Congruency effects in the single-trial Stroop tasks.

<p>This Figure shows confidence intervals (p = .05) of the Congruency effects (as the respective differences in performance parameters between incongruent minus congruent conditions) from Colour- (left) and Counting-Stroop (right). Reaction-times were significantly slower in incongruent trials of both Stroop-Tests in all four groups (as the respective confidence intervals indicated by vertical bars around the respective mean do not include zero), and did not reveal any group-differences (as no mean lie outside the confidence intervals of comparison, see line A, above). Accuracy was significantly lower in incongruent trials of the Counting Stroop similarly for all groups (different from zero and negative in all groups, and all confidence intervals overlap with the respective means), but in the Colour Stroop interference liability on accuracy was present only in the pure ADHD and CTD groups, while Controls and children with ADHD+TIC did not show reduced accuracy in incongruent trials and showed less congruency effect as compared to both other groups (line B). The combined Speed-Accuracy parameter (line C, mean difference incongruent minus congruent trials of z-standardized reaction-time and accuracy scores) showed in the Colour Stroop (left) elevated interference load in the pure ADHD and pure CTD groups than in the controls and comorbid ADHD+TIC groups only, but no significant group differences in the Counting-Stroop (right).