Hand posture effects on handedness recognition as revealed by the Simon effect

• Published in: Frontiers in human neuroscience Vol. 3; p. 59
• Main Author: Lameira, Allan
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Research Foundation 30.11.2009; Frontiers Media S.A
• Subjects: Biomechanics; Emulation; Hand; hand posture; Handedness; handedness recognition; Hands; Influence; Medical research; Motor Imagery; Neuroscience; Posture; Simon effect; Transcranial magnetic stimulation; Brazil; Rio de Janeiro Brazil; motor imagery; handedness recognition; Simon effect; hand posture
• ISSN: 1662-5161; 1662-5161
• DOI: 10.3389/neuro.09.059.2009

We investigated the influence of hand posture in handedness recognition, while varying the spatial correspondence between stimulus and response in a modified Simon task. Drawings of the left and right hands were displayed either in a back or palm view while participants discriminated stimulus handedness by pressing either a left or right key with their hands resting either in a prone or supine posture. As a control, subjects performed a regular Simon task using simple geometric shapes as stimuli. Results showed that when hands were in a prone posture, the spatially corresponding trials (i.e., stimulus and response located on the same side) were faster than the non-corresponding trials (i.e., stimulus and response on opposite sides). In contrast, for the supine posture, there was no difference between corresponding and non-corresponding trials. Control experiments with the regular Simon task showed that the posture of the responding hand had no influence on performance. When the stimulus is the drawing of a hand, however, the posture of the responding hand affects the spatial correspondence effect because response location is coded based on multiple reference points, including the body of the hand.