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Alice in Wonderland Syndrome (also known as Todd's syndrome, or lilliputian hallucinations) is a disorienting neurological condition that affects human perception. People experience micropsia, macropsia, pelopsia, teleopsia, or size distortion of other sensory modalities. It is often associated with migraines, brain tumors, and the use of psychoactive drugs. It can also be the initial symptom of the Epstein–Barr virus (see mononucleosis). Anecdotal reports suggest that the symptoms are fairly common in childhood, with many people growing out of them in their teens. It appears that AiWS is also a common experience at sleep onset, and has been known to commonly arise due to a lack of sleep. AiWS can be caused by abnormal amounts of electrical activity causing abnormal blood flow in the parts of the brain that process visual perception and texture. ==Signs and symptoms== The hallmark sign of Alice in Wonderland syndrome (AIWS) is a migraine, and AIWS may in part be caused by the migraine. AIWS affects the sense of vision, sensation, touch, and hearing, as well as one's own body image. A prominent and often disturbing symptom are experiences of altered body image. The person may find that they are confused as to the size and shape of parts of (or all of) their body. They may feel as though their body is expanding or getting smaller. Alice in Wonderland syndrome also involves perceptual distortions of the size or shape of objects. Other possible causes and signs of the syndrome include migraines, use of hallucinogenic drugs, and infectious mononucleosis.〔"Alice in Wonderland syndrome." Taber's Cyclopedic Medical Dictionary. Philadelphia: F.A.Davis Company, 2009. Credo Reference. Web. 24 September 2012.〕 Patients with certain neurological diseases have experienced similar visual hallucinations.〔"Alice in Wonderland syndrome." Mosby's Dictionary of Medicine, Nursing & Health Professions. Philadelphia: Elsevier Health Sciences, 2009. Credo Reference. Web. 24 September 2012.〕 These hallucinations are called "Lilliputian," which means that objects appear either smaller or larger than they actually are.〔"Hallucinations." The Concise Corsini Encyclopedia of Psychology and Behavioral Science. Hoboken: Wiley, 2004. Credo Reference. Web. 24 September 2012.〕 Patients may experience either micropsia or macropsia. Micropsia is an abnormal visual condition, usually occurring in the context of visual hallucination, in which affected persons see objects as being smaller than those objects actually are.〔"micropsia." Mosby's Emergency Dictionary. Philadelphia: Elsevier Health Sciences, 1998. Credo Reference. Web. 24 September 2012.〕 Macropsia is a condition where the individual sees everything larger than it actually is.〔"macropsia". Collins English Dictionary. London: Collins, 2000. Credo Reference. Web. 24 September 2012.〕 The relationship, if any, between the syndrome and mononucleosis remains unknown. One 17-year-old male described his odd symptoms. He said, "quite suddenly objects appear small and distant (teliopsia) or large and close (peliopsia). I feel as I am getting shorter and smaller 'shrinking' and also the size of persons are not longer than my index finger (a lilliputian proportion). Sometimes I see the blind in the window or the television getting up and down, or my leg or arm is swinging. I may hear the voices of people quite loud and close or faint and far. Occasionally, I experience attacks of migrainous headache associated with eye redness, flashes of lights and a feeling of giddiness. I am always conscious to the intangible changes in myself and my environment." The eyes themselves are normal, but the person will often 'see' objects as the incorrect size, shape or perspective angle. Therefore, people, cars, buildings, houses, animals, trees, environments, etc., look smaller or larger than they should be, or that distances look incorrect; for example a corridor may appear to be very long, or the ground may appear too close. The person affected by Alice in Wonderland Syndrome may also lose the sense of time, a problem similar to the lack of spatial perspective. In other words, time seems to pass very slowly, akin to an LSD experience. The lack of time, and space, perspective leads to a distorted sense of velocity. For example, one could be inching along ever so slowly in reality, yet it would seem as if one were sprinting uncontrollably along a moving walkway, leading to severe, overwhelming disorientation. This can then cause the person to feel as if movement, even within his or her own home, is futile. In addition, some people may, in conjunction with a high fever, experience more intense and overt hallucinations, seeing things that are not there and misinterpreting events and situations. Other minor or less common symptoms may include loss of limb control and general dis-coordination, memory loss, lingering touch and sound sensations, and emotional experiences. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Alice in Wonderland syndrome」の詳細全文を読む スポンサード リンク
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