Illusion effects on grasping are temporally constant not dynamic

J Exp Psychol Hum Percept Perform. 2005 Dec;31(6):1359-78. doi: 10.1037/0096-1523.31.6.1359.

Abstract

The authors tested whether the effects of the Ebbinghaus illusion on grasping are corrected during late phases of the movement. Surprisingly, the grasp aperture was corrected neither under no-vision (N = 52) nor under full-vision (N = 48) conditions. The authors show that previous reports of a correction (e.g., S. Glover & P. Dixon, 2002a) are due to 2 artifacts: (a) inclusion of time points at which the target object was already touched and (b) erroneous statistics. This removes the central evidence on which S. Glover and P. Dixon's (2001a) planning-control model of action is based. In addition, the authors' results can help to refine more classic notions of motor control (e.g., R. Woodworth, 1899). In consequence, the authors reject S. Glover and P. Dixon's (2001a) planning-control model but not classic online-control theories.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Female
  • Hand Strength*
  • Humans
  • Male
  • Middle Aged
  • Optical Illusions*
  • Time Factors