the brain were calculated separately for each “word” time series. The Fisher transform was used to convert the step distributed Pearson linear correlation factors into normally distributed CM coefficients. These normalized CM maps (Fig. 2D) were computed and saved in Analyze format using IDL, and loaded into SPM2 for group analyses of CM [33]. A two-way (word type × group) repeated measures ANOVA (random-effects) model with four covariates (smoking status, urine results, gender, and age) was used for group analyses of CM. Clusters with at least 15 voxels and pcorr <0.05 (corrected for multiple comparisons) were considered significant in group analysis of CM signals.
