Fig. 2. Behavioral data for the video game Tetris® measured as score per minute.
Changes in task performance differed between the two PET/MRI measurements (M1 and M2), groups and task conditions (group*time*condition interaction, p < 10−5). a For the easy task condition, the training group (n = 21) showed a 2.7-fold increase in performance, which was significantly higher compared to the control group (n = 20). b For the hard task, changes in performance followed a similar pattern but effects were more pronounced, with the training group showing a 3.1-fold improvement in performance. Also, task performance for the hard task condition further increased even without training until the final visit (FV). The time between measurements/visits was 4 weeks. Initial performance at measurement 1 was not significantly different between the groups for both task conditions (p > 0.5). c Monitoring the task performance during the training period highlights the continuous improvement. The learning curve further matched with the performance of the two PET/MRI measurements as indicated by the dots (average values of M1 and M2 in b). Solid and dotted lines represent mean and standard deviation, respectively. Data were cut after 21 days as less than 1/3 of the subjects trained longer than this period. For a and b, post-hoc comparisons indicate significant differences for the group*time interactions (#p < 0.05, ####p < 10−9), for the differences between the two measurements (**p < 0.01, ***p < 0.001, ****p < 10−10) and for the difference between measurement 2 and the final visit (♦p < 0.05). All p-values were corrected for multiple comparisons with the Bonferroni-Holm procedure. Boxplots indicate median values (center line), upper and lower quartiles (box limits) and 1.5× interquartile range (whiskers). Data for the plots are provided in Supplementary Data 1–3.