 Evidence from the Sleep Heart Health Study suggests that nocturnal arousals from sleep impact heart rate variability and sleep disorders associated with frequent nocturnal arousals, including restless legs syndrome RLS, increase the risks of developing cardiovascular disease. The majority of RLS patients, once asleep, exhibit frequent periodic limb movements PLMs, which cause electroencephalographic EEG arousals and sleep fragmentation resulting in poor quality of sleep and daytime consequences. PLMs are also reported to increase heart rate.The precise nature of the relationship between PLMs and their impact on heart rate and blood pressure is not clear. This may relate to the fact that PLMs are scored as either present or absent and without accounting for the differences in intensity of muscle activity during individual PLMs and intensity of associated arousals. In fact PLMs have been reported to vary from barely visible to very intense changes in the anterior tibialis electromyogram EMG. This study will evaluate the effects of gabapentin encarbil GEn on intensity of cortical arousals associated with PLMs using a newly developed computer assisted scoring system which allows for scaling microarousals in the EEG. The anterior tibialis EMG intensity, continuous blood pressure and heart rate will be measured. 