Table 2 Summary of the behavioral and imaging findings in ASD.
Reference | Study type | Subjects | Age range | Method | Brain regions | Findings |
|---|---|---|---|---|---|---|
Hazlett et al.64 | A prospective and longitudinal study | High and low-risk ASD | 6–24 months | Structural brain MRI | Cortical surface area | Hyperexpansion of cortical surface area precedes brain volume overgrowth |
Nordahl et al.68 | A prospective and longitudinal study | ASD and typically developing | 2–4 years | Structural brain MRI | Amygdala | Increased total cerebral and amygdala volume |
Pote et al.65 | A prospective and longitudinal study | High and low-risk ASD | 4–36 months | Structural brain MRI | Cerebellum and subcortical regions | Larger cerebellum and subcortical volumes |
Schumann et al.71 | A prospective and longitudinal study | ASD and typically developing | 1.5–5 years | Structural brain MRI | Cerebral gray and white matter | Increase in cerebral gray and white matter specifically in frontal, temporal, and cingulate cortices |
A prospective and longitudinal study | High-risk and low-risk ASD | 6 months to 3 years | Structural brain MRI | Extra-axial cerebrospinal fluid | Increase in volume of extra-axial cerebrospinal fluid | |
Zhu et al.69 | Prospective and cross-sectional | ASD and typically developing | 2–5 years | Structural brain MRI | Amygdala | Larger bilateral amygdala volumes |
Conti et al.97 | Prospective and cross-sectional | ASD and other developmental delays | Below 36 months | DTI | White matter connectivity | The over-connectivity pattern in ASD occurred in networks involving the frontotemporal nodes and basal ganglia |
Fingher et al.86 | Prospective and cross-sectional | ASD and typically developing | <2.5 years | DTI | Corpus callosum | Fractional anisotropy and the cross-sectional area of the temporal corpus callosum tract were significantly larger |
Solso et al.94 | Prospective and longitudinal | ASD and typically developing | 12–48 months | DTI | Frontal lobe | Frontal fiber tracts displayed deviant early development and age-related changes |
Weinstein et al.84 | Prospective and cross-sectional | ASD and typically developing | 1.5–5.8 years | DTI | Corpus callosum left superior longitudinal fasciculus and right and left cingulum | Increase in fractional anisotropy was seen in corpus callosum as well as in the left cingulum |
Wolff et al.88 | A prospective and longitudinal study | High risk and ASD | 6–24 months | DTI | White matter fiber tract | Aberrant development of WM pathways may precede the manifestation of autistic symptoms in the first year of life |
Wolff et al.87 | A prospective and longitudinal study | High risk and ASD | 6–24 months | DTI | Cerebellum and corpus callosum | Aberrant structural properties of callosal and cerebellar white matter pathways were observed |
Xiao et al.98 | Prospective and cross-sectional | ASD and developmental delay | 2–3 years | Structural imaging and DTI | Gray and white matter volumes and corpus callosum, cingulate cortex, and limbic lobes | An increase in global gray and white matter volume and higher fractional anisotropy value was also observed in the corpus callosum, posterior cingulate cortex, and limbic lobes |
Ciarrusta et al.113 | Prospective and cross-sectional | High risk and typically developing | Neonates | Resting-state fMRI | Resting-state networks | Significantly high regional homogeneity within multiple resting-state networks |
Eggebrecht et al.103 | Prospective and longitudinal | High risk and typically developing | 12–24 months | fMRI | visual, dorsal attention and default mode network | Association between joint attention and these mentioned networks were found |
Eyler et al.105 | Prospective and longitudinal | ASD and typically developing | 12–48 months | Resting-state fMRI | Temporal | Abnormally right-lateralized temporal cortex response to language |
McKinnon et al.106 | Prospective and longitudinal | High risk and typically developing | 12–24 months | Resting-state fMRI | Dorsal attention, subcortical, and default mode network | Association between these networks and RRBs were found except that for self-injurious behaviors |
