To see the effects of a large angle of frame-tilt, movement of the rod in the clockwise direction, and the difference between the normal and schizophrenic subjects in the perception of the upright, a mixed design (subjects × angle × presentation × trial) was used. 24 normal and 24 schizophrenic subjects were tested in a darkroom with a rod-and-frame test. The results showed a small error with a clockwise movement of the rod, when the frame also was tilted clockwise, and no difference in perception of the upright between the normal and schizophrenic subjects.
Get full access to this article
View all access options for this article.
References
1.
CohenJ.Statistical power analysis for the behavioral sciences. New York: Academic Press, 1977.
2.
EbenholtzS. M.BenzschawelT. L.The rod and frame effect and induced head tilt as a function of observation distance. Perception and Psychophysics, 1977, 22, 491–496.
3.
GuilfordJ. P.Psychometric methods. New York: McGraw-Hill, 1954.
4.
SigmanE.GoodenoughD. R.FlannaganM.Instructions, illusory self-tilt and the rod-and-frame test. Quarterly Journal of Experimental Psychology, 1979, 31, 155–165.
5.
WitkinH. A.AschS. E.Studies in space orientation: IV. Further experiments on perception of the upright with displaced visual fields. Journal of Experimental Psychology, 1948, 38, 762–782.
