Non rapid eye movement or NREM sleep refers to the stages of sleep from 1 to 3. This is a form of sleep disorder that is harmful for a person. A person neither dreams nor the muscles get paralyzed as in REM sleep. In fact there is parasympathetic governance during the non rapid eye movement. There is no or little eye movement during these stages. The electroencephalographic (EEG), heart beat, breathing are slow and regular during these phases of sleep. The blood pressure of the person becomes low and there is no movement in the person while sleeping.

Various Stages of NREM Sleep

1. Stage 1 – This sleep disorder starts with slow eye movements. The theta wave takes the place of the alpha waves. People experience hypnic jerks during shifting to the first stage. People when wake up in this phase live with the perception that they are fully awake.
2. Stage 2 – In this phase, there is no eye movement. Dreams are either rare or there are no dreams experienced by the person. The patient can be easily awakened from his or her sleep. The electroencephalographic recordings show "K - complexes" and "sleep spindles" during the second stage.
3. Stage 3 – During this stage of NREM sleep the person is in a deep sleep and slow wave sleep. This stage was initially divided into stages 3 and 4. A person more often dreams in this stage but the count of dreams is lesser than that in REM sleep. The slow wave sleep dreams are vibrant, incoherent and are less memorable. The occurrence of parasomnias is very common in this last stage.

The sleep disorder is caused by a physiological activation in which the person's brain is caught between the stages of falling asleep and waking from sleep. The autonomous nervous system, cognitive process and motor system are activated during sleep or while the person wakes up from sleep. NREM sleepis very common during the childhood of a person but it reduces as they grow. The most common things that happen with the person are:

• Sleep walking – It is very common with people belonging to the ages of 11 and 12 years.
• Night fears – People awake in panic or with a scream. The patient suffers a lot. Continuous consolation is of no use at this stage. The patient may end up hurting him or herself. The person often experiences amnesia after the terror.
• Sudden awakening – It is very common in children. They wake up due to terrible crying or irregular thrashing. This is described by movements in bed.
• Restless Leg Syndrome – The person suffers from itching, burning or uncomfortable feeling in the legs during the sleep. The sleep is disturbed when they get up to scratch their legs.

NREM sleepdisorder is very problematic for a person. It causes sleep disruption and the person doesn't get sound sleep for relaxed body and mind. His overall health suffers due to this particular kind of sleep disorder.