Figure 5.
Periodograms of super-responders and poor/intermediate responders diverge over time and stimulation of super-responders is less phase-locked to long episodes. (A) We found that most patients received stimulation between the rising phase and peak phase of daily detections. Seizure reduction did not significantly correlate with phase angle of long episodes on the circadian cycle (circular-linear correlation; P = 0.91). (B) For peak multidien rhythms, long episodes occurred between the rising and peak phase of the most prominent multidien rhythm (≥48 h). Seizure reduction did not significantly correlate with phase angle of long episodes on the circadian cycle (circular-linear correlation; P = 0.90). (C) Periodograms are not significantly different at the start of stimulation therapy between super-responders and intermediate/poor responders. (D) In the last 90 days of stimulation, super-responders experienced increased power in short periods (≤24 h) (two-sample t-test, P = 1.55 × 10−3) while intermediate/poor responders had increased power in multidien periodics (≥48 h) (two-sample t-test, P = 1.73 × 10−3). (E) Across all periods from 3 h to 45 days, there was a high level of phase-locking between long episodes and stimulation episodes in intermediate and poor responders. However, the distribution of stimulation episodes and long episodes between super-responders and both intermediate (two-sample Kuiper test; P < 0.01) and poor responders (two-sample Kuiper test; P < 0.01) were significantly different, indicating more stimulation occurred outside of high-risk long episodes in super-responders. Von mises distributions for super-responders (µ: −1.39 rad, κ = 0.74), for intermediate responders (µ: −0.36 rad, κ = 1.06) and for poor responders (µ: −0.36 rad, κ = 1.15).