Photic (light) triggered focal sensory visual seizures - visual phenomena include lights, colored spots, formed visual hallucinations, or visual blurring/loss that moves across the visual field while the patient is aware. There may be head/eye version (as the patient tracks the visual phenomena).
Seizures are typically brief (<3 minutes), although prolonged seizures can occur. The frequency of seizures varies from individual to individual, relating to variations in an individuals threshold for light induction.