Induced vestibular stimulation and the moon illusion.

Abstract

Vestibular stimulation was induced by having 5 travel on a 3.8-sec. parallel swing. Two luminous disks were affixed to the swing in S's median and horizontal plane and two at angles of 40° and 80°, respectively. The diameter of one horizontal stimulus was changed in ascending and descending fashion. Each standard stimulus was presented individually for 3 sec. in a standing-still position. The swing release terminated the standard stimulus and activated the comparison stimulus for .2 sec. when S had reached his return point or when he had traveled three-quarters of the complete swing. Three 5s made "bigger" and "smaller" responses with the nondominant eye covered. The results of an analysis of variance showed significant differences between the 0°, 40°, and 80° conditions (p < .01) and a significant interaction between these conditions and 5s (p < .01). Induced vestibular activity was not significant. Eye movement (40° condition), however, did have a significant effect.

More things in heaven and earth: A reply to Loftus.

“…2Perhaps including the history of near-misses. The mere fact of elevation, not elevation of gaze (Holway & Boring, 1940) or stimulation of the vestibular apparatus as the head is raised (Van Eyl, 1972), underlies the moon illusion.…”