A sleep disorder is characterized as the disturbance in time, quality, amount, or behavior associated with sleep. Sleep disorders are classified according to two major types, dyssomnia and parasomnias.
The dyssomnia caterogy involves sleeping disorders where an individual finds it difficult to sleep or to remain asleep. The parsasomias category involves sleeping disorders where an individual experiences abnormal or unnatural movement, behavior, emotion, perception, and dreams which occur when an individual is falling asleep, sleeping, between stages of sleep, or during waking from sleep.
The dyssomnia category of sleep disorders consists of the following:
Insomnia. An individual has difficulty falling asleep or remaining asleep. There are three types of insomnia. Transient insomnia which lasts less than one week; Short-term insomnia when a person is unable to consistently sleep well for a period of one to three weeks; and Chronic insomnia when a person is unable to sleep well for a period of longer than three weeks.
Hypersomnia. An individual experiences episodes of excessive daytime sleepiness or prolonged sleep during the night. These individuals feel the need to nap several times during the day, but the naps do not ease the feeling of sleepiness. Hypersomnia usually occurs between the ages of 15 and 30.
Narcolepsy. This is a chronic sleep disorder and a chronic neurological disorder that is caused by the inability of an individual's brain to regulate sleep-wake cycles properly. An individual suffering with narcolepsy experiences daytime sleepiness and uncontrollable bouts of falling asleep during the day. Individuals with narcolepsy may also experience cataplexy which is a sudden loss of muscle tone that can cause physical changes such as slurred speech or muscle weakness; suffer from hypnagogic hallucinations (a dream-like auditory or visual hallucination experienced while dozing or falling asleep); or sleep paralysis where the individual temporarily is unable to speak or move while falling asleep or waking.
Circadian rhythm sleep disorders. This disorder occurs when there is a change in an individual's sleep/wake patterns such as jet lag or shift work schedule change.
Restless leg syndrome. This is a neurological disorder where an individual experiences an unpleasant sensation in their leg (such as a creeping or tugging feeling). These sensations usually occur when a person is either in a sitting or horizontal position as when sleeping. Depending on severity these sensations can simply be irritating or they can be very painful.
Sleep apnea. This is actually a very common disorder though often not diagnosed unless the individual brings it to a doctor's attention and undergoes a sleep study test. It occurs when an individual has one or more pauses in breathing while sleeping. The breathing pauses for seconds or minutes depending on the severity of an individual's sleep apnea. When normal breathing starts again it is often accompanied by a loud snort or a choking sound. This is an ongoing problem and the individual with sleep apnea does not get good quality sleep, which causes excessive sleepiness during the day.
The parasomnia category of sleep disorders consists of the following:
Nightmare disorder. This disorder occurs when an individual is awakened by a frightening dream. It most commonly occurs in young children thought it can affect individuals at any age.
Confusional arousals. This disorder consists of thrashing or inconsolable crying. It most commonly occurs in children.
Sleepwalking (also referred to as somnambulism). This disorder consists of an individual making complex movements during sleep which includes walking. It most commonly occurs in children though it can affect individuals at any age.
Night Terrors (also referred as Sleep Terror). This disorder occurs when an individual wakes up screaming or crying. It most commonly occurs in young children though it can affect individuals at any age.
Teeth grinding (also referred to as bruxism). This disorder occurs when an individual grinds their teeth while they sleep. Over time the teeth grinding and wear down and cause teeth to fracture. Jaw pain can also occur.