Nature Neuroscience
6, 421 - 427 (2003)
Published online: 17 March 2003; | doi:10.1038/nn1031
Graspable objects grab attention when the potential for action is recognizedTodd C. Handy1, 2, Scott T. Grafton1, 2, 3, Neha M. Shroff1, 2, Sarah Ketay1, 2
& Michael S. Gazzaniga1, 21
Center for Cognitive Neuroscience, 6162 Moore Hall, Dartmouth College, Hanover, New Hampshire 03755, USA
2
Department of Psychological and Brain Sciences, 6162 Moore Hall, Dartmouth College, Hanover, New Hampshire 03755, USA
3
Dartmouth Brain Imaging Center, 6162 Moore Hall, Dartmouth College, Hanover, New Hampshire 03755, USA
Correspondence should be addressed to Todd C. Handy todd.c.handy@dartmouth.eduVisually guided grasping movements require a rapid transformation of visual representations into object-specific motor programs. Here we report that graspable objects may facilitate these visuomotor transformations by automatically grabbing visual spatial attention. Human subjects viewed two task-irrelevant objectsone was a 'tool', the other a 'non-tool'while waiting for a target to be presented in one of the two object locations. Using event-related potentials (ERPs), we found that spatial attention was systematically drawn to tools in the right and lower visual fields, the hemifields that are dominant for visuomotor processing. Using event-related fMRI, we confirmed that tools grabbed spatial attention only when they also activated dorsal regions of premotor and prefrontal cortices, regions associated with visually guided actions and their planning. Although it is widely accepted that visual sensory gain aids perception, our results suggest that it may also have consequences for object-directed actions.
|