Skip to main content

Research Repository

Advanced Search

FMRI Reveals a Dissociation between Grasping and Perceiving the Size of Real 3D Objects

Cavina-Pratesi, C.; Goodale, M.A.; Culham, J.C.

FMRI Reveals a Dissociation between Grasping and Perceiving the Size of Real 3D Objects Thumbnail


Authors

C. Cavina-Pratesi

M.A. Goodale

J.C. Culham



Abstract

Background Almost 15 years after its formulation, evidence for the neuro-functional dissociation between a dorsal action stream and a ventral perception stream in the human cerebral cortex is still based largely on neuropsychological case studies. To date, there is no unequivocal evidence for separate visual computations of object features for performance of goal-directed actions versus perceptual tasks in the neurologically intact human brain. We used functional magnetic resonance imaging to test explicitly whether or not brain areas mediating size computation for grasping are distinct from those mediating size computation for perception. Methodology/Principal Findings Subjects were presented with the same real graspable 3D objects and were required to perform a number of different tasks: grasping, reaching, size discrimination, pattern discrimination or passive viewing. As in prior studies, the anterior intraparietal area (AIP) in the dorsal stream was more active during grasping, when object size was relevant for planning the grasp, than during reaching, when object properties were irrelevant for movement planning (grasping>reaching). Activity in AIP showed no modulation, however, when size was computed in the context of a purely perceptual task (size = pattern discrimination). Conversely, the lateral occipital (LO) cortex in the ventral stream was modulated when size was computed for perception (size>pattern discrimination) but not for action (grasping = reaching). Conclusions/Significance While areas in both the dorsal and ventral streams responded to the simple presentation of 3D objects (passive viewing), these areas were differentially activated depending on whether the task was grasping or perceptual discrimination, respectively. The demonstration of dual coding of an object for the purposes of action on the one hand and perception on the other in the same healthy brains offers a substantial contribution to the current debate about the nature of the neural coding that takes place in the dorsal and ventral streams.

Citation

Cavina-Pratesi, C., Goodale, M., & Culham, J. (2007). FMRI Reveals a Dissociation between Grasping and Perceiving the Size of Real 3D Objects. PLoS ONE, 2(5), https://doi.org/10.1371/journal.pone.0000424

Journal Article Type Article
Publication Date May 1, 2007
Deposit Date Jan 24, 2012
Publicly Available Date Mar 29, 2024
Journal PLoS ONE
Publisher Public Library of Science
Peer Reviewed Peer Reviewed
Volume 2
Issue 5
DOI https://doi.org/10.1371/journal.pone.0000424

Files

Published Journal Article (836 Kb)
PDF

Publisher Licence URL
http://creativecommons.org/licenses/by/4.0/

Copyright Statement
Copyright: © 2007 Cavina-Pratesi et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.





You might also like



Downloadable Citations