These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: The horizontal-vertical illusion: independence of line bisection and a comparison line.
    Author: McBride SA, Risser JM, Slotnick BM.
    Journal: Percept Mot Skills; 1987 Jun; 64(3 Pt 1):943-8. PubMed ID: 3601614.
    Abstract:
    Undergraduate students in social science and architecture did not differ in their accuracy of adjusting the vertical lines of L and inverted-T figures to be equal to a 1-in. horizontal line (the adjustment task) or in producing a 1 in. long line in the vertical or horizontal plane on a blank sheet of paper (the production task). In the adjustment task vertical lines were made significantly shorter than the horizontal comparison line and the shortening of the vertical line was significantly greater for the inverted-T than for the L-figure. In the production task lines drawn in the horizontal plane did not differ significantly from 1 inch but those drawn in the vertical plane were significantly shorter than 1 inch. Further, the magnitude of this error was equal to that obtained with the inverted-T figure. These results demonstrate that, while line bisection (the bisection of the horizontal by the vertical in the inverted-T figure) contributes to the horizontal-vertical illusion, the illusion clearly exists in the absence of a comparison line and can be accounted for as an overestimation of the vertical line.
    [Abstract] [Full Text] [Related] [New Search]