Brain Activations to Dyspnea in Patients With COPD

Figures

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  FIGURE 1. (A) Mean (±SD) ratings of occlusion intensity and unpleasantness for COPD patients and control subjects. (B) Averaged waveforms (μV) of the respiratory-related evoked potential for COPD patients and control subjects from sensors at frontal (Nf), centro-lateral (N1 & P2), and centro-parietal (P1 & P3) scalp positions. Based on previous reports (von Leupoldt et al., 2011), RREP components were identified as: Nf, negative peak – frontal region (latency: 25–50 ms); P1, positive peak – centro-parietal region (latency: 45–65 ms); N1, negative peak – centro-lateral region (latency: 85–125 ms); P2, positive peak – central region (latency: 160–230 ms); P3, positive peak – centro-parietal region (latency: 250–350 ms). RREP components and respective topographical areas are indicated on the figure. (C) Mean (±SD) amplitudes (μV) for RREP components Nf, P1, N1, P2, and P3 for COPD patients and control subjects. Mean amplitudes were calculated around each individual peak using a latency window of ±10 ms for Nf and P1, and ±20 ms for N1, P2, and P3. (D) Correlations between mean P3 amplitudes (μV) and Borg scale ratings of intensity and unpleasantness for COPD patients. ∗p < 0.05; ∗∗∗p < 0.001.