Nap means a short period of planned sleep during the daytime. This necessity in having a sleep during a day may be the result from a lack of nighttime sleep.
Narcolepsy is a kind of sleep disorder, when brief attacks of deep sleep can occur. This condition also includes such symptoms as abnormal tendency to pass right from awakefulness into REM sleep, cataplexy, excessive sleepiness, hypnogogic hallucination, overwhelming daytime sleepiness, which may take place even if a person had an adequate nighttime sleep, and even sleep paralysis.
Narcotic is the name of any addictive drug, which acts by dulling all the senses and inducing sleep.
Natural Short Sleeper is called a person, who can sleep much less in a 24 – hour period, in comparison with other people of his or her age group, habitually and spontaneously; while sleeping substantially less than other, this person would not experience any excessive sleepiness. Short sleepers also have a tendency to spontaneous awakening. Of no doubt, the range or variation for every individual’s need for sleep is broad enough, still any typical adult person requires about 7 – 10 hours of sleep each night. However, as for short sleepers, they have a daily total sleep time of less then 75% of the age – related norm.
Nightmare means any unpleasant and / or frightening dream, which usually makes the sleeper awake. Unlike night terrors, nightmares take place during REM sleep.
Night Terror is the term, which is used to describe incomplete arousal from slow wave sleep, and which is accompanied by a condition of intense fear and agitation sometimes experienced, especially by children, on awakening from a stage of sleep, which is not associated with dreaming, but which is characterized by extremely vivid hallucinations. In contrast to nightmares, when a person can recall at least part of his or her dream, if someone has night terror, he or she usually awakens in terror with feelings of anxiety and fear, though this person is not able to remember any incident, which might have served as a provocation to those feelings.
Nocturial means anything, which is relating to or which is taking place at nighttime.
Nocturial Sleep – Related Eating Disorder (NS – RED) – is called eating something while sleepwalking. As a rule the person is not able to remember the process of eating when he or she wakes up.
Non–REM Sleep (NREM) is a normal part of every healthy person’s sleep. This sleep period accounts typically 75 – 80% of the entire sleep time. The NREM Sleep is characterized by somewhat slower and larger brain waves, rather than in REM.
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