Microstructure of the superior longitudinal fasciculus predicts stimulation-induced interference with on-line motor control

Type of publication:  Artikel
Zeitschrift: Neuroimage
Band: accepted for publication
Jahr: 2015
Abriss: A cortical visuomotor reaching network, comprising the medial intraparietal sulcus (mIPS) and the dorsal premotor area (PMd), encodes the sensorimotor transformations required for the on-line control of reaching movements. How information is transmitted between these two regions and which pathways are involved, is less clear. Here, we use a multimodal approach combining repetitive transcranial magnetic stimulation (rTMS) and diffusion tensor imaging (DTI) to investigate whether structural connectivity in the ‘reaching’ circuit is associated to variations in the ability to control and update a movement. We induced a transient disruption of the neural processes underlying on-line motor adjustments by applying 1 Hz rTMS over the mIPS. After the stimulation protocol, participants globally showed a reduction of the number of corrective trajectories during a reaching task that included unexpected visual perturbations. A voxel-based analysis revealed that participants exhibiting higher fractional anisotropy (FA) in the second branch of the superior longitudinal fasciculus (SLF II) suffered less rTMS-induced behavioral impact. These results indicate that the microstructural features of the white matter bundles within the parieto-frontal ‘reaching’ circuit play a prominent role when action reprogramming is interfered. Moreover, our study suggests that the structural alignment and cohesion of the white matter tracts might be used as a predictor to characterize the extent of motor impairments.
Autoren: Rodriguez-Herreros, Borja
Amengual, Juliá L.
Gurtubay, Ane
Richter, Lars
Jauer, Philipp
Erdmann, Christian
Schweikard, Achim
López-Moliner, Juan
Rodriguez-Fornells, Antoni
Münte, Thomas F.