Supplemental Materials

Supplemental Figures

Figure S1. Group differences after including IQ as a covariate. (A) The Control group exhibited significantly greater linear increases in activation across working memory loads than the Impaired ADHD group in left inferior frontal junction, supracalcarine cortex, lingual gyrus, and cerebellum. (B) The Unimpaired ADHD group exhibited significantly greater linear increases in activation across working memory loads than the Impaired ADHD group in the cingulate gyrus, left inferior frontal junction, left caudate, thalamus, left lingual gyrus, and cerebellum. (C) There were no significant differences in activation between the Control and Unimpaired ADHD groups. Uncorrected height threshold of p < 0.005 (z > 2.57), whole-brain cluster corrected for multiple comparisons, corrected p < 0.05.

1

Figure S2. Group differences after removal of ADHD patients from both the Impaired and Unimpaired groups who were currently taking medications to treat their ADHD. (A) The Control group exhibited significantly greater linear increases in activation across working memory loads than the Impaired ADHD group in left inferior frontal junction, intraparietal sulcus, lingual gyrus, and cerebellum. (B) The Unimpaired ADHD group exhibited significantly greater linear increases in activation across working memory loads than the Impaired ADHD group in the cingulate gyrus, left inferior frontal junction, left caudate, thalamus, left insula, left lingual gyrus, and cerebellum. (C) There were no significant differences in activation between the Control and Unimpaired ADHD groups. Uncorrected height threshold of p < 0.005 (z > 2.57), whole-brain cluster corrected for multiple comparisons, corrected p < 0.05.

2

Supplemental Tables

Table S1. Sociodemographic and Clinical CharacteristicsControls(N = 17)

Unimpaired ADHD

(N = 16)

Impaired ADHD

(N = 17)N (%) N (%) N (%)

MeanSD MeanSD MeanSD

Male 11 (65) 10 (62) 9 (53)Baseline age 10.13.0 9.63.1 11.34.2Current age 28.74.0 28.74.1 29.16.1

Baseline (DSM-III) symptoms 1.11.2a***,b*** 10.52.3 11.22.3Current (DSM-IV) symptoms 0.31.4a**,b*** 3.93.5 4.33.8

WASI Full IQ 1207.5 b*** 1138.5 b** 10410.6D-KEFS Color Word Interference 123.9 11.92.8 102.9D-KEFS Trail Making 11.52.6 10.62.4 10.13.5ADHD Medication 0 (0)a***,b*** 5 (31) 3 (17)a vs. Unimpaired ADHDb vs. Impaired ADHD*p<0.05, **p<0.01, ***p<0.001

3

Table S2. fMRI Results Linear ContrastRegion Peak z-values x y z

Control group only (N=17)L middle frontal gyrus 6.8 -28 6 47L cerebellum 6.7 -25 -59 -22R cerebellum 6.4 36 -63 -17R superior parietal lobule 6.2 30 -55 51R middle frontal gyrus 5.9 41 42 22L superior parietal lobule 5.9 -41 -36 42

Unimpaired ADHD group only (N=16)R anterior insula 6.7 27 24 -6R cingulate gyrus 6.6 3 36 28L middle frontal gyrus 5.1 -35 9 49R middle frontal gyrus 4.4 33 9 52R caudate 5.0 13 9 10L caudate 4.6 -12 9 10L superior parietal lobule 6.8 -40 -41 43R superior parietal lobule 6.4 33 -49 39R cerebellum 5.8 5 -73 -13L cerebellum 5.7 -32 -64 -18

Impaired ADHD group only (N=17)R middle frontal gyrus 6.4 27 18 48R superior parietal lobule 5.2 38 -43 44R anterior insula 5.4 31 25 -4L superior parietal lobule 5.2 -27 -48 42R cerebellum 5.3 35 -62 -39L cerebellum 4.5 -34 -66 -36L middle frontal gyrus 4.5 -42 25 24

Control group > Impaired ADHD groupL lingual gyrus 4.9 -21 -70 -12L precuneous cortex 4.8 -9 -60 50L inferior frontal gyrus 4.2 -45 4 19L supracalcarine cortex 4.8 -21 -64 29L parietal operculum 4.8 -39 -44 16

Unimpaired ADHD group > Impaired ADHD groupR lingual gyrus 5.2 10 -82 -9L putamen 4.7 -24 19 -4L insula 4.6 -28 19 -5L superior parietal lobule 5.6 -26 -63 46L precuneus 4.7 -3 -50 47L lateral occipital cortex 4.6 -37 -37 33L inferior frontal gyrus 4.1 -44 8 21

Control group > Unimpaired ADHD group

4

No significant differences - - - -L = left; R = right

5