Table 1.
Characteristics of included studies. Legend for abbreviations, acronyms and symbols used in the table is provided in the footnote.
Ref.* | ADHD1 | Comparisons2 | ADHD Type | Comorb. | Stimul. | Withd. | Task(s) | Contrast(s) | # Foci | Correction for multiple comparisons** | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
n | M | F | Age M | Age SD | n | M | F | Age M | Age SD | |||||||||
Banich (1) | 23 | 14 | 9 | 20 | 1.7 | 23 | 13 | 10 | 19 | 0.9 | All: Co | No | N=20: lifetime N=14: current |
24 h | Color word stroop (variant) | 6 contrasts included in the meta-analysis§ | 20 (tot) | Cluster-wise protection; voxel level threshold: p = 0.01 (AFNI AlphaSim) |
Bayerl (2) | 30 | 16 | 14 | 31 | 0.6 | 30 | 16 | 14 | 31 | 8.4 | All: Co | No | All: naïve | N/A | 2-back working memory | C > A | 1 | Cluster-size thresholding (50 voxels); voxel level: uncorrected p = 0.001; (SPM99) |
Booth (3) | 12 | 8 | 4 | 9.4 | 1.2 | 12 | 7 | 5 | 9.3 | 12 | N=8: Co N=4: I |
No | All: current | 48 h | Go/No-Go Selective attention | C >A C > A |
17 3 |
Cluster-size thresholding (10 voxels); voxel level: uncorrected p < 0.001 (SPM99) |
Braet (4) | 20 | 17 | 3 | 14 | 2.1 | 38 | 31 | 7 | 13 | 1.9 | NS | NS | Some (NS): current | 24 h | SART (Go/No-Go) | C > A: Successful inhibition | 5 | NS for second-level analysis (AFNI) |
Cao (5) | 12 | 12 | 0 | 13 | 1.7 | 13 | 13 | 0 | 13 | 1.2 | N=7: Co N=5: I |
N=5: ODD N= 2: CD |
N=3: current | 2 wks | Cued target detection | C > A: Intrinsic alerting effect C > A: Phasic alerting effect C > A: Alerting effect |
3 4 3 |
Cluster-size thresholding (10 voxels); voxel level: uncorrected p < 0.001 (SPM2) |
Cerullo (6) | 10 | 7 | 3 | 14 | 2 | 13 | 7 | 6 | 15 | 1.9 | NS | N=2: ODD N=2: Tics |
N=8: current | Day of the scan | CPT-X | C > A A > C |
1 2 |
Cluster-size thresholding (137 voxels); voxel-level: uncorrected p < 0.05; (AFNI) |
Cubillo (7) | 11 | 11 | 0 | 29 | 1 | 14 | 14 | 0 | 28 | 2 | N=6: Co N=2: HI N=3: I |
N=8§§ | All: naïve | N/A | Tracking Stop | C > A: Successful stop-go trials C > A: Unsuccessful stop-go trials C > A: Switch task |
2 1 2 |
Cluster-mass threshold; voxel-wide significance: p < 0.05; cluster threshold: p<0.01 (XBAM) |
Cubillo (8) | 11 | 11 | 0 | 29 | 1 | 15 | 15 | 0 | 28 | 3 | N=6: Co N=2: HI N=3: I |
N=8§§ | All: naïve | N/A | Simon task | C > A: Incongruent-Congruent C > A: Oddball-Congruent |
1 1 |
Cluster-mass threshold; voxel-wide significance: p < 0.05; cluster threshold: p < 0.01 (XBAM) |
Cubillo (9) | 11 | 11 | 0 | 29 | 1 | 15 | 15 | 0 | 28 | 3 | N=6: Co N=2: HI N=3: I |
N=8§§ | All: naïve | N/A | Rewarded CPT | C > A: Effect of attention C > A: Effect of reward |
3 2 |
Cluster-mass threshold; voxel-wide significance: p < 0.05; cluster threshold: 0.01 (XBAM) |
Dibbets (10) | 16 | 16 | 0 | 29 | 6.4 | 13 | 13 | 0 | 29 | 6.4 | All: Co | No | N=14: current | 24 h | Modified Go/No-Go | A > C: Overall activation | 1 | Cluster-size thresholding (3 voxels); voxel-level: p < 0.05; (SPM2) |
Dibbets (11) | 15 | 15 | 0 | 29 | 6.2 | 14 | 14 | 0 | 29 | 6.4 | All: Co | No | N=14: current | 24 h | Switch | C > A A > C |
6 6 |
Cluster-level thresholding (1000 iterations; p < 0.05) (Brainvoyager QX) |
Dillo (12) | 15 | 11 | 4 | 21–42 | N/A | 15 | 11 | 4 | 21–46 | N/A | N=5: Co N=7: I N=3: HI |
No | Some (NS): current | 3 wks | Go/No-Go | A > C | 2 | N/S (SPM2) |
Durston (13) | 7 | 6 | 1 | 8.5 | 1.6 | 7 | 6 | 1 | 8.7 | 1.5 | N=4: Co N=3: I |
ODD or CD (NS) | All: current | 24 h | Go/No-Go | C > A: No-Go > Go A > C: No-Go > Go |
1 8 |
Cluster-size thresholding (3 voxels); voxel-level: p < 0.05; (NeuroImaging Software) |
Durston (14) Sample 1 | 10 | 8 | 2 | 12 | 2.6 | 10 | 8 | 2 | 12 | 2.1 | N=5: Co N=2: I N=3: HI |
N=4: ODD | N=5: current | 24 h | Variant Go/No-Go | C > A: Unexpected stimulus-Unexpected time | 1 | Cluster-size thresholding (5 voxels); voxel-level: p < 0.05; (SPM2) |
Durston (14) Sample 2 | 12 | 12 | 0 | 15 | 2.3 | 12 | 12 | 0 | 15 | 2.1 | N=9: Co N=3: HI |
N=4: ODD | N=9: current | 24 h | Variant Go/No-Go | C > A: Expected stimulus-Unexpected time C > A: Unexpected stimulus-Expected time |
1 2 |
Cluster-size thresholding (5 voxels); voxel-level: p < 0.05; (SPM2) |
Hale (15) | 10 | 9 | 1 | 35 | 8.1 | 10 | 9 | 1 | 27 | 4.1 | N=3: Co N=7: I |
N=1: GAD+ SoP+SP N=1: SP |
N=4: current | 2 wks | WAIS-Forward/Backward digit span | C > A: Backward A > C: Forward A > C: Backward |
5 7 3 |
Cluster-size thresholding (25 voxels); voxel-level: uncorrected p < 0.001; (SPM2) |
Karch (16) | 8 | 7 | 1 | 38 | 7.8 | 8 | 7 | 1 | 38 | 6.6 | All: Co | No | All: naïve | N/A | Auditory Go/No-Go (modified) | C > A | 7 | Cluster-size thresholding; uncorrected p < 0.001; threshold: 10 voxels (BrainVoyager) |
Kobel (17) | 14 | 14 | 0 | 10 | 1.3 | 12 | 12 | 0 | 11 | 1.6 | N=9: Co N=5: I |
N=5: ODD-CD, N=4: GAD | All: current | 24 h | N-back | C > A: averaged 2-and 3-back | 5 | Family-wise error correction (p < 0.05); cluster size: 10 voxels (SPM 5) |
Kobel (18) | 14 | 14 | 0 | 10 | 1.3 | 12 | 12 | 0 | 11 | 1.6 | N=9: Co N=5: I |
N=5: ODD/CD N=4: GAD |
All: current | No | N-back | C > A: Activation in 3-back task | 1 | Correction applied but type of correction NS (SPM 5) |
Konrad (19) | 16 | 16 | 0 | 10 | 1.9 | 16 | 16 | 0 | 10 | 1.3 | N=9: Co N=6: I N=1: HI |
N=5: ODD N=3: AD |
All: naïve | N/A | Attention Network Test (modified) | C > A: Alerting C > A: Exec. Control A > C: Alerting A > C: Reorienting A > C: Exec. control |
1 2 1 3 1 |
Cluster-size thresholding (10 voxels); uncorrected p < 0.001; (SPM2) |
Kooistra (20) | 10 | 10 | 0 | 22 | NS | 10 | 10 | 0 | 22 | NS | NS | N/A | No after age 16 y | N/A | Go/No-Go | C > A: Go A > C: Go |
16 2 |
Corrected cluster significance threshold: p= 0.01 (FSL) |
Krauel (21) | 12 | 12 | 0 | 15 | 0.7 | 12 | 12 | 0 | 15 | 1.3 | N=6: Co N=5: I N=1: HI |
N=3:ODD N=2: CD |
N=5: current | 24 h | Recognition memory | C > A: Neutral A > C: Emotional A > C: Neutral |
1 4 4 |
Cluster-size thresholding (10 voxels); voxel-level: uncorrected p < 0.001; (SPM99) |
Mostofsky (22) | 11 | 8 | 3 | 10 | 1.2 | 11 | 8 | 3 | 10 | 1.4 | N=9: Co N=2: I |
No | N=8: current | 24 h | Sequential finger tapping | C > A | 2 | Cluster-size thresholding (84 voxels); voxel-level: uncorrected p < 0.001; (SPM99) |
Passarotti (23) | 15 | 12 | 3 | 13 | 2.6 | 14 | 7 | 7 | 14 | 2.4 | All: C | No | N=5: current | Over a 3-week period | Emotional valence stroop | C > A: Negative > neutral C > A: Positive > neutral words A > C: Negative > neutral words A > C: Positive > neutral words |
2 2 4 5 |
Contiguity threshold (uncorrected p < 0.01); experiment-wise Type 1: p < 0.02 (corrected) (AFNI AlphaSim) |
Passarotti (24) | 14 | 9 | 5 | 13 | 2.3 | 19 | 9 | 10 | 14 | 3.1 | All: Co | No | N/S | At least 4 days | Affective 2-back working memory | C > A: Angry > neutral faces A > C: Angry > neutral faces A > C: Happy > neutral faces |
13 1 12 |
Contiguity threshold (uncorrected p < 0.01); experiment-wise Type 1: p < 0.02 (corrected) (AFNI AlphaSim) |
Passarotti (25) | 11 | 6 | 5 | 13 | 2.7 | 15 | 7 | 8 | 14 | 3.1 | All: Co | No | N=6: current | 3 wks | Response Inhibition | C > A A > C |
7 3 |
Contiguity threshold (uncorrected p < 0.01); experiment-wise Type 1: p < 0.02 (corrected) (AFNI AlphaSim) |
Prehen-Kristensen (26) | 12 | NS | NS | 13 | 1.8 | 12 | NS | NS | 14 | 2 | N=12: Co; N= 2: I | N=5: ODD | All: current | 48 h | Delayed-match-to-sample paradigm | C > A | 15 | Cluster-size thresholding (5 voxels); voxel-level: p < 0.05; (SPM5) |
Rubia (27) | 7 | 7 | 0 | 16 | NS | 9 | 9 | 0 | 15 | NS | All: Co | CD (NS) | (NS) | 1 wk | Stop Delay |
C > A C > A |
4 2 |
Permutation; Voxel-wise probability Type I error: 0.05 |
Rubia (28) | 16 | 16 | 0 | 13 | 2.1 | 21 | 21 | 0 | 14 | 1.6 | All: Co | N=5: CD | All: naïve | N/A | Stop | C > A: Successful > unsuccessful inhibition C > A: Unsuccessful inhibition > baseline go |
2 2 |
Cluster level difference; < 1 false activated cluster at p < 0.05 (voxel comparison); p < 0.01 (cluster comparison) |
Rubia (29) | 17 | 17 | 0 | 14 | 2 | 18 | 18 | 0 | 13 | 2 | All: Co | No | All: naïve | N/A | Oddball | C > A: Successful oddball > standard C >A: Standard > oddball |
3 2 |
Cluster level difference; < 1 false activated cluster at p < 0.05 (voxel comparison); p < 0.01 (cluster comparison) |
Rubia (30) | 20 | 20 | 0 | 13 | 1.5 | 20 | 20 | 0 | 14 | 2 | All: Co | No | All: naïve | N/A | Tracking stop | C > A: Successful > failed stop C > A: Failed stop > go C > A: Go > stop |
1 1 1 |
Cluster level difference; < 1 false activated cluster at p < 0.05 (voxel comparison); p < 0.03 (cluster comparison) |
Rubia (31) | 18 | 18 | 0 | 13 | 1 | 16 | 16 | 0 | 13 | 3 | All: Co | No | All: naïve | N/A | Rewarded CPT | C > A: Effect of attention C > A: Effect of reward A > C: Effect of attention |
2 1 9 |
Cluster level difference; < 1 false activated cluster at p < 0.05 (voxel comparison); p < 0.01 (cluster comparison) |
Rubia (32) | 20 | 20 | 0 | 13 | 1.4 | 20 | 20 | 0 | 14 | 1.9 | All: Co | No | All: naïve | N/A | Simon | C > A: Incongruent > oddball C > A: Oddball > congruent |
2 2 |
Cluster level difference; < 1 false activated cluster at p < 0.05 for both voxel comparison and cluster comparison |
Rubia (33) | 13 | 13 | 0 | 13 | 1.4 | 13 | 13 | 0 | 13 | 1.8 | All: Co | N=1: CD | All: naïve | N/A | Rewarded CPT | C > A: Attention C > A: Reward A > C: Reward |
13 2 4 |
Cluster level difference; < 1 false activated cluster at p < 0.05 (voxel comparison); p < 0.02 (cluster comparison) (XBAM) |
Rubia (34) Study 1 |
10 | 10 | 0 | 14 | 2 | 10 | 10 | 0 | 15 | 4 | All: Co | N=1: CD | N= 4: naïve; N= 6: current | 36 h (N=6) | Delay discounting | C > A | 6 | Cluster level difference; < 1 false activated cluster at p < 0.05 (voxel comparison); p < 0.006 (cluster comparison) |
Rubia (34) Study 2 |
12 | 12 | 0 | 13 | 1 | 12 | 12 | 0 | 13 | 1 | All: Co | N=1: CD | All: naïve | N/A | Time discrimin. | C > A A > C |
1 2 |
Cluster level difference; < 1 false activated cluster at p < 0.05 for voxel comparison and p < 0.006 for cluster comparison |
Rubia (35) | 14 | 14 | 0 | 13 | 1.1 | 20 | 20 | 0 | 14 | 1.9 | All: Co | No | All: naïve | N/A | Switch | C > A | 2 | Cluster level difference; < 1 false activated cluster at p < 0.05 for both voxel and cluster comparison (XBAM) |
Rubia (36) | 18 | 18 | 0 | 14 | 1.1 | 20 | 20 | 0 | 15 | 1.1 | All: Co | No | All: naïve | N/A | Visual tracking stop Meiran Switch |
C > A: Successful-stop C > A: Failed-stop C > A |
1 2 3 |
Cluster level difference; < 1 false activated cluster at p < 0.05 for voxel comparison and p < 0.003 for cluster comparison (XBAM) |
Rubia (37) | 12 | 12 | 0 | 13 | 1 | 13 | 13 | 0 | 13 | 1 | All: Co | No | All: naïve | N/A | Visual tracking stop | C > A: Successful inhibition C > A: Inhibition failure |
13 13 |
Threshold-Free Cluster Enhancement (p < 0.05) |
Rubia (38) | 12 | 12 | 0 | 13 | 1 | 13 | 13 | 0 | 13 | 1 | All: Co | No | All: naïve | N/A | Simon | C > A: Simon > oddball condition | 4 | Cluster level difference; < 1 false activated cluster at p < 0.05 for voxel comparison and p < 0.01 for cluster comparison (XBAM) |
Rubia (39) | 18 | 18 | 0 | 14 | 2 | 20 | 20 | 0 | 16 | 1 | All: Co | No | All: naïve | N/A | Simon | C > A: Oddball > congruent C > A: Incongruent > oddball |
2 2 |
Cluster level difference; < 1 false activated cluster at p < 0.05 for voxel comparison and p < 0.01 for cluster comparison (XBAM) |
Schulz (40) | 5† | 5 | 0 | 18 | 1.3 | 5 | 5 | 0 | 18 | 1.4 | N=1: Co N=3: I N=1: HI |
N=1: CD | N=4: treated†† | N/A | Go/No-Go | C > A: Correct No-Go > correct GO A > C: Correct No-Go > correct GO |
2 3 |
Cluster-size thresholding (120 voxels); voxel level: uncorrected p < 0.01 (SPM99) |
Sheridan (41) | 10 | 0 | 10 | 15 | 2 | 10 | 0 | 10 | 15 | 1.3 | N=6: Co N=4: I |
N=2: ODD N=2: SP |
N=5:‡ N=2: current |
24 h | Delay match-to-sample | C > A: Activation at high load period | 2 | Gaussian field theory; p= 0.05 corrected at cluster level (fmristat program) |
Silk (42) | 12 | 12 | 0 | 11 | 1.5 | 12 | 12 | 0 | 11 | 1.5 | All: Co | No | All: naïve | N/A | Raven’s Standard Progressive Matrices | C > A | 45 | Clusters of voxels (z > 2.33) with cluster level p corr < 0.05; (FSL) |
Silk (43) | 7 | 7 | 0 | 14 | 1.8 | 7 | 7 | 0 | 15 | 1.8 | All: Co | No | All: naïve | N/A | Mental rotation | C > A A > C |
8 4 |
Voxel level p (uncorr) < 0.001; cluster level p corr < 0.05 |
Smith (44) | 17 14 |
17 14 |
0 0 |
13 13 |
2 1.8 |
18 27 |
18 27 |
0 0 |
14 14 |
2 1.8 |
All: Co | N=5: CD | All: naïve | N/A | Go/No-Go Switch |
C > A: Successful No-Go stimuli C> A: Switch |
1 9 |
Cluster level difference; < 1 false activated cluster at p < 0.05 (voxel comparison) and p < 0.01 (cluster comparison) |
Smith (45) | 21 | 21 | 0 | 13 | 1.6 | 17 | 17 | 0 | 14 | 2.1 | All: Co | N=3: CD/ODD | All: naïve | N/A | Time discrimination | C > A: Time discrimination > temporal order judgment | 2 | Cluster level difference; < 1 false activated cluster at p < 0.05 (voxel comparison) and p < 0.01 (cluster comparison) (XBAM) |
Spinelli (46) | 13 | 9 | 4 | 11 | 1.4 | 17 | 8 | 9 | 11 | 1.2 | N=10: Co; N=3: | N=3: ODD N=1: SP |
N=2: current | 24 h | Go/No-Go | A > C: Pre-Error vs. Pre-Correct Inhibition | 2 | Spatial extent cluster size threshold to achieve a corrected statistical threshold of p= 0.05 (SPM5) |
Spinelli (47) | 13 | 9 | 4 | 11 | 1.4 | 17 | 8 | 9 | 11 | 1.2 | N=10: Co; N=3: | N=3: ODD N=1: SP |
N=2: current | 24 h | Go/No-Go | A > C: Post-error versus post-correct inhibition trials | 9 | Spatial extent cluster size threshold to achieve a corrected statistical threshold of p= 0.05 (SPM5) |
Strohle (48) | 10 | 10 | 0 | 32 | 8.1 | 10 | 10 | 0 | 32 | 9.9 | N=4: Co N=4:I N=2: HI |
No | All: naïve | N/A | Monetary Incentive Delay | C > A: Anticipation of gain > non gain A > C: outcome of gain > non gain |
1 7 |
p < 0.05 False Discovery Rate corrected (SPM2) |
Tamm (49) | 10 | 10 | 0 | 16 | 1.4 | 12 | 12 | 0 | 16 | 0.8 | All: Co | No | N=5 current | 18 h | Modified Go/No-Go | C > A: “A-B “ contrast A > C: “A-B” contrast |
1 1 |
Deactivation mask (Z= 1.67; p < 0.05) (SPM99) |
Tamm (50) | 14 | 14 | 0 | 14–18 | N/A | 12 | 12 | 0 | 14–18 | N/A | All: Co | No | N=5: current | 18 h | Oddball | C > A: activation during the oddball event | 4 | NS |
Valera (51) | 20 | 12 | 8 | 34 | 11.8 | 20 | 12 | 8 | 33 | 11 | NS | No | N=10: lifetime | 24 h | Variant of visual N-back test | C > A: 2-back minus X-task contrast | 2 | p = 0.001 (uncorrected) with extent threshold determined by Gaussian random field theory (SPM99) |
Valera (52) | 21 | 15 | 6 | 34 | 10.1 | 19 | 12 | 7 | 33 | 11 | N=5: Co N=12: I |
No | N=9: current | 24 h | Paced and unpaced finger tapping | C > A: Paced finger tapping C > A: Unpaced finger tapping |
24 17 |
p < 0.05, family-wise error corrected, with extent threshold of 20 contiguous voxels (SPM5) |
Valera (53) | 44 | 23 | 21 | 37 | 11 | 49 | 23 | 26 | 33 | 10 | N=13 Co N=17: I N=1: HI |
No | N=18: current | 24 h | 2-back | C > A: 2-back visual memory task | 2 | p < 0.05, corrected (Gaussian random field theory) (SPM2) |
Vance (54) | 12 | 12 | 0 | 11 | 1.5 | 12 | 12 | 0 | 10 | 1.3 | All: Co | No | All: naïve | N/A | Mental rotation | C > A | 4 | Cluster level threshold p corrected < 0.05 (FSL) |
Wolf (55) | 13 | 13 | 0 | 22 | 4.4 | 12 | 12 | 0 | 22 | 4.7 | N=9: Co N=2: I N=2: HI |
No | All: lifetime | N=6: At least 6 wks; N=6: 3 days |
Cognitive Activation | C > A: Increasing working memory load | 5 | p < 0.05 corrected using False Discovery Rate (SPM5) |
Total number of ADHD participants (After removing complete overlap but including partial overlap of participants across studies from the same research groups): 741;
Total number of comparisons (After removing complete overlap but including partial overlap of participants across studies from the same research groups): 801.
Abbreviations:
M: Males; F: Females; Age M: mean age; Age SD: standard deviation of age; Comorb.: Psychiatric comorbidities; Stimul.: Treatment with psychostimulants; Withd.: Withdrawal from psychostimulants.
Acronyms (in alphabetical order):
A= ADHD; AD: Anxiety Disorders; AFNI: Analysis of Functional NeuroImages; C= Comparisons; CD: Conduct Disorder; Co: ADHD combined type; FSL: FMRIB Software Library; GAD: Generalized Anxiety Disorder; HI: ADHD hyperactive-impulsive type; I: ADHD inattentive type; MD: Mood Disorders; ND: Nicotine Dependence; NS: Not Specified; ODD: Oppositional Defiant Disorder; SoP: Social Phobia; SP: Specific Phobia; SPM: Statistical Parametric Mapping; SUD: Substance Use Disorders; XBAM: X Activation Brain Maps.
Number in parenthesis after first author refers to reference # provided in Supplemental Material A3;
The software used for the analyses is provided in parenthesis when indicated in the paper;
C > A: Blocked activity-congruent > fixation baseline, C > A: Blocked activity-incongruent > fixation baseline, C > A: Blocked activity-neutral > fixation baseline, A > C: Blocked activity-congruent >fixation baseline, A > C: Blocked activity-incongruent > fixation baseline, A > C: Blocked activity-neutral > fixation baseline;
N=1: AD; N=3: MD; N=1: CD; N=2: SUD; N=1: ND;
Only individuals with persistent ADHD (N=5) were included in the analysis; remitters (N=5) were excluded;
stopped 6 months before the study;
stopped 1 year before the study.