2.5 fMRI data acquisition and analysis
Details regarding blood-oxygen-level-dependent (BOLD) imaging fMRI data acquisition, preprocessing, quality assurance, and first-level analyses are provided in the Supplemental Methods.
2.5.1 Second-level analysis: Group-level random effects analysis was performed in SPM8 to examine within-subjects differential activation patterns based on instruction, using one-sample t -tests. First, to identify regions modulated by meditation emotion regulation techniques vs. a control condition, we examined the contrasts BREATH vs. LOOK and ACCEPT vs. LOOK. To identify regions modulated by the non-meditation emotion regulation condition, we examined DISTRACT vs. LOOK. Then, we compared the two meditation conditions (BREATH vs. ACCEPT) and compared the meditation vs. non-meditation instructions (i.e., BREATH vs. DISTRACT, ACCEPT vs. DISTRACT).
2.6.2 DMN regions of interest (ROI) analyses: To identify the effects of different emotion regulation techniques on brain activity, we focused on a priori ROIs in the DMN: MFC, posterior cingulate cortex, dorsal frontal cortex, and supplementary motor area. Small-volume familywise error (FWE) correction was used to identify significant ROI results (pFWE ≤ 0.05 and 5-voxel minimum).
2.6.3 Whole brain analyses: A complementary whole-brain analysis was performed using a whole-brain FWE corrected threshold (pFWE< 0.05). See supporting Information for details.