Abstract
Four experiments on apparent misalignment of oblique collinear bars are reported. The data from the first three experiments showed that the misalignment was slight but significant when no direction other than that of the bars themselves was delineated and about double when the vertical was delineated by movements of the adjustable bar. When the vertical was delineated by both these movements and the ends of the bars (or by vertical parallel lines), the misalignment was more than six times greater. Conversely, it was reduced when the bar ends delineated the vertical and bar movements delineated the direction at right angles to the bars. The data from a fourth experiment showed that the inner pair of edges were closely involved in apparent misalignment and that the outer ends were not. The relationship between the misalignment effect with bars and the Poggendorif figure (oblique lines separated by parallels), the delineation of direction by edges and movement, and the implications of these data for an explanation are discussed.
Article PDF
Similar content being viewed by others
References
Avery, G. C., &Day, R. H. (1969). Basis of the horizontal-vertical illusion.Journal of Experimental Psychology,81, 376–380.
Avery, G. C., &Day, R. H. (1971). Relationship between the horizontal-vertical illusions for velocity and extent.Journal of Experimental Psychology,89, 22–31.
Cornsweet, T. N. (1962). The staircase method in psychophysics.American Journal of Psychology,75, 485–491.
Day, R. H. (1973). The oblique line illusion: The Poggendorff effect without parallels.Quarterly Journal of Experimental Psychology,25, 535–541.
Day, R. H. (1989). Natural and artificial cues, perceptual compromise and the basis of veridical and illusory perception. In D. Vickers & P. L. Smith (Eds.),Human infonnation processing: Measures, mechanisms and models. London: Elsivier.
Day, R. H., &Stecher, E. J. (1992). Some variant forms of the Poggendorff illusion and their implications for an explanation.Bulletin of the Psychonomic Society,30, 26–28.
Künnapas, T. M. (1955). An analysis of the “vertical-horizontal illusion.”Journal of Experimental Psychology,49, 134–140.
Künnapas, T. M. (1957). The vertical-horizontal illusion and the visual field.Journal of Experimental Psychology,53, 405–407.
Mosi, T. (1981). Reduction of the Poggendorif effect by the motion of oblique lines.Perception & Psychophysics,29, 15–20.
Weintraub, D. J., Krantz, D. H., &Olson, T. P. (1980). The Poggendorff illusion: Consider all the angles.Journal of Experimental Psychology: Human Perception & Performance,6, 718–725.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Day, R.H., Stecher, E.J. & Parker, A.L. The effect of edge orientation and movement direction on the apparent misalignment of collinear bars. Perception & Psychophysics 53, 642–647 (1993). https://doi.org/10.3758/BF03211740
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.3758/BF03211740