Interhemispheric motor networks are abnormal in patients with Gilles de la Tourette syndrome

TY - JOUR

T1 - Interhemispheric motor networks are abnormal in patients with Gilles de la Tourette syndrome

AU - Bäumer, Tobias

AU - Thomalla, Götz

AU - Kroeger, Johan

AU - Jonas, Melanie

AU - Gerloff, Christian

AU - Hummel, Friedhelm Christoph

AU - Müller-Vahl, Kirsten

AU - Schnitzler, Alfons

AU - Siebner, Hartwig Roman

AU - Orth, Michael

AU - Münchau, Alexander

N1 - © 2010 Movement Disorder Society.

PY - 2010/12/15

Y1 - 2010/12/15

N2 - Brain imaging has shown altered corpus callosum (CC) morphology in patients with Gilles de la Tourette syndrome (GTS). Yet it is unclear whether these morphological changes are associated with altered interhemispheric interactions. Here, we combined transcranial magnetic stimulation (TMS) with diffusion tensor magnetic resonance imaging (DTI) to explore functional and structural interhemispheric connections between the left and right motor hand areas. We studied 14 unmedicated GTS patients without psychiatric comorbidity (2 women, mean age 35.5 years) and 15 healthy volunteers (3 women, mean age 35 years). Left-to-right and right-to-left interhemispheric inhibitions (IHIs) were measured in hand muscles with TMS. In 13 GTS patients and all healthy controls, we measured fractional anisotropy (FA) with DTI to examine the relation between functional measures of interhemispheric connectivity as derived by TMS and structural properties of the CC region that carries fibers interconnecting both motor cortices. In GTS patients, left-to-right IHI was weaker than right-to-left IHI. Left-to-right IHI in GTS patients was also reduced compared with healthy controls. Voxel-based morphometric analysis revealed that FA in the motor region of the CC did not differ between groups. However, there was a significant interaction between groups and the relation between regional FA and left-to-right IHI in the motor region of the CC. A negative linear relation between FA and left-to-right IHI was present in control subjects but not in patients. Our combined TMS-DTI approach demonstrates abnormal functional interhemispheric connectivity in GTS accompanied by an altered structure-function relationship in the motor CC.

AB - Brain imaging has shown altered corpus callosum (CC) morphology in patients with Gilles de la Tourette syndrome (GTS). Yet it is unclear whether these morphological changes are associated with altered interhemispheric interactions. Here, we combined transcranial magnetic stimulation (TMS) with diffusion tensor magnetic resonance imaging (DTI) to explore functional and structural interhemispheric connections between the left and right motor hand areas. We studied 14 unmedicated GTS patients without psychiatric comorbidity (2 women, mean age 35.5 years) and 15 healthy volunteers (3 women, mean age 35 years). Left-to-right and right-to-left interhemispheric inhibitions (IHIs) were measured in hand muscles with TMS. In 13 GTS patients and all healthy controls, we measured fractional anisotropy (FA) with DTI to examine the relation between functional measures of interhemispheric connectivity as derived by TMS and structural properties of the CC region that carries fibers interconnecting both motor cortices. In GTS patients, left-to-right IHI was weaker than right-to-left IHI. Left-to-right IHI in GTS patients was also reduced compared with healthy controls. Voxel-based morphometric analysis revealed that FA in the motor region of the CC did not differ between groups. However, there was a significant interaction between groups and the relation between regional FA and left-to-right IHI in the motor region of the CC. A negative linear relation between FA and left-to-right IHI was present in control subjects but not in patients. Our combined TMS-DTI approach demonstrates abnormal functional interhemispheric connectivity in GTS accompanied by an altered structure-function relationship in the motor CC.

KW - Adult

KW - Anisotropy

KW - Brain Mapping

KW - Corpus Callosum

KW - Diffusion Magnetic Resonance Imaging

KW - Female

KW - Humans

KW - Image Processing, Computer-Assisted

KW - Male

KW - Middle Aged

KW - Motor Cortex

KW - Nerve Net

KW - Severity of Illness Index

KW - Tourette Syndrome

KW - Transcranial Magnetic Stimulation

U2 - 10.1002/mds.23418

DO - 10.1002/mds.23418

M3 - Journal article

C2 - 20960481

SN - 0885-3185

VL - 25

SP - 2828

EP - 2837

JO - Movement Disorders

JF - Movement Disorders

IS - 16

ER -