The group mean of the inter-keystroke interval (IKI) while playing a practiced tone sequence as fast and accurately as possible over four successive days of the sessions for the trained group (filled circle) and control group (open circle). An error bar indicates the standard error. ***: p < 0.001. (Subsets) a tone sequence used for the current practice and learning test. The numbers indicate fingering (2 to 5 correspond to index to little finger).
Furuya et al. BMC Neuroscience 2013 14:133 doi:10.1186/1471-2202-14-133