Self-injurious behaviours are associated with alterations in the somatosensory system in children with autism spectrum disorder.

Authors

Emma G Duerden, Department of Diagnostic Imaging, Hospital for Sick Children, 555 University Avenue, Toronto, ON M5G 1X8, Canada & Program in Neurosciences and Mental Health, Hospital for Sick Children, Toronto, ON, CanadaFollow
Dallas Card, Department of Diagnostic Imaging, Hospital for Sick Children, 555 University Avenue, Toronto, ON M5G 1X8, Canada
S Wendy Roberts, Department of Diagnostic Imaging, Hospital for Sick Children, 555 University Avenue, Toronto, ON M5G 1X8, Canada
Kathleen M Mak-Fan, Department of Diagnostic Imaging, Hospital for Sick Children, 555 University Avenue, Toronto, ON M5G 1X8, Canada & Department of Psychology, University of Toronto, Toronto, ON, Canada
M Mallar Chakravarty, Kimel Family Translational Imaging-Genetics Research Laboratory, Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada & Department of Psychiatry and Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, Canada
Jason P Lerch, Program in Neurosciences and Mental Health, Hospital for Sick Children, Toronto, ON, Canada & Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
Margot J Taylor, Department of Diagnostic Imaging, Hospital for Sick Children, 555 University Avenue, Toronto, ON M5G 1X8, Canada & Program in Neurosciences and Mental Health, Hospital for Sick Children, Toronto, ON, Canada & Department of Psychology, University of Toronto, Toronto, ON, Canada

Document Type

Article

Publication Date

7-1-2014

Journal

Brain Struct Funct

Volume

219

Issue

4

First Page

1251

Last Page

1261

URL with Digital Object Identifier

10.1007/s00429-013-0562-2

Abstract

Children with autism spectrum disorder (ASD) frequently engage in self-injurious behaviours, often in the absence of reporting pain. Previous research suggests that altered pain sensitivity and repeated exposure to noxious stimuli are associated with morphological changes in somatosensory and limbic cortices. Further evidence from postmortem studies with self-injurious adults has indicated alterations in the structure and organization of the temporal lobes; however, the effect of self-injurious behaviour on cortical development in children with ASD has not yet been determined. Thirty children and adolescents (mean age = 10.6 ± 2.5 years; range 7-15 years; 29 males) with a clinical diagnosis of ASD and 30 typically developing children (N = 30, mean age = 10.7 ± 2.5 years; range 7-15 years, 26 males) underwent T1-weighted magnetic resonance and diffusion tensor imaging. No between-group differences were seen in cerebral volume, surface area or cortical thickness. Within the ASD group, self-injury scores negatively correlated with thickness in the right superior parietal lobule t = 6.3, p < 0.0001, bilateral primary somatosensory cortices (SI) (right: t = 4.4, p = 0.02; left: t = 4.48, p = 0.004) and the volume of the left ventroposterior (VP) nucleus of the thalamus (r = -0.52, p = 0.008). Based on these findings, we performed an atlas-based region-of-interest diffusion tensor imaging analysis between SI and the VP nucleus and found that children who engaged in self-injury had significantly lower fractional anisotropy (r = -0.4, p = 0.04) and higher mean diffusivity (r = 0.5, p = 0.03) values in the territory of the left posterior limb of the internal capsule. Additionally, greater incidence of self-injury was associated with increased radial diffusivity values in bilateral posterior limbs of the internal capsule (left: r = 0.5, p = 0.02; right: r = 0.5, p = 0.009) and corona radiata (left: r = 0.6, p = 0.005; right: r = 0.5, p = 0.009). Results indicate that self-injury is related to alterations in somatosensory cortical and subcortical regions and their supporting white-matter pathways. Findings could reflect use-dependent plasticity in the somatosensory system or disrupted brain development that could serve as a risk marker for self-injury.