BACKGROUND: Diffusion tensor imaging (DTI) has been used over the past decade to study structural differences in the brains of children with autism compared with typically developing children. These studies generally find reduced fractional anisotropy (FA) and increased mean diffusivity (MD) in children with autism; however, the regional pattern of findings varies greatly. METHODS: We used DTI to investigate the brains of sedated children with autism (n = 39) and naturally asleep typically developing children (n = 39) between 2 and 8 years of age. Tract based spatial statistics and whole brain voxel-wise analysis were performed to investigate the regional distribution of differences between groups. RESULTS: In children with autism, we found significantly reduced FA in widespread regions and increased MD only in posterior brain regions. Significant age × group interaction was found, indicating a difference in developmental trends of FA and MD between children with autism and typically developing children. The magnitude of the measured differences between groups was small, on the order of approximately 1%-2%. Subjects and control subjects showed distinct regional differences in imaging artifacts that can affect DTI measures. CONCLUSIONS: We found statistically significant differences in DTI metrics between children with autism and typically developing children, including different developmental trends of these metrics. However, this study indicates that between-group differences in DTI studies of autism should be interpreted with caution, because their small magnitude make these measurements particularly vulnerable to the effects of artifacts and confounds, which might lead to false positive and/or false negative biological inferences.
BACKGROUND: Diffusion tensor imaging (DTI) has been used over the past decade to study structural differences in the brains of children with autism compared with typically developing children. These studies generally find reduced fractional anisotropy (FA) and increased mean diffusivity (MD) in children with autism; however, the regional pattern of findings varies greatly. METHODS: We used DTI to investigate the brains of sedated children with autism (n = 39) and naturally asleep typically developing children (n = 39) between 2 and 8 years of age. Tract based spatial statistics and whole brain voxel-wise analysis were performed to investigate the regional distribution of differences between groups. RESULTS: In children with autism, we found significantly reduced FA in widespread regions and increased MD only in posterior brain regions. Significant age × group interaction was found, indicating a difference in developmental trends of FA and MD between children with autism and typically developing children. The magnitude of the measured differences between groups was small, on the order of approximately 1%-2%. Subjects and control subjects showed distinct regional differences in imaging artifacts that can affect DTI measures. CONCLUSIONS: We found statistically significant differences in DTI metrics between children with autism and typically developing children, including different developmental trends of these metrics. However, this study indicates that between-group differences in DTI studies of autism should be interpreted with caution, because their small magnitude make these measurements particularly vulnerable to the effects of artifacts and confounds, which might lead to false positive and/or false negative biological inferences.
Authors: Hui Zhang; Brian B Avants; Paul A Yushkevich; John H Woo; Sumei Wang; Leo F McCluskey; Lauren B Elman; Elias R Melhem; James C Gee Journal: IEEE Trans Med Imaging Date: 2007-11 Impact factor: 10.048
Authors: Jee Eun Lee; Erin D Bigler; Andrew L Alexander; Mariana Lazar; Molly B DuBray; Moo K Chung; Michael Johnson; Jubel Morgan; Judith N Miller; William M McMahon; Jeffrey Lu; Eun-Kee Jeong; Janet E Lainhart Journal: Neurosci Lett Date: 2007-08-06 Impact factor: 3.046
Authors: Douglas C Dean; Brittany G Travers; Nagesh Adluru; Do P M Tromp; Daniel J Destiche; Danica Samsin; Molly B Prigge; Brandon A Zielinski; P Thomas Fletcher; Jeffrey S Anderson; Alyson L Froehlich; Erin D Bigler; Nicholas Lange; Janet E Lainhart; Andrew L Alexander Journal: Brain Connect Date: 2016-05-05
Authors: E Conti; J Mitra; S Calderoni; K Pannek; K K Shen; A Pagnozzi; S Rose; S Mazzotti; D Scelfo; M Tosetti; F Muratori; G Cioni; A Guzzetta Journal: Hum Brain Mapp Date: 2017-01-17 Impact factor: 5.038
Authors: Pallavi Rane; David Cochran; Steven M Hodge; Christian Haselgrove; David N Kennedy; Jean A Frazier Journal: Harv Rev Psychiatry Date: 2015 Jul-Aug Impact factor: 3.732