What term describes involuntary muscle contractions that can occur suddenly?

The term that describes involuntary muscle contractions that can occur suddenly is a seizure. Seizures are episodes of uncontrolled electrical activity in the brain that can lead to changes in behavior, movements, feelings, or consciousness. During a seizure, muscle contractions can be intense and might involve all of the body or just part of it. These sudden episodes are often seen in conditions like epilepsy but can also result from various medical issues or triggers.

Other terms might describe different types of muscle contractions, like spasms, which are sudden, involuntary muscle contractions but are typically localized and may not lead to the broader neurological effects or loss of consciousness associated with seizures. Tremors refer to rhythmic shaking movements, while convulsions can be characterized as violent shaking and may occur during seizures but are not synonymous with the broader classification of seizures.