Figure 5.

Control analyses of muscle activity. (a) Relationships between pain ratings and activity in the gamma frequency band (60–90 Hz) in the spontaneous pain condition are shown for the exemplary fronto‐central EEG electrode Fz (see left panel in Figure 2b) and two EMG electrodes placed on the right masseter and neck muscles. As in previous figures, t values resulting from nonparametric cluster‐based permutation tests based on linear regressions are shown. EEG, electroencephalography, EMG, electromyography, n.s., not significant; ***p < .001. (b) Source‐level t map of the relationship between ratings during the spontaneous pain condition and data reconstructed from independent components, which were classified as artifact‐contaminated during preprocessing. Relationships based on linear regressions are shown for the gamma frequency band (60–90 Hz). As in previous figures, scaling reflects t values resulting from nonparametric cluster‐based permutation tests, positive and negative relationships are reflected by warm and cold colors, respectively, and opacity is reduced as no significant effects were found. n.s., not significant. [Color figure can be viewed at http://wileyonlinelibrary.com]