Study on 14 and 6 per second positive spikes during nocturnal sleep

Abstract

1. 1. Eleven patients showing 14 and 6/sec positive spikes (14 and 6 PS) during routine EEG examination and with diphenhydramine activation were studied during nocturnal sleep. Two patients who showed this pattern only during nocturnal sleep and another four cases with bilateral synchronous 5–6/sec spike and wave paroxysms were also similarly studied. The incidence (per minute) of the 14 and 6 PS and the spike and wave paroxysms during different stages of sleep was calculated and the discharging patterns were classified into 4 types according to their preferential occurrence in one or the other stage. 2. 2. All the patients who showed 14 and 6 PS during routine EEG and diphenhydramine activation also exhibited this pattern during the nocturnal sleep recording. 3. 3. In more than half of the cases, 14 and 6 PS appeared most frequently during the stage 1-REM period and the incidence rates during the spindle phase were very low. The bilateral synchronous spike and wave paroxysm, on the other hand, tended to show high incidence during the waking state and stages 1, 2 and 3, and the incidence in the stage 1-REM was relatively low. 4. 4. It was assumed that the 14 and 6 PS were not associated with sleep spindles. It was also revealed that the discharging pattern of the 14 and 6 PS during nocturnal sleep was different from that of both the centrencephalic and focal cortical seizure discharges. The possible mechanisms of the enhancement of the 14 and 6 PS during stage 1-REM were discussed.