Document Detail


Analysis and explanation of the Thiéry-Wundt illusion.
MedLine Citation:
PMID:  20842971     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The midpoint of the axis of bisection in a triangle appears to be displaced toward the apex so that the apical extent seems to be shorter than the basal extent, an effect originally reported in 1895 by Thiéry and later in 1898 by Wundt and, therefore, referred to here as the Thiéry-Wundt illusion. Following a demonstration strongly suggesting that the illusion is yet another version of the Müller-Lyer effect in a stimulus figure with inward-directed angles, four exploratory experiments designed to throw more light on this group of illusions are reported. The first showed that the effect occurs in an open angle, between converging lines that do not meet to form an apex, between converging stepped lines, and when one of the converging lines is removed, leaving a single oblique line. The other three experiments showed that the illusion also occurs in an open semicircle and a rectangular bracket, is weakened by the addition of a complete or partial baseline to form a triangle, and weakly but reliably when the angle is minimally formed from dots marking the ends of oblique lines. On the basis of these data, Judd's version of the conventional Müller-Lyer figure, and informal but easily repeatable observations, it is concluded that the Thiéry-Wundt illusion is, like other variants of the Müller-Lyer group of illusions, due to a process of directional biasing-an extension of the concept of biasing proposed originally by Morgan et al (1990, Vision Research 30 1793 1810).
Authors:
Ross H Day; Andrew C Kimm
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Perception     Volume:  39     ISSN:  0301-0066     ISO Abbreviation:  Perception     Publication Date:  2010  
Date Detail:
Created Date:  2010-09-16     Completed Date:  2010-12-16     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  0372307     Medline TA:  Perception     Country:  England    
Other Details:
Languages:  eng     Pagination:  942-52     Citation Subset:  IM    
Affiliation:
School of Psychological Science, La Trobe University, Melbourne, Victoria 3086, Australia. r.day@latrobe.edu.au
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Discrimination Learning / physiology*
Humans
Models, Theoretical
Optical Illusions / physiology*
Pattern Recognition, Visual / physiology*
Photic Stimulation / methods

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Common neural mechanisms for the evaluation of facial trustworthiness and emotional expressions as r...
Next Document:  The role of visual experience in mental scanning of actual pathways: evidence from blind and sighted...