Table 2. Parameters (Par.) of fitted bivariate normal distributions for older participants.

Par.	Self-paced Movement				Externally-paced Movement
	TA		MG		TA		MG
	Left	Right	Left	Right	Left	Right	Left	Right
n	6	5	5	6	9	5	5	2
RMSD	0.965 ± 0.794	1.29 ± 0.55	0.843 ± 0.636	1.18 ± 0.46	1.60 ± 1.47	1.37 ± 0.81	1.36 ± 1.24	0.757 ± 0.763
COD	0.758 ± 0.151	0.732 ± 0.117	0.703 ± 0.158	0.741 ± 0.142	0.666 ± 0.139	0.719 ± 0.117	0.751 ± 0.074	0.858 ± 0.044
A	8.53 ± 8.92	8.77 ± 6.42	5.95 ± 5.79	7.88 ± 4.78	8.65 ± 7.23	8.07 ± 6.53	7.41 ± 5.89	5.72 ± 5.27
σRC	1.07 ± 0.33	1.33 ± 0.22	1.31 ± 0.23	1.38 ± 0.25	1.32 ± 0.36	1.25 ± 0.27	1.19 ± 0.17	1.15 ± 0.21
σML	1.44 ± 0.49	1.52 ± 0.29	1.83 ± 0.54	1.55 ± 0.46	1.51 ± 0.63	1.77 ± 0.62	2.18 ± 0.74	1.56 ± 0.20
μRC	0.498 ± 0.791	0.587 ± 0.363	0.622 ± 0.541	0.506 ± 0.284	0.183 ± 0.671	0.468 ± 0.190	0.685 ± 0.357	0.736 ± 0.071
μML	0.151 ± 0.603	0.122 ± 0.355	0.0489 ± 0.6677	0.0531 ± 0.3943	-0.0552 ± 0.4156	0.743 ± 0.529	0.0115 ± 0.8911	0.0283 ± 0.590

Each entry is the mean ± standard deviation for n cortical distributions of coherence between EEG signals and EMG signals from tibialis anterior (TA) and medial gastrocnemius (MG) muscles. RMSD stands for root-mean-square deviation, and COD stands for coefficient of determination. A, σ, and μ are respectively the peak value, standard deviation, and mean of the fitted bivariate normal distributions. A is measured in Hz multiplied by the percentage of movement cycle. The mean is located on the rostrocaudal-mediolateral (μ_RC, μ_ML) coordinate system, where (0,0) indicates C_z. A displacement by one on the coordinate system corresponds to a displacement by one electrode location in the rostrocaudal or mediolateral direction. Positive rostrocaudal and mediolateral coordinates respectively indicate anterior and left.