InsomniaInsomnia, also known as sleeplessness, is a sleep disorder where people have trouble sleeping. They may have difficulty falling asleep, or staying asleep for as long as desired. Insomnia is typically followed by daytime sleepiness, low energy, irritability, and a depressed mood. It may result in an increased risk of motor vehicle collisions, as well as problems focusing and learning. Insomnia can be short term, lasting for days or weeks, or long term, lasting more than a month.
Sleep paralysisSleep paralysis is a state, during waking up or falling asleep, in which one is conscious but is unable to move or speak. During an episode, one may hallucinate (hear, feel, or see things that are not there), which often results in fear. Episodes generally last no more than a few minutes. It can recur multiple times or occur as a single episode. The condition may occur in those who are otherwise healthy or those with narcolepsy, or it may run in families as a result of specific genetic changes.
Psychological traumaPsychological trauma (mental trauma, psychotrauma, or psychiatric trauma) is an emotional response caused by severe distressing events such as accidents, violence, sexual assault, terror, or sensory overload. Short-term reactions such as psychological shock and psychological denial are typically followed. Long-term reactions and effects include bipolar disorder, uncontrollable flashbacks, panic attacks, insomnia, nightmare disorder, difficulties with interpersonal relationships, and post-traumatic stress disorder (PTSD).
Post-traumatic stress disorderPost-traumatic stress disorder (PTSD) is a mental and behavioral disorder that develops from experiencing a traumatic event, such as sexual assault, warfare, traffic collisions, child abuse, domestic violence, or other threats on a person's life or well-being. Symptoms may include disturbing thoughts, feelings, or dreams related to the events, mental or physical distress to trauma-related cues, attempts to avoid trauma-related cues, alterations in the way a person thinks and feels, and an increase in the fight-or-flight response.
Sleep disorderA sleep disorder, or somnipathy, is a medical disorder of an individual's sleep patterns. Some sleep disorders are severe enough to interfere with normal physical, mental, social and emotional functioning. Polysomnography and actigraphy are tests commonly ordered for diagnosing sleep disorders. Sleep disorders are broadly classified into dyssomnias, parasomnias, circadian rhythm sleep disorders involving the timing of sleep, and other disorders including ones caused by medical or psychological conditions.
Mare (folklore)A mare (mære, mare, ; mara in Old High German, Old Norse, and Swedish) is a malicious entity in Germanic and Slavic folklore that walks on people's chests while they sleep, bringing on nightmares. The word mare comes (through Middle English mare) from the Old English feminine noun mære (which had numerous variant forms, including mare, mere, and mær). These in turn come from Proto-Germanic *marōn. *Marōn is the source of mara, from which are derived mara; mara; marra; mare; mare/mara, Dutch: (nacht)merrie, and German: (Nacht)mahr.
Dream interpretationDream interpretation is the process of assigning meaning to dreams. In many ancient societies, such as those of Egypt and Greece, dreaming was considered a supernatural communication or a means of divine intervention, whose message could be interpreted by people with these associated spiritual powers. In modern times, various schools of psychology and neurobiology have offered theories about the meaning and purpose of dreams.
DreamA dream is a succession of s, ideas, emotions, and sensations that usually occur involuntarily in the mind during certain stages of sleep. Humans spend about two hours dreaming per night, and each dream lasts around 5 to 20 minutes, although the dreamer may perceive the dream as being much longer than this. The content and function of dreams have been topics of scientific, philosophical and religious interest throughout recorded history.
FearFear is an intensely unpleasant emotion in response to perceiving or recognizing a danger or threat. Fear causes physiological changes that may produce behavioral reactions such as mounting an aggressive response or fleeing the threat. Fear in human beings may occur in response to a certain stimulus occurring in the present, or in anticipation or expectation of a future threat perceived as a risk to oneself.
SleepSleep is a state of reduced mental and physical activity in which consciousness is altered and sensory activity is inhibited to a certain extent. During sleep, there is a decrease in muscle activity, and interactions with the surrounding environment. While sleep differs from wakefulness in terms of the ability to react to stimuli, it still involves active brain patterns, making it more reactive than a coma or disorders of consciousness. Sleep occurs in repeating periods, during which the body alternates between two distinct modes: REM and non-REM sleep.