| N | Narcolepsy |
| N Sleep | Non-Rapid Eye Movement (NREM) sleep. The primary phase for 75% to 80% of an adult’s sleep time. It is made up of three sleep stages. |
| Nap | Short period of planned sleep generally obtained at a time separate from the major sleep period. |
| Narcolepsy | Sleep disorder characterized by excessive sleepiness cataplexy sleep paralysis hypnogogic hallucinations and an abnormal tendency to pass directly from wakefulness into REM sleep. |
| NARCOLEPSY (nar-co-lep-si) | A cause of daytime sleepiness due to an inherited disorder of the control of dreaming sleep. Has to be differentiated from sleep apnoea periodic leg movements and other rarer causes of daytime sleepiness. |
| Nasal Airflow/Nasal Ventilation | Recording of the complete respiratory cycle by measuring inspiratory and expiratory airflow |
| NASAL CPAP (nasal see-pap) | The process of delivering a continuously raised airway pressure via a mask on the nose. Hence nasal Continuous Positive (as opposed to negative) Airway Pressure treatment. |
| NASAL INTERMITTENT POSITIVE PRESSURE VENTILATION (NIPPV) | Overnight assisted breathing with a machine that intermittently inflates the lungs. In contrast to nasal CPAP which provides a constant pressure to hold open the upper airway. |
| Nasal pressure transducer | Measures airflow into and out of your nose It can detect a hypopnea because it is sensitive even to minor changes. It is used with a cannula. |
| National Commission on Sleep Disorders Research (NCSDR) | The commission (created by the U.S. Congress in 1990) conducted a comprehensive study of the social and economic impact of sleep disorders in America and made recommendations based on its findings to the Congress in January 1993 |
| NCSDR | National Commission on Sleep Disorders Research |
| NECK CIRCUMFERENCE | One of the best predictors of whether there are upper airway problems during sleep. More than 16" - could be a snorer more than 17" could have sleep apnoea. One can still have sleep apnoea with smaller necks but it is less common. |
| Neurology | Branch of medicine that referring to the nervous system and its diseases. |
| Neurotransmitters | Endogenuous chemical components that are released from axon terminals of one neuron and transmit the signal to the next neuron by combining with its receptor molecules. Neurotransmitters important in the control of sleep and wakefulness include: norepinephrine serotonin acetylcholine dopamine adrenaline and histamine. |
| Night Terrors | Also known as sleep terrors or pavor nocturnus. Night terrors are characterized by an incomplete arousal from slow wave sleep. If the individual is awakened during a night terror he/she is usually confused and does not remember details of the event. Night terrors are different from nightmares; if an individual is awakened during a nightmare he/she functions well and may have some recall of the nightmare. |
| Nightmare | Unpleasant and/or frightening dream occurring in REM sleep (different from a night terror). |
| NMH | Neurally Mediated Hypotension |
| NN | Narcolepsy Network |
| Nocturia | Excessive often frequent urination during the night. |
| NOCTURIA (nock-tur-ee-ah) | Excessive urine production at night. Seen in sleep apnoea quite often. |
| Nocturnal | "Of the night;" pertaining to events happening during sleep or the hours of darkness. |
| Nocturnal Confusion | Episodes of delirium and/or disorientation near or during nighttime sleep; often seen in victims of Alzheimers Disease and more common in the elderly. |
| Nocturnal Enuresis (Bedwetting) | Urinating while asleep. |
| Nocturnal sleep-related eating disorder (NS-RED) | Getting up during the night and eating while sleepwalking. No recall in the morning. |
| NON REM SLEEP | See sleep stages. |
| Non-Invasive | Medical procedure not penetrating the skin or a body cavity. |
| Nose Pads | Foam pads to hold the mask at a certain distance of the bridge of the nose. |
| NPT | Nocturnal Penile Tumescence |
| NREM | Non-Rapid Eye Movement (sleep) |
| NREM or non-REM sleep | Characterized by slower and larger brain waves and little or no dream behavior; quiet sleep slow-wave sleep; approximately 80% of sleep. |
| NREM Sleep Intrusion | Brief period of NREM sleep patterns appearing in REM sleep; a portion of NREM sleep not appearing in its usual sleep cycle position |
| NS-RED | Nonturnal sleep related eating disorder |
