Fig. 4.

A, inter-individual variation in the effect of PA-tDCS; B, repeatability of group mean response to PA-tDCS on the amplitude of MEPs evoked by PA-TMS-MEPs.

A, In all 22 individuals, MEPs evoked at each post-TDCS time point have been expressed as a fraction of baseline. The solid black line (square symbols) represents the average response from all individuals. B, mean (±SEM) amplitudes at baseline and every 10 min, post-tDCS in a group of 15 participants who were tested on 2 separate occasions (red and blue symbols and lines). The head diagrams represent coil orientation and electrode configuration used: PA-TMS-MEPs and PA-tDCS. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)