Chronic sleep disorders in childhood, which affect some 70% of children with developmental or psychological disorders, are under-reported and under-treated. Sleep-phase disruption is also common among adolescents, whose school schedules are often incompatible with their natural circadian rhythm. Effective treatment begins with careful diagnosis using sleep diaries and perhaps sleep studies. Modifications in sleep hygiene may resolve the problem, but medical treatment is often warranted.[35]
Neurodegenerative diseases have been often associated with sleep disorders, mainly when they are characterized by abnormal accumulation of alpha-synuclein, such as multiple system atrophy (MSA), Parkinson's disease (PD) and Lewy body disease (LBD).[21][22][23][24][25][26][27] For instance, people diagnosed with PD have often presented different kinds of sleep concerns, commonly regard to insomnia (around 70% of the PD population), hypersomnia (more than 50% of the PD population), and REM sleep behavior disorder (RBD) - that may affect around 40% of the PD population and it is associated with increased motor symptoms.[21][22][23][24][25][27] Importantly, RBD has been also highlighted as a strong precursor of developing dementia in PD patients over several years in prior, which seems to be a great opportunity for improving the treatments of the disease.[22][24]

This clock is a small part of the brain called the suprachiasmatic nucleus of the hypothalamus. It sits just above the nerves leaving the back of our eyes. Light and exercise "reset" the clock and can move it forward or backward. Abnormalities related to this clock are called circadian rhythm disorders ("circa" means "about," and "dies" means "day").

What to do: Talk to experts about sleeplessness, and you'll be told to practice good "sleep hygiene." What this means is that you need to take your lack of sleep seriously and look at your sleep habits and physical surroundings to see what might be preventing you from sleeping well. Start with your evening habits: What do you do in the hours before bed? Eliminate late-night eating, drinking, and computer use and your chances of falling asleep quickly and sleeping soundly are much greater. Use the last hour before bed to do things that relax you, like taking a warm bath, meditating, or reading.
Competence in sleep medicine requires an understanding of a myriad of very diverse disorders, many of which present with similar symptoms such as excessive daytime sleepiness, which, in the absence of volitional sleep deprivation, "is almost inevitably caused by an identifiable and treatable sleep disorder", such as sleep apnea, narcolepsy, idiopathic hypersomnia, Kleine–Levin syndrome, menstrual-related hypersomnia, idiopathic recurrent stupor, or circadian rhythm disturbances.[52] Another common complaint is insomnia, a set of symptoms which can have a great many different causes, physical and mental. Management in the varying situations differs greatly and cannot be undertaken without a correct diagnosis.[citation needed]
Narcolepsy is a sleep disorder that involves excessive, uncontrollable daytime sleepiness. It is caused by a dysfunction of the brain mechanism that controls sleeping and waking. If you have narcolepsy, you may have “sleep attacks” in the middle of talking, working, or even driving. Although no cure yet exists, a combination of treatments can help control symptoms and enable you to enjoy many normal activities.
What to do: See a doctor, who will likely first check you for underlying conditions related to PLMD. Diabetes, thyroid disorders, anemia, and a number of other conditions can cause PLMD. If you do have another condition, the doctor will treat it and see if the PLMD goes away. The next step is to control the involuntary movements with medication. Drugs that suppress muscle contractions work well for preventing PLMD. The doctor may also prescribe medication to help you sleep more deeply, with the idea of preventing the involuntary movements from keeping you in light sleep.
Sleep apnea, obstructive sleep apnea, obstruction of the airway during sleep, causing lack of sufficient deep sleep, often accompanied by snoring. Other forms of sleep apnea are less common.[10] Obstructive sleep apnea (OSA) is a medical disorder that is caused by repetitive collapse of the upper airway (back of the throat) during sleep. For the purposes of sleep studies, episodes of full upper airway collapse for at least ten seconds are called apneas[11]

According to one meta-analysis, the two most prevalent sleep disorders among children are confusional arousals and sleep walking.[57] An estimated 17.3% of kids between 3 and 13 years old experience confusional arousals.[57] About 17% of children sleep walk, with the disorder being more common among boys than girls.[57] The peak ages of sleep walking are from 8 to 12 years old.[57] A different systematic review offers a high range of prevalence rates of sleep bruxism for children. Between 15.29 and 38.6% of preschoolers grind their teeth at least one night a week. All but one of the included studies reports decreasing bruxist prevalence as age increased as well as a higher prevalence among boys than girls.[58]
What to do: If you suspect you have a circadian rhythm disorder, take steps to get your body onto a regular sleep schedule. Choose a bedtime and wake-up time that work for you, and follow the same routine each day, even on weekends. This can be tough for those who have to get up early during the week but like to stay up later on weekends, but do your best to craft a compromise between your work week and weekend habits. The important thing is to avoid the trap of sleeping from 10 p.m. to 6 a.m. during the week, then suddenly shifting to late nights and late mornings on the weekends. This will inevitably leave you with insomnia on Sunday night, which in turn sets you up to start the week exhausted on Monday morning.