Motor learning transiently changes cortical somatotopy


Learning a complex motor skill is associated with changes in motor cortex representations of trained body parts. It has been suggested that representation changes reflect the storage of a skill, i.e., the motor memory trace. If a reflection of the trace, such modifications should persist after training is stopped for as long as the skill is retained. The objective here was to test the persistence of learning-related changes in the representation of the forelimb of the rat after learning a reaching task using repeated epidural stimulation mapping of primary motor cortex. It is shown that the forelimb representations enlarge after 8 days of training (n=8) but contract while performing arm movements without learning (n=7, p=0.006); hindlimb representations remain unchanged. Enlargement correlated with learning success (r=0.82; p=0.012). Subsequently, after 8 days without training, representation size reverted to baseline while the motor skill was retained. Somatotopy remained unaltered by a second training phase in which performance did not improve further (n=5). These findings suggest that successful acquisition but not storage of a motor skill depends on cortical map changes. The motor memory trace in rats may require changes in motor cortex organization other than those detected by stimulation mapping.

DOI: 10.1016/j.neuroimage.2007.11.018

4 Figures and Tables

Citations per Year

122 Citations

Semantic Scholar estimates that this publication has 122 citations based on the available data.

See our FAQ for additional information.

Cite this paper

@article{MolinaLuna2008MotorLT, title={Motor learning transiently changes cortical somatotopy}, author={Katiuska Molina-Luna and Benjamin Hertler and Manuel M. Buitrago and Andreas R. Luft}, journal={NeuroImage}, year={2008}, volume={40 4}, pages={1748-54} }