Five Common Sleep Phenomena

The mysteries of the sleeping mind are some of the hardest things to understand. Sleep in itself is only becoming less mysterious in recent years. Questions like “Why do we sleep?” and “Do we really need sleep?” are finally being answered. However, some sleep phenomena remain unexplained. Moreover, in spite of being very scary for the sufferer, there are skeptics.

The following five sleep phenomena are understood, to an extent. As you’ll see, we do know the common symptoms and even some common causes of them. Nonetheless, we can hardly understand what causes the sleeping mind to behave in such ways.

Sleep Phenomenon: Hypnopompic/Hypnagogic Hallucinations

Hypnopompic and hypnagogic hallucinations are, quite simply, hallucinations that occur while falling asleep or waking from sleep. Hypnagogic hallucinations occur while falling asleep and hypnopompic while waking. They are sometimes accompanied by sleep paralysis. These hallucinations are, more often than not, no indication that the sufferer has a mental condition.

Hypnagogic and hypnopompic hallucinations can be auditory, visual, tactile or kinetic. A common sleep hallucination is the sensation of falling causing you to jerk yourself awake and other such mild sleep disturbances. Many people will experience this mild form of hypnagogic or hypnopompic hallucination in their lifetimes. However, they can also be quite disturbing. Some people may see a person or creature. These hallucinations are often described as very realistic.

Drug abuse has been linked to hypnagogic and hypnopompic hallucinations. Certain medications, medical conditions and sleep disorders have also been linked to hypnopompic and hypnagogic hallucinations. However, none of these things must be present for a person to experience these hallucinations. They may happen to anyone, at any time, and can be chronic or isolated.

Sleep Phenomenon: Lucid Dreaming

Lucid dreaming is probably the coolest of all sleep phenomena. Many people actually dedicate a great deal of time attempting to achieve lucid dreams. Lucid dreams are characterized by the awareness that you are dreaming. If you have ever been dreaming and suddenly realized that you were dreaming, then you have experienced a lucid dream. This may also be accompanied with the ability to control your surroundings within the dream. Virtually anything is possible with this control during lucid dreaming.

Sleep Phenomenon: Night Terrors

Night terrors are often described as an awful experience. They are moments of terror that wake the sufferer from sleep. They are not always remembered the following day, but loved ones often become aware of the sufferer’s sleep terrors when they scream. It is very common for a person having night terrors to scream while they are waking in this state.

Symptoms of night terrors are sweating, fast heart beat, sudden waking, confusion upon waking and screaming or crying. Sufferers may see frightening images upon waking. The cause of night terrors is unknown, but they are sometimes associated with some medical conditions, stress or some medications. They are most common in children aged three to five, but may occur at any age.

Night terrors typically last between five and 20 minutes. They occur during stage four of sleep and not during REM sleep. This is one of the things that differentiate night terrors from nightmares. In fact, people suffering from night terrors usually do not recall any sort of nightmare that may have triggered their symptoms, if they can recall the incident at all.

Sleep Phenomenon: Sleepwalking

Sleepwalking, also known as somnambulism, is exactly what it sounds like. Quite simply, it is walking while sleeping. However, sleepwalking does have some other characteristics.

Sleepwalkers may walk around calmly or they may run around and behave frantically. They nearly always have their eyes open when the event occurs, but their eyes are unfocused. They can speak, but their speech is often incoherent. They also may not answer if they are spoken to while they are having an episode of sleepwalking.

Sleepwalking often occurs in young children and teens, but it may occur at any age. It is sometimes associated with certain medications, medical conditions and psychiatric disorders. It typically occurs in sleep stages three and four.

Sleep Phenomenon: Sleep Paralysis

Sleep paralysis is another frightening sleep phenomenon. It happens when you gain consciousness during sleep, but you cannot move. It may be coupled with hallucinations, which can be disturbing. Some people who have experienced sleep paralysis believe that they have been abducted by aliens or have been possessed.

People of any age may experience sleep paralysis at any time. Experiences can be recurrent or isolated. Sleep paralysis may be associated with some medical conditions, medications or other sleep disorders.

These are only five of the most common sleep phenomena. There are many more that a person may experience. Not all of them require medical attention or treatment. Nonetheless, if any of these sleep disturbances, or any others, are distressing enough to cause significant stress, if the sufferer is losing a great deal of sleep or if they are acting out violently, medical attention may be necessary.

*This article is not meant for the purpose of self-diagnosis. I am not a medical professional. I'm just a lucid dreamer who is interested in weird stuff, so consult your doctor if you need help.


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Sleep Paralysis, retrieved 12/30/09,

*Personal Knowledge

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What are Hypnopompic Hallucinations?, retrieved 12/30/09,

Poveglia Island: Mystery or Misrepresentation?

Image of Poveglia Island canal
Courtesy of Chris 73
Poveglia Island is a very small island that is located in Italy’s Venetian Lagoon. The island itself is rather run-of-the-mill. It is covered with a smattering of foliage, as well as some run down buildings, a water tower and a bell tower that appear to be going back to nature. Poveglia Island is split in two by a small canal that runs straight through it. The canal has walkways over it. On one side, there are the deteriorating buildings, on the other, nothing but greenery and grass. However, there is a more interesting aspect of the island that one wouldn’t suspect by looking at it, though some say you can tell when you are there, and that is the island’s supposedly sinister history.

Poveglia Island was once inhabited by a small community. However the island was abandoned around 1380, during the War of Chioggia. Later, as the Bubonic Plague spread through Europe and inevitably into Venice, Poveglia Island was reportedly used as a dump for bodies and as a lazaretto. Even worse, there are rumors that live victims of the Bubonic Plague were also brought to the island and left there. Some of the rumors say that the live victims were burned with the dead or left in mass graves full of dead bodies. There seem to be no official records of this, though. If it were true, the best fate for the live victims may very well have been fire. Bubonic Plague is a horrible bacterial infection that affects the lymph nodes. Without modern treatment, a painful death is nearly inevitable. If the victims didn’t die, they would surely have starved to death on the island.

The next phase of Poveglia Island’s history supposedly began in the early 1920's. At this time, either a menacing insane asylum or a harmless retirement community was built there. The story behind this supposed asylum makes the retirement community seem to be the more likely of the two. Lovers of the paranormal claim that evil experiments were conducted on patients of the asylum by a crazed doctor. The patients were also supposedly haunted by the plague victims who were buried on Poveglia Island. The doctor himself reportedly fell victim to these hauntings and threw himself out of the island’s bell tower. The legend goes on to say that his suicide was witnessed by an asylum worker, who said that the doctor survived the fall and was then suffocated by a mysterious mist. The asylum or retirement community on Poveglia Island was closed sometime in the 1960's.

Whether you believe any of the stories surrounding Poveglia Island or not, there is certainly something mysterious about the place. Many people have claimed to sense a presence or worse while they were visiting the island. Today, it is owned by the government and closed to the public. It is currently being used for vineyards. Whether or not the grapes that are grown there are fertilized by the bodies of the more than 150,000 people who have reportedly died there is a matter of speculation. Nonetheless, you may want to check the label of your Italian wine very closely.


shezab, Poveglia Island, retrieved 2/27/10,

Poveglia Island of Horror, retrieved 2/27/10,