Computer analysis of electroencephalography (EEG) will be performed during wakefulness and all stages of sleep to determine if greater disease severity, sleepiness, sleep disruption, and neurocognitive impairment is associated with increased amounts of slow activity. Improvement in these related factors will be associated with normalizations of these parameters. For some of these quantitative measures, the findings may be more significant for particular brain regions; for example, frontal regions in the case of attention problems.