floating-finger illusion

Quick Reference

A visual illusion that is seen when the forefingers of each hand are held horizontally about 30 centimetres in front of the eyes, with the fingertips touching and the gaze focused on a point in the distance, and the fingertips are then drawn apart about one centimetre. A disembodied finger, with two tips, appears floating in mid-air, and it can be lengthened or shortened by varying the distance between the fingertips (see illustration). The illusion was discovered in 1928 and described in the journal Psychological Review by the US psychologist Winford Lee Sharp (1890–1975).

Floating-finger illusion

Subjects: Psychology.

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