Within-Session Increase in Total Alpha Power.
A) Within-Session Increase in Binned Total Alpha Power. The group average of binned alpha power is fitted to a linear (black), quadratic (green), and exponential (orange) model. Blue Trace: Average alpha power (7–14 Hz, mean and standard error (S.E.), n = 12 subjects) from the hand area in SI across the experiment that has been divided into bins of 50 trials. For each subject, alpha power was normalized to the earliest bin average. No significant improvement beyond linear model is seen. (Linear fit: R2 = 0.81, p = 0.03, one-sided t-test) B) Within-Session Increase in Expression of Total Alpha Power. Blue Trace: Average alpha power (7–14 Hz, mean and S.E., n = 12 subjects) from the hand area in SI across three blocks of the experiment (early (E), middle (M), and late (L) trials). For each subject, alpha power was normalized to the early block (E) average. Linear regression analysis (orange dash) confirmed a statistically significant increase in total alpha power across the experimental session (R2 = 0.99, p<0.01, one-sided t-test).
