Hypnagogic Hallucinations and Sleep Paralysis
Hypnagogic hallucinations and sleep paralysis hypnagogic hallucinations are brief periods of dreaming between the stages of sleep and consciousness. These dreams can be frightening and can often cause a sudden jerk and arousal just before sleep onset. For example, you may see yourself falling and then, just before impact, awaken with a sudden jerk.
Sleep paralysis is the sensation of feeling paralyzed upon awakening, usually immediately following a dream. This is commonly associated with the loss of muscle tone during dreams, called atonia. This loss of muscle tone during the dreaming stage prevents one from acting out his or her dreams. Hypnagogic hallucinations and sleep paralysis can occur together. Although commonly seen in people with narcolepsy, they can also affect others, especially those individuals who are sleep-deprived. While they can be frightening, these events are not physically dangerous and usually last only a few minutes.
Nocturnal seizures are usually tonic/clonic (grand mal). Muscles will stiffen (tonic phase) and then extremities will jerk and twitch (clonic phase). Bladder control may be lost. Consciousness is regained slowly. These seizures might occur just after a person has fallen asleep, just before waking, during daytime sleep, or while in a state of drowsiness. People who experience nocturnal seizures may find it difficult to wake up or to stay awake. Although unaware of having had a seizure while asleep, they may arise with a headache, have temper tantrums, or display other destructive behavior throughout the day.
Nocturnal seizures are very uncommon and their mechanisms poorly understood. The majority of people with nocturnal seizures have idiopathic epilepsy. There is evidence that sleep enhances epileptic discharges in an electroencephalogram, a test that measures and records the brain’s electrical activity, though a person’s daytime recordings may appear to be normal. However, if a pattern of limiting seizures to the hours of slumber is maintained, the chance of them occurring during the daytime is greatly reduced.
REM Behavior Disorder
REM Behavior Disorder is the ability to act out your dreams. The obvious problem with acting out your dreams is the potential to cause injury. All body muscles, with the exception of those used in breathing, are usually paralyzed during REM (dream) sleep. In some cases this paralysis is incomplete or absent, thus allowing dreams to be acted out. Behavior such as this can be violent and result in serious injuries to the victim and bed-partner. After awakening the sleeper will usually be able to recall vivid dreaming.
Bruxism is grinding, gnashing or clenching your teeth during sleep or situations that make you feel anxious or tense. Bruxism most often occurs in the early part of the night and can disturb sleep partners. Some people brux so loudly that they can't duplicate the sound while awake or relaxed. Others make no sound while bruxing and often deny having the condition even after tooth or jaw damage is discovered.
Rhythmic-Movement Disorder is seen most often in younger children, yet can also occur in adults. The movements usually consist of recurrent head banging, head rolling and body rocking. The individual may also moan or hum during these movements. Typically these movements will occur just before sleep begins or during sleep.