This review addresses the effects of subclinical localized epileptiform discharges during sleep in children with benign childhood epilepsy with centrotemporal spikes (BCECTS) on cognition and behavior. A diversity of educational deficits, behavioral impairments, language delay, and neuropsychological test results have been reported in children with BCECTS. The occurrence of atypical seizure characteristics seems to be related to language delay, and several atypical EEG characteristics are related to cognitive or behavioral problems. It remains to be shown whether treatment of nocturnal discharges in children with BCECTS is indicated to improve cognitive and behavioral problems.