macropsia


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macropsia

 [mah-krop´se-ah]
an illusion in which objects appear larger than their actual size.

ma·crop·si·a

(mă-krop'sē-ă),
Perception of objects as larger than they are.
[macro- + G. opsis, vision]

macropsia

A disorder of visual perception (dysmetropsia) in which objects in the visual field appear larger than normal, some forms of which have been fancifully termed the “Alice in Wonderland” syndrome. Retinal macropsia is attributed to compression of receptor spacing, resulting in greater stimulation and a larger perceived image.

Aetiology
Aniseikonia, prescription drugs (e.g., citalopram, zolpidem), illicit drugs (e.g., LSD, psilocybin, marijuana), migraines, epilepsy, hypolycaemia, EBV virus infection, prions.

macropsia

Abnormal perception of the size of objects so that they seem larger than they actually are.

macropsia

Anomaly of visual perception in which objects appear larger than they actually are. It may occur as a result of abnormal accommodation (less than required for the fixation distance) or because of various retinal anomalies in which the visual receptors are crowded together, or because of the recent wear of either base-in prisms or a presbyopic correction, etc. Syn. megalopsia. See dysmegalopsia; micropsia; meta-morphopsia.
References in periodicals archive ?
A study conducted on 3224 Japanese adolescents, aged 13 to 18 years, demonstrated that the occurrence of micropsia and macropsia was 6.5% in boys and 7.3% in girls, suggesting that the visual illusions of AIWS may be not so rare in general population [10].
In this view, type B AIWS symptoms, such as micropsia and macropsia, should be largely but not only ascribed to the temporal lobe.
Weidenfeld and Borusiak [45] mentioned a 7-year-old boy who, 3 years after episodes of micropsia, macropsia, and pelopsia, developed a tension type headache.
Zolpidem-induced macropsia in anorexic woman (letter).
The authors found that certain phenomena--such as increased intensity of colors, increased vividness of objects, macropsia, micropsia, and transient paranoia--were specific to the cocaine-induced psychotic state.
The early symptoms of macular disease include metamorphopsia (distortion of vision), micropsia, macropsia, and delayed recovery after exposure to bright lights (so that the headlights of oncoming cars may make night driving very difficult).
The clinical manifestation of an ERM can be completely asymptomatic or profoundly symptomatic with metamorphopsia, micropsia or macropsia, decreased visual acuity (VA), and loss of central vision.
Los mas caracteristicos son los que afectan a la percepcion visual, principalmente a la forma, tamano y situacion espacial de los objetos (metam orfopsia, macropsia, micropsia y teleopsia); macro y microsomatognosia si se refieren a la imagen corporal.
Common visual disturbances attributed to HPPD are recurrent geometric hallucinations, perception of peripheral movement, colored flashes, intensified colors, palinopsia, positive afterimages, haloes around objects, macropsia, and micropsia occurring spontaneously in individuals with no prior psychopathology.