What characterizes a tonic-clonic seizure?

A tonic-clonic seizure, also known as a grand mal seizure, is characterized by a combination of intense muscle rigidity followed by rhythmic jerking movements. The seizure typically begins with a tonic phase, where there is a sudden loss of consciousness and the person's body becomes stiff due to muscle contractions. This is followed by the clonic phase, where the body exhibits rhythmic jerking motions as the muscles alternately contract and relax. The individual loses awareness during the seizure and commonly experiences a postictal state afterward, which can include confusion, fatigue, and disorientation.

The other options do not accurately describe a tonic-clonic seizure. Focal deficits with preserved cognition align more with focal seizures, which do not involve loss of consciousness. Intermittent staring spells with no postictal state are characteristic of absence seizures, which involve brief lapses in awareness rather than the intense activity seen in tonic-clonic seizures. Lastly, spasms primarily in the hands and face suggest a different type of seizure, such as myoclonic seizures, which are not representative of the full-body presentation typical of tonic-clonic seizures.