Fig. 4.

Connections for which coupling parameters during right hand grip become less inhibitory/more facilitatory with age. Values are given as r2 (all p < 0.05, except for right M1 to right SMA p < 0.0507) and are extracted from the A matrix (n = 27). Asterisk indicates DCM values of the A matrix that were all positive (with the exception of 1–3 subjects) and became more positive with age. Note that the correlation value for between left M1 and right M1 is different than the one of Fig. 3 because it includes data from a larger number of subjects.