Fig 1.
Sequence and duration of signals in an Attention Network Test trial.
Arrow: time axis with signal duration (ms); black cross: fixation point; red star: cue signal; central yellow fish: target signal; lateral pairs of yellow fishes: flanks.
Fig 2.
Grand ANT-related potentials averaged across subjects, of all cue and target conditions.
Twenty EEG channels in the control (blue) and ADHD (black) groups (scales in the lower right corner, where the blue dashed line is the trigger signal). The red dotted rectangle defines the interval in which the P3 wave is identifiable.
Fig 3.
Comparisons of the ANT-related potentials between hemispheres, for all conditions.
Blue and black for left and right hemispheres, respectively, by groups, and amplitudes are normalized (N at scales in the lower right corner, positive values above abscissae). Significance level of point-to-point comparisons with FDR-corrected scanning is marked on the parallel abscissae (time axis) below the graphs of each wave pair (blue rhombs, p ≤ 0.01; red rhombs, p ≤ 0.05). See Fig 2 for channel labeling.
Fig 4.
Comparisons of interhemispheric differences in ANT-related potentials between ANT conditions.
Each wave is the respective interhemispheric difference (right minus left) of ANT-related potentials for No cue (NoCue, blue), Neutral cue (NtCue, black), and Spatial cue (red) conditions, in A and C, and for Congruent (blue) and Incongruent (black) target conditions, in B and D. Point-to-point statistical comparisons (FDR corrected) between consecutive conditions (NoCue x NtCue, NtCue x SpCue, congruent x incongruent, related to alerting, orienting, and executive networks, respectively). Control groups in A and B, ADHD groups in C and D. Amplitudes are normalized (positive values above abscissae). ‘NoCue x NtCue’–comparison that showed significant differences. See Fig 2 for channel labeling.
Fig 5.
Comparisons of interhemispheric differences of the ANT-related potentials for NoCue and NtCue conditions in control group.
Detail from Fig 4 highlighting the waves in anterior- (F8-F7) and mid-temporal (T4-T3) regions; grey background marks time windows where significant differences were found.
Table 1.
Comparisons between groups of DSM scores, confounder variables, and eficiencies of the attention networks.
Table 2.
Correlation between DSM scores of ADHD and intraindividual variation in reaction time (IVRT) in ANT.
Table 3.
Comparisons of maximum P3 peak amplitude (μV) in the Pz channel between groups in all ANT cue and target conditions and the mean value of all conditions.
Fig 6.
Interhemispheric differences (asymmetries) in the mean values of all conditions in ADHD and control groups.
Control and ADHD groups in blue and red waves, respectively. The asymmetries of interest are delimited by dashed red boxes. Amplitudes are normalized (positive values above abscissae). See Fig 2, for channel labeling.
Fig 7.
ANT-related potentials of central and occipital channels and their differences in the ADHD group.
(A) ANT-related potentials in the central region. Superimposed potentials from the left (C3, green) and right (C4, blue) leads, and the arithmetic difference between them, revealing the rightward asymmetry (C4 –C3, dashed red line). (B) The same for potentials in occipital region from the left (O1) (green) and right (O2) (blue) leads. Amplitudes in μV.
Table 4.
Comparisons of interhemispheric asymmetry (mean amplitude) between groups.
Fig 8.
Scatter plots and linear regression models of correlation between asymmetries and DSM scores.
Left: mean amplitudes of O2-O1 asymmetry of all conditions (AllCd) (40–200ms after target onset) versus DSM-Inattention scores in the ADHD group. Right: mean amplitudes of C4-C3 asymmetry of AllCd (45–290ms after target onset) versus DSM hyperactivity+Impulsivity scores in all subjects (blue, Control group; green, ADHD group).
Table 5.
Correlations between asymmetries (mean amplitude) in occipital and central regions of different ANT conditions and DSM scores.
Fig 9.
Correlation between O2-O1 asymmetry and ANT performance.
O1-O2 (mean amplitude) of AllCd and accuracy (left), and efficiencies of the alerting (center) and executive networks (right) regarding accuracy.