Prabhu, G.;
Lemon, R.;
Haggard, P.;
(2007)
On-line control of grasping actions: object-specific motor facilitation requires sustained visual input.
Journal of Neuroscience
, 27
(46)
pp. 12651-12654.
10.1523/JNEUROSCI.4308-07.2007.
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Abstract
Dorsal stream visual processing is generally considered to underlie visually driven action, but when subjects grasp an object from memory, as visual information is not available, ventral stream characteristics emerge. In this study we use paired-pulse transcranial magnetic stimulation (TMS) to investigate the importance of the current visual input during visuomotor grasp. Previously, the amplitude of the paired-pulse motor evoked potentials (MEPs) in hand muscles before movement onset have been shown to predict the subsequent pattern of muscle activity during grasp. Specific facilitation of paired-pulse MEPs may reflect premotor–motor (PMC–M1) cortex connectivity. Here we investigate the paired-pulse MEPs evoked under memory-cued and visually driven conditions before grasping one of two possible target objects (a handle or a disc). All trials began with a delay period of 1200 ms. Then, a TMS pulse served as the cue to reach, grasp and hold the target object for 0.5 s. Total trial length was 5 s. Both objects were continually visible in both conditions, but the way in which the target object was designated differed between conditions. In the memory-cued condition, the target object was illuminated for the first 200 ms of the trial only. In the visually driven condition, the target object was illuminated throughout the 5 s trial. Thus, the conditions differed in whether or not the object to be grasped was designated at the time of movement initiation. We found that the pattern of paired-pulse MEP facilitation matched the pattern of object-specific muscle activity only for the visually driven condition. The results suggest that PMC–M1 connectivity contributes to action selection only when immediate sensory information specifies which action to make.
| Type: | Article |
|---|---|
| Title: | On-line control of grasping actions: object-specific motor facilitation requires sustained visual input |
| Open access status: | An open access version is available from UCL Discovery |
| DOI: | 10.1523/JNEUROSCI.4308-07.2007 |
| Publisher version: | http://dx.doi.org/10.1523/JNEUROSCI.4308-07.2007 |
| Language: | English |
| Additional information: | Published by the Society of Neuroscience. Article reproduced here for non-commercial purposes under the terms of the Creative Commons Attribution-Noncommercial-Share Alike 3.0 Unported license. For further information see: http://creativecommons.org/licenses/by-nc-sa/3.0/ This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License. The license allows you to copy, distribute, and transmit the work, as well as adapting it. However, you must attribute the work to the author (but not in any way that suggests that they endorse you or your use of the work), and cannot use the work for commercial purposes without prior permission of the author. If you alter or build upon this work, you can distribute the resulting work only under the same or similar license to this one. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-sa/3.0/ or send a letter to Creative Commons, 444 Castro Street, Suite 900, Mountain View, California, 94041, USA. |
| Keywords: | Transcranial magnetic stimulation, corticospinal, motor cortex, dorsal visual stream, grasping, affordance |
| UCL classification: | UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Brain Sciences > Div of Psychology and Lang Sciences > Institute of Cognitive Neuroscience UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Brain Sciences > UCL Queen Square Institute of Neurology > Department of Neuromuscular Diseases |
| URI: | https://discovery-pp.ucl.ac.uk/id/eprint/5860 |
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