Differential effects on fast and slow spindle activity, and the sleep slow oscillation in humans with carbamazepine and flunarizine to antagonize voltage-dependent Na+ and Ca2+ channel activity.

Study Objectives: Sleep spindles play an important functional role in sleep-dependent memory consolidation. They are a hallmark of non-rapid eye movement (NREM) sleep and are grouped by the sleep slow oscillation. Spindles are not a unitary phenomenon but are differentiated by oscillatory frequency and topography.

Grouping of MEG gamma oscillations by EEG sleep spindles.

Studies have revealed an association between EEG sleep spindles and processing of memories during sleep. Here we investigated whether there is a temporal relation between sleep spindles and MEG oscillatory activity in the gamma frequency band (>30 Hz) which is considered to reflect local cortical processing of memory representations. MEG and simultaneous EEG (at Cz) were obtained in subjects during sleep together with standard polysomnography.

Sleep selectively enhances memory expected to be of future relevance.

The brain encodes huge amounts of information, but only a small fraction is stored for a longer time. There is now compelling evidence that the long-term storage of memories preferentially occurs during sleep. However, the factors mediating the selectivity of sleep-associated memory consolidation are poorly understood.