Visually 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 objects--one 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.
Pubmed ID: 12640459 RIS Download
Mesh terms: Attention | Brain Mapping | Evoked Potentials | Feedback | Frontal Lobe | Functional Laterality | Hand | Hand Strength | Humans | Magnetic Resonance Imaging | Motor Cortex | Movement | Neuropsychological Tests | Prefrontal Cortex | Psychomotor Performance | Visual Cortex | Visual Fields | Visual Pathways | Visual Perception
Publication data is provided by the National Library of Medicine ® and PubMed ®. Data is retrieved from PubMed ® on a weekly schedule. For terms and conditions see the National Library of Medicine Terms and Conditions.