A 5-year-old boy presents with a history of three stereotyped seizures over 6 months, each occurring during sleep or drowsy states. Each episode featured prominent autonomic symptoms (projectile vomiting, pallor, diaphoresis), lasted 20–25 minutes, and included eye deviation and brief unilateral clonic movements before generalization. Between episodes, he is developmentally normal with a completely normal neurologic examination. Brain imaging and metabolic studies are normal. EEG is performed to confirm the suspected diagnosis of Panayiotopoulos syndrome. The EEG shows the characteristic finding marked **B** in the diagram. Which of the following best describes the clinical significance of this EEG finding in this patient?