Identification of cortical activation and white matter architecture according to short-term motor learning in the human brain: functional MRI and diffusion tensor tractography study.

Objectives: The purpose of this study was to examine whether two weeks of short-term motor training led to changes of cortical activation patterns and white matter integrity in cortical and subcortical structures according to motor skill acquisition, using functional MRI (fMRI) and diffusion tensor image (DTI).

Methods: We enrolled twenty healthy volunteers, who were randomly assigned to training and control groups. The training group was trained with a serial reaction time (SRT) task, one hour a day for 10 days within two weeks, whereas the control group had no training. Movement accuracy (MA) and movement time (MT) were tested twice before and after training, while fMRI was scanned during SRT task. Immediately after these tests, DTI was conducted.

Results: The training group showed significant differences in the increase of MA and the reduction of MT, compared with control group. The activated volume of cortices related to motor function was gradually decreased in the training group, according to motor skill acquisition. DTI analysis showed no significant differences between pre- and post-tests in both groups.

Conclusions: Our findings indicated that short-term motor training led to cortical activation patterns of the cerebral cortex according to implicit motor learning. However, changes of white matter integrity were not observed. It seems that short-term motor training may not be enough to change white matter architectures, due to lack of the training period.