What symptom characterizes Todd paralysis?

Todd paralysis is characterized by postictal focal weakness, which refers to weakness affecting a specific part of the body that occurs following a seizure. This condition typically manifests after a focal seizure or a generalized seizure, where the individual may have temporary neurological deficits in specific muscle groups. The weakness can last from minutes to hours and usually resolves completely, reflecting the aftermath of the seizure rather than being a permanent neurological impairment.

The mechanism behind Todd paralysis involves temporary dysfunction in the brain regions that control motor function, particularly if a seizure has spread to those areas. This phenomenon illustrates the complex relationship between electrical activity in the brain during seizures and the subsequent motor control deficits that can appear.

The other options describe symptoms not typically associated with Todd paralysis. Loss of consciousness is common during seizures but does not define Todd paralysis itself. Muscle spasms may occur during seizures or in other contexts but are not characteristic of the postictal state that defines Todd paralysis. Intense headaches can occur in various situations but are not a defining symptom of the paralysis that follows a seizure. Thus, the defining symptom of Todd paralysis is indeed the postictal focal weakness that follows a seizure.