Table 2.

Linear Mixed Effects Models of Volumetric Brain Development in ASD

	ASD Intercept B (SE)	Group Effect B (SE)	Age B (SE)	Age² B (SE)	Group × Age B (SE)	Group × Age² B (SE)	FSIQ B (SE)
Whole Brain	1122.18 (9.7)	−3.9 (14.1)	−4.5^*** (.25)	.04^* (.01)	1.24^** (.42)	−.10^** (.02)	1.0^* (.41)
Gray Matter Total	633.8 (5.3)	−3.5 (7.7)	−6.3^*** (.18)	.14^*** (.01)	1.0^** (.30)	−.06^** (.02)	.61^** (.21)
Gray Matter: Cortical	565.7 (4.9)	−2.3 (7.1)	−6.1^*** (.17)	.14^*** (.01)	.96^** (.29)	−.06^** (.02)	.54^* (.19)
Gray Matter: Subcortical	66.8 (.52)	−1.0 (.76)	−.11^*** (.01)	−.006^*** (.001)	.07^* (.02)	−.005^** (.001)	.06^** (.02)
White Matter	381.9 (18.8)	−2.6 (6.0)	1.08^*** (.10)	−.07^*** (.006)	.21 (.17)	−.02^* (.01)	.37^* (.17)
Ventricles	18.6 (.73)	−2.0^* (.98)	.25^*** (.02)	-	−.10^** (.03)	-	-
Cerebellum	148.3 (1.4)	−.25 (2.0)	−.17^** (.05)	−.02^*** (.002)	.04 (.08)	-	.15^* (.06)
Thalamus	16.4 (.14)	−.07 (.20)	−.04^*** (.005)	−.002^*** (.0003)	.02^* (.009)	-	.01^* (.005)
Caudate	8.6 (.11)	−.24 (.16)	−.03^*** (.002)	−.0005^** (.0001)	-	-	.01^* (.004)
Corpus Callosum	3.56 (.05)	.05 (.07)	.01^*** (.002)	−.001^*** (.0001)	.008^* (.003)	-	-
Lobes
Frontal	213.5 (2.1)	−1.1 (3.1)	−2.6^*** (.08)	.06^*** (.005)	.32^* (.13)	−.02^** (.008)	.28^** (.08)
Temporal	129.0 (1.2)	.39 (1.6)	−.95^*** (.03)	.01^*** (.002)	.15^* (.06)	−.01^* (.004)	-
Parietal	148.5 (1.4)	−.13 (2.05)	−1.99^*** (.06)	.05^*** (.004)	.39^*** (.10)	−.02^** (.007)	.14^* (.05)
Occipital	59.3 (.67)	−.02 (.9)	−.48^*** (.02)	.012^*** (.001)	.12^*** (.032)	−.006^* (.002)	-
TGM over WBV	.56 (.001)	−.001 (.002)	−.003^*** (.00007)	.00008^*** (.00001)	.0001 (.0001)	-	-
VBR	.016 (.0006)	−.0018^* (.0008)	.0003^*** (.00002)	-	−.0001^** (.00003)	-	-

^***

corrected p<.001,

^**

corrected p<.01,

corrected p<.05;

B: Beta value; SE: standard error; TGM: total gray matter; WBV: whole brain volume; VBR: ventricle to whole brain ratio; - effect not included in best fitting model.