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an illusion in which objects appear larger than their actual size.
Perception of objects as larger than they are.
[macro- + G. opsis, vision]
macropsiaA 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.
Aniseikonia, prescription drugs (e.g., citalopram, zolpidem), illicit drugs (e.g., LSD, psilocybin, marijuana), migraines, epilepsy, hypolycaemia, EBV virus infection, prions.
macropsiaAbnormal perception of the size of objects so that they seem larger than they actually are.
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.