Seizures

A seizure is a sudden, uncontrolled burst of electrical activity in the brain that can cause temporary changes in movement, behavior, sensations, or states of awareness. It’s important to understand that not all seizures look the same, and not everyone who has a seizure has epilepsy.

Here’s a breakdown of key aspects of seizures:

What happens during a seizure? Normally, nerve cells (neurons) in the brain communicate by sending electrical signals. During a seizure, many neurons fire all at once, disrupting this normal communication. The more neurons affected, the more severe the seizure.

Types of Seizures: Seizures are generally classified based on where they begin in the brain and how far they spread:

• Focal Seizures (Partial Seizures): These start in one area of the brain.
  • Focal Aware Seizures (Simple Partial Seizures): The person remains aware and responsive during the seizure. They may experience unusual sensations, movements, or thoughts.
  • Focal Impaired Awareness Seizures (Complex Partial Seizures): The person’s awareness is affected, and they may be confused or dazed, or perform repetitive, unconscious movements like lip smacking or chewing.
  • Focal to Bilateral Tonic-Clonic Seizures: A focal seizure that spreads to both sides of the brain, leading to a generalised tonic-clonic seizure.
• Generalised Seizures: These affect both sides of the brain from the start.
  • Absence Seizures (Petit Mal Seizures): Often seen in children, these involve brief staring spells or slight body movements like eye blinking or lip smacking, with a brief loss of awareness.
  • Tonic Seizures: Muscles suddenly stiffen, often affecting the back, arms, and legs. This can cause a person to fall.
  • Atonic Seizures (Drop Seizures): A sudden loss of muscle tone, often in the legs, leading to collapse.
  • Clonic Seizures: Characterised by rhythmic jerking movements, usually affecting the neck, face, and arms on both sides.
  • Myoclonic Seizures: Sudden, brief jerks or twitches of the arms and legs. The person usually remains conscious.
  • Tonic-Clonic Seizures (Grand Mal Seizures): The most common type of generalised seizure, involving loss of consciousness, body stiffness (tonic phase), and rhythmic shaking (clonic phase). They may also cause loss of bladder control or tongue biting.