Recurrence Quantification Analysis of F-Waves and the Evaluation of Neuropathies

Figure 1

Recurrence plots of 15 ms time periods isolated from 150 ms recordings following nerve stimulation. F-waves were either absent (a) or present (b), but with different profiles when present. The recurrence plots show detailed distributions of recurrent points (blue areas) falling beneath an absolute radius threshold, namely, a predetermined threshold below which the point could be considered recurrent. Points making up the F-wave falling outside of the radius did not score recurrent points. The and axes represent time. As such for a particular point in time on the -axis, a blue point on the -axis (i.e., vertically above that time on the -axis) would indicate recurrence points at subsequent times in the recordings.

(a)

(b)