Patients typically describe feelings of decreased alertness or sleepiness at times when they should be awake. This can sometimes be associated with sleep disorders such as sleep apnea and periodic limb movement during sleep (PLMS).
Restless Legs Syndrome (RLS)
This condition is experienced while the patient is awake and is typically more prominent later in the day or evening. Discomfort in the legs (creeping, crawling, tingling) may require subsequent movement of these limbs to acquire interim relief. The majority of patients who are diagnosed with Restless Legs Syndrome also have Periodic Limb Movement during sleep (PLMS).
Periodic Limb Movement During Sleep (PLMS)
A sleep disorder which involves repetitive movement of the limbs during sleep and may be associated with arousal activity in the EEG channels (brain waves). Some patients diagnosed with PLMS may also have Restless Legs Syndrome (RLS) as described above.
REM Sleep Behavior Disorder
A sleep disorder where increased muscle tone is associated with REM sleep thereby enabling the patient to enact dream content that otherwise is not usually possible.
Sleepwalking is associated with NREM sleep, more specifically slow wave sleep (stage N3). Typically, a patient does not recall any of the events that take place while sleep-walking.
Principally, insomnia refers to a person's difficulty initiating or maintaining sleep. In some cases, insomnia may be the result of an underlying sleep disorder such as sleep apnea or periodic limb movements, however, many other factors may contribute to insomnia (i.e. depression).