Fig. 5

The GF-LF coordination and the center of pressure areas. The deviations of GF and LF of representative subjects with NVF for AD (a) and CN (b). The cross-correlation analysis based on the GF (c) and LF (d) rates of change. The maximal coefficient of correlation (CC) and the time shifts (TS) were used to quantify the GF and LF coupling. The coefficient of variation defined as the ratio of the standard deviation to the mean of GF of the hold phase (e). Distributions of the fingertip center of pressure and its area estimated by a fitted ellipse (f)