The general linear model (GLM) of SPM8 (http://www.fil.ion.ucl.ac.uk/spm) was used to conduct fMRI data analyses. Linear contrasts employing canonical hemodynamic response functions were used to estimate differential effects of condition from the contrast of Faces > Shapes for each individual. Individual contrast images were then used in second-level random effects models accounting for scan-to-scan and participant-to-participant variability to determine mean condition-specific regional responses using one-sample t-tests. Regions of interest (ROIs) masks for the bilateral amygdala were constructed using the automatic anatomical labeling (AAL) within WFU PickAtlas Tool, version 1.04. A statistical threshold of p < 0.05, FWE corrected, and ≥10 contiguous voxels was applied to amygdala analyses within each hemisphere. BOLD values from voxels within the amygdala exhibiting strongest main effect of task were extracted using the VOI tool in SPM8.
