Table I. Studies investigating typical development that are reviewed in this paper. Bold indicates study that examined age* diagnosis effect. *, no gender information; AD, autism; ADHD, attention deficit/hyperactivity disorder; PBD, pediatric bipolar disorder; FX, fragile X; DD, developmental delay; 22q, 22q11.2 deletion syndrome; WS, Williams syndrome; DS, Down syndrome; TS, Turner syndrome; TD, typically developing; (# F), number of female participants; yo, years old; mo, months old; MRI, magnetic resonance imaging; GMD, gray matter density; DTI, diffusion tensor imaging; ROI, region of interest; HARDI, high angular resolution diffusion imaging; ICA, independent components analysis; ‡ indicates study for which we have included a figure.

Study	N	Ages	Modality
Structural MRI
Giedd et al, 1999	145 (56 F)	4-22 overall	Brain wolume
Gogtay et al, 2004‡	13 (7 F)	4-21 yo overall	Brain volume
Sowell et al, 2002	35 (15 F)	7-16 yo	Brain volume
Sowell et al, 2003	1796(86 F)	7-87 yo	Brain volume (GMD)
Sowell et al, 2004	45 (22 F)	5-10 yo baseline	Cortical thickness
Hua et al, 2009‡	13 (6 F)	6-15 yo baseline	Brain volume
Tamnes et al, 2010	168 (87 F)	8-30 yo	Brain volume, cortical thickness, and DTI
Diffusion-weighted imaging
Klingberg et al, 1999	7 children, 5 adults, all male	8-12 and 20-31 yo	DTI - ROI
Schmithorst et al, 2002	33 (17 F)	5-18 yo	Voxel-wise DTI
Barnea-Goralyetal, 2005	34 (16 F)	6-19 yo	Voxel-wise DTI
Bonekamp et al, 2007	40 (18 F)	5-19 yo	DTI - ROI
Eluvathingal et al, 2007	31 (16 F)	6-17 yo	DTI - ROI (tract-based)
Qiu et al, 2008	1: 24 (11 F), 2: 27 (11 F), 3: 24 (13 F)	1:6-8, 2:9-12, 3:18-26 yo	Voxel-wise DTI
Lebel et al, 2008‡	202 (98 F)	5-30 yo	DTI - ROI (tract based)
Kochunov et al, 2010	831 (485 F)	11-90 yo	DTI - ROI (tract-based)
Hagmann et al, 2010	30 (17 F)	18 mo-18 yo	DTI - graph theory
Dennis et al, 2013‡	439 (267 F)	12,16, 20-30 yo	HARDI - graph theory
Dennis et al, 2013b	438(266 F)	12,18, 20-30 yo	HARDI - graph theory
Functional connectivity
Fair et al, 2007, 2008‡	210 (*)	7-9,10-15,19-31 yo	Seed-based func. conn.
Kelly et al, 2009	1:14 (4 F), 2: 12 (5 F), 3: 14 (5 F)	1:8-13, 2:14-17, 3:20-24 yo	Seed-based func. conn.
Dosenbach et al, 2010	238 (115 F)	7-30 yo	Seed-based func. conn.
Supekar et al, 2010	1: 23 (13 F), 2: 22 (11 F)	1: 7-9, 2: 19-22 yo	DTI, ICA func. conn.
Thomason et al, 2011	65 (32 F)	9-15 yo baseline	Seed/ICA func. conn.
JoIIes et al, 2011	1:19(10 F), 2: 29 (16 F)	1: 11-13, 2: 19-25 yo	ICA func. conn.