Figure 2.

Correlation circle created with the first two components of the principal component analysis (PCA) (left column) and corresponding correlation matrices (right column) in the dominant hemisphere of (A) healthy subjects and (B) in the unaffected and (C) affected hemisphere of stroke patients. On PCA graphs are plotted the seven electrophysiological variables on a plane spanned by PC1 and PC2. In the correlation matrices are presented the spearman correlation coefficients with their 95% Confidence Interval. X_int, X intercept; IO140, Motor Evoked Potential amplitude recorded at 140% rMT; MEP_max, maximum value of the sigmoid function; PS, peak slope; AUC, area under the input output curve, m, slope; S₅₀, stimulus intensity needed to obtain 50% of the maximum response. *** <0.001, ** <0.01, * <0.05, NS, non-significant.