White-matter relaxation time and myelin water fraction differences in young adults with autism

TY - JOUR

T1 - White-matter relaxation time and myelin water fraction differences in young adults with autism

AU - Zinkstok, Janneke R.

AU - Daly, E.

AU - Ecker, C.

AU - Williams, S. C R

AU - Murphy, D. G M

AU - Bailey, A. J.

AU - Baron-Cohen, S.

AU - Bolton, P. F.

AU - Bullmore, E. T.

AU - Carrington, S.

AU - Chakrabarti, B.

AU - Daly, E. M.

AU - Deoni, Sean C. L.

AU - Ecker, C.

AU - Happe, F.

AU - Henty, J.

AU - Jezzard, P

AU - Johnston, Patrick

AU - Jones, D. K.

AU - Lombardo, Michael V.

AU - Madden, A.

AU - Mullins, D.

AU - Murphy, Clodagh

AU - Murphy, D. G.

AU - Pasco, G.

AU - Sadek, Susan A.

AU - Spain, Debbie

AU - Steward, R.

AU - Suckling, John

AU - Wheelwright, S

AU - Williams, Steven

PY - 2015/3/12

Y1 - 2015/3/12

N2 - BackgroundIncreasing evidence suggests that autism is associated with abnormal white-matter (WM) anatomy and impaired brain ‘connectivity’. While myelin plays a critical role in synchronized brain communication, its aetiological role in autistic symptoms has only been indirectly addressed by WM volumetric, relaxometry and diffusion tensor imaging studies. A potentially more specific measure of myelin content, termed myelin water fraction (MWF), could provide improved sensitivity to myelin alteration in autism.Method We performed a cross-sectional imaging study that compared 14 individuals with autism and 14 age- and IQ-matched controls. T1 relaxation times (T1), T2 relaxation times (T2) and MWF values were compared between autistic subjects, diagnosed using the Autism Diagnostic Interview – Revised (ADI-R), with current symptoms assessed using the Autism Diagnostic Observation Schedule (ADOS) and typical healthy controls. Correlations between T1, T2 and MWF values with clinical measures [ADI-R, ADOS, and the Autism Quotient (AQ)] were also assessed.Results Individuals with autism showed widespread WM T1 and MWF differences compared to typical controls. Within autistic individuals, worse current social interaction skill as measured by the ADOS was related to reduced MWF although not T1. No significant differences or correlations with symptoms were observed with respect to T2.Conclusions Autistic individuals have significantly lower global MWF and higher T1, suggesting widespread alteration in tissue microstructure and biochemistry. Areas of difference, including thalamic projections, cerebellum and cingulum, have previously been implicated in the disorder; however, this is the first study to specifically indicate myelin alteration in these regions.

AB - BackgroundIncreasing evidence suggests that autism is associated with abnormal white-matter (WM) anatomy and impaired brain ‘connectivity’. While myelin plays a critical role in synchronized brain communication, its aetiological role in autistic symptoms has only been indirectly addressed by WM volumetric, relaxometry and diffusion tensor imaging studies. A potentially more specific measure of myelin content, termed myelin water fraction (MWF), could provide improved sensitivity to myelin alteration in autism.Method We performed a cross-sectional imaging study that compared 14 individuals with autism and 14 age- and IQ-matched controls. T1 relaxation times (T1), T2 relaxation times (T2) and MWF values were compared between autistic subjects, diagnosed using the Autism Diagnostic Interview – Revised (ADI-R), with current symptoms assessed using the Autism Diagnostic Observation Schedule (ADOS) and typical healthy controls. Correlations between T1, T2 and MWF values with clinical measures [ADI-R, ADOS, and the Autism Quotient (AQ)] were also assessed.Results Individuals with autism showed widespread WM T1 and MWF differences compared to typical controls. Within autistic individuals, worse current social interaction skill as measured by the ADOS was related to reduced MWF although not T1. No significant differences or correlations with symptoms were observed with respect to T2.Conclusions Autistic individuals have significantly lower global MWF and higher T1, suggesting widespread alteration in tissue microstructure and biochemistry. Areas of difference, including thalamic projections, cerebellum and cingulum, have previously been implicated in the disorder; however, this is the first study to specifically indicate myelin alteration in these regions.

KW - Autism

KW - brain connectivity

KW - brain development

KW - human brain imaging

KW - myelin

KW - white matter

UR - http://www.scopus.com/inward/record.url?scp=84927695839&partnerID=8YFLogxK

U2 - 10.1017/S0033291714001858

DO - 10.1017/S0033291714001858

M3 - Article

AN - SCOPUS:84927695839

SN - 0033-2917

VL - 45

SP - 795

EP - 805

JO - Psychological Medicine

JF - Psychological Medicine

IS - 4

ER -