HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 97/3/2410    most recent 00778.2006v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (4) Citing Articles via Google Scholar Google Scholar Articles by Króliczak, G. Articles by Culham, J. C. Search for Related Content PubMed PubMed Citation Articles by Króliczak, G. Articles by Culham, J. C.

What Does the Brain Do When You Fake It? An fMRI Study of Pantomimed and Real Grasping

Canadian Institutes of Health Research Group in Action and Perception, Department of Psychology, University of Western Ontario, London, Canada

Submitted 28 July 2006; accepted in final form 9 January 2007

Given that studying neural bases of actions is very challenging with fMRI, numerous experiments have used pantomimed actions as a proxy to studying neural circuits of real actions. However, the underlying assumption that the same neural mechanisms mediate real and pantomimed actions has never been directly tested. Moreover, the assumption is called into question by neuropsychological evidence suggesting that real actions depend on the dorsal stream of visual processing whereas pretend actions also recruit the ventral stream. Here, we directly tested these ideas in neurologically intact subjects. Ten right-handed participants performed four tasks: 1) grasping real three-dimensional objects, 2) reaching toward the objects and touching them with the knuckle without hand preshaping, 3) pantomimed grasping in an adjacent location where no object was present, and 4) pantomimed reaching toward an adjacent location. As expected, in the anterior intraparietal area, there was significantly higher activation during real grasping than that during real reaching. However, the activation difference between pantomimed grasping and pantomimed reaching did not reach statistical significance. There was also no effect of pantomimed grasping within the ventral stream, including an object-selective area in the lateral occipital cortex. Instead, we found that pantomimed grasping was mediated by right-hemisphere activation, particularly the right parietal cortex. These results suggest that areas typically invoked by real actions may not necessarily be driven by "fake" actions. Moreover, pantomimed grasping may not tap object-related areas within the ventral stream, but rather may rely on mechanisms within the right hemisphere that are recruited by artificial and less practiced actions.

This article has been cited by other articles:

				U. Castiello and C. Begliomini The Cortical Control of Visually Guided Grasping Neuroscientist, April 1, 2008; 14(2): 157 - 170. [Abstract] [PDF]

				V. Lestou, F. E. Pollick, and Z. Kourtzi Neural substrates for action understanding at different description levels in the human brain. J. Cogn. Neurosci., February 1, 2008; 20(2): 324 - 341. [Abstract] [Full Text] [PDF]