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)

¹Total number of ADHD participants (After removing complete overlap but including partial overlap of participants across studies from the same research groups): 741;

²Total 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.