Changes of Spontaneous Oscillatory Activity to Tonic Heat Pain
Figure 4
Time-varying normalized power spectra among four stimulation conditions.
Grand averaged time frequency distributions of the spectral power density difference (left panel, D–B, D–C) were measured on contralateral central electrodes (C2, C4, CP2, and CP4), and power differences (right panel, D–A) were measured at frontal central (Fz, FC1, FC2, and Cz) and ipsilateral central (C1, C3, CP1, and CP3) electrodes. The dashed lines represent the start of each min, and the alpha suppression and gamma enhancement were marked in white rectangle on the time-frequency distribution of spectral power difference. Grand averaged time-varying spectral power curve at contralateral central electrodes within alpha (10–15 Hz) frequency band (left panel), and at frontal and ipsilateral central electrodes (right panel) within gamma (30–100 Hz) frequency band were also displayed in yellow, green, blue, and red for conditions A, B, C, and D. The intervals with significance difference across the conditions were marked in grey.