Sleep modulation of interictal spike configuration in untreated children with partial seizures

Spontaneous changes in interictal spike morphology were evaluated before initiation of antiepileptic drug (AED) therapy in 38 children with uncontrolled partial seizures. Nonrapid eye movement (NREM) sleep during the first third of the night was associated with spikes of higher amplitude, longer duration, and lower degree of sharpness than those observed in wakefulness or REM sleep. Spike amplitude decreased in subsequent NREM epochs, but duration and sharpness remained relatively consistent. A NREM/REM modulatory pattern was identified, with REM periods exhibiting spikes of decreased amplitude, shorter duration, and increased sharpness as compared with NREM periods in each third of the night. The spike changes associated with REM sleep are similar to the alterations previously described as occurring coincidentally with attainment of seizure control and thus may reflect inherent modulation of epileptogenicity in synchrony with sleep cycles.