2.7 Seed-Based Connectivity analysis (SCA)
The SCA analyses were performed with FSL tools with the use of identical
preprocessing and nuisance regression as for previous analyses (see
above). As for the PPI analysis, two different seed ROIs were defined by
a 2.5 mm radius sphere generated in FSL’s (Jenkinson et al., 2012)
FSLeyes, corresponding to the location (left-OFC and right-OFC) of our
previous result in the UNC neonate template space. Seed-based
connectivity maps were then generated using FSL v6.0 fMRI expert
analysis tool (FEAT) (Woolrich et al., 2001). Average time series from
the seed ROIs were extracted using the ‘fslmeants’ command and a
first-level FEAT analysis was run to assess the brain regions that had
activity correlated to the mean left-OFC and right-OFC activity
separately. The resulting z-score maps for each participant were then
normalized to UNC template space and group-level statistical analyses,
testing differences between males and females, were conducted in SPM12.
An a priori primary threshold for voxel-level statistical significance
was set to p < 0.01 and results were FDR corrected at
the cluster level (pFDR < 0.05), and a secondary threshold was
set at p < 0.05, FDR corrected at the cluster level.