Table 2.
Regression analysis for baseline rs-fMRI comparison between the CWP group and the HC group on the covariates PTT as a measure of pain sensitivity, and the construct psychological strain
| Covariate | Seed-ROI | Target-ROI | t-value (df=70) | R2 | Effect size (Cohen’s ƒ2) | p-value |
|---|---|---|---|---|---|---|
| Baseline resting state | ||||||
| PTT | SN RAIC | DMN LPC | 3.31 | 0.15 | 0.176 | 0.026 |
| SN RAIC | SN LAIC | 2.92 | 0.10 | 0.111 | 0.043 | |
| SN LAIC | SN RAIC | 2.92 | n.s. | 0.085 | ||
| DMN PCC | n.s. | >0.1 | ||||
| Psychological strain | n.s. | >0.1 | ||||
| Post-pain versus baseline resting state | ||||||
| PTT | n.s. | >0.1 | ||||
| Psychological strain | n.s. | >0.1 | ||||
Notes: The p-value is FDR -corrected for seven targets, subsequently Bonferroni-corrected for three seeds. Target ROIs and t-values of results with p-value below 0.1 are shown.
Abbreviations: rs-fMRI, resting state functional magnetic resonance imaging; CWP, chronic widespread pain; HC, healthy control; PTT, pain tolerance threshold; ROI, region of interest; df, degrees of freedom; SN, salience network; RAIC, right anterior insular cortex; LAIC, left anterior insular cortex; DMN, default mode network; LPC, lateral parietal cortex; PCC, posterior cingulate cortex; n.s., not significant.