off of symptoms:

There are a variety of medications available to treat seizures. It is important to diagnose the type of seizure before beginning treatment because not all types of seizures respond to medication in the same way.

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