@article{Gonzalez‐EscamillaMuthuramanReichetal.2019,
  author    = {Gonzalez-Escamilla, Gabriel and Muthuraman, Muthuraman and Reich, Martin M. and Koirala, Nabin and Riedel, Christian and Glaser, Martin and Lange, Florian and Deuschl, G{\"u}nther and Volkmann, Jens and Groppa, Sergiu},
  title     = {Cortical network fingerprints predict deep brain stimulation outcome in dystonia},
  series = {Movement Disorders},
  volume    = {34},
  journal   = {Movement Disorders},
  number    = {10},
  doi       = {10.1002/mds.27808},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-213532},
  pages     = {1536 -- 1545},
  year      = {2019},
  abstract  = {Background Deep brain stimulation (DBS) is an effective evidence-based therapy for dystonia. However, no unequivocal predictors of therapy responses exist. We investigated whether patients optimally responding to DBS present distinct brain network organization and structural patterns. Methods From a German multicenter cohort of 82 dystonia patients with segmental and generalized dystonia who received DBS implantation in the globus pallidus internus, we classified patients based on the clinical response 3 years after DBS. Patients were assigned to the superior-outcome group or moderate-outcome group, depending on whether they had above or below 70\% motor improvement, respectively. Fifty-one patients met MRI-quality and treatment response requirements (mean age, 51.3 ± 13.2 years; 25 female) and were included in further analysis. From preoperative MRI we assessed cortical thickness and structural covariance, which were then fed into network analysis using graph theory. We designed a support vector machine to classify subjects for the clinical response based on individual gray-matter fingerprints. Results The moderate-outcome group showed cortical atrophy mainly in the sensorimotor and visuomotor areas and disturbed network topology in these regions. The structural integrity of the cortical mantle explained about 45\% of the DBS stimulation amplitude for optimal response in individual subjects. Classification analyses achieved up to 88\% of accuracy using individual gray-matter atrophy patterns to predict DBS outcomes. Conclusions The analysis of cortical integrity, informed by group-level network properties, could be developed into independent predictors to identify dystonia patients who benefit from DBS.},
  language  = {en}
}
@article{DingSeusingNasseroleslamietal.2023,
  author    = {Ding, Hao and Seusing, Nelly and Nasseroleslami, Bahman and Anwar, Abdul Rauf and Strauss, Sebastian and Lotze, Martin and Grothe, Matthias and Groppa, Sergiu and Muthuraman, Muthuraman},
  title     = {The role of ipsilateral motor network in upper limb movement},
  series = {Frontiers in Physiology},
  volume    = {14},
  journal   = {Frontiers in Physiology},
  issn      = {1664-042X},
  doi       = {10.3389/fphys.2023.1199338},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-321805},
  year      = {2023},
  abstract  = {The execution of voluntary movements is primarily governed by the cerebral hemisphere contralateral to the moving limb. Previous research indicates that the ipsilateral motor network, comprising the primary motor cortex (M1), supplementary motor area (SMA), and premotor cortex (PM), plays a crucial role in the planning and execution of limb movements. However, the precise functions of this network and its interplay in different task contexts have yet to be fully understood. Twenty healthy right-handed participants (10 females, mean age 26.1 ± 4.6 years) underwent functional MRI scans while performing biceps brachii representations such as bilateral, unilateral flexion, and bilateral flexion-extension. Ipsilateral motor evoked potentials (iMEPs) were obtained from the identical set of participants in a prior study using transcranial magnetic stimulation (TMS) targeting M1 while employing the same motor tasks. The voxel time series was extracted based on the region of interest (M1, SMA, ventral PM and dorsal PM). Directed functinal connectivity was derived from the extracted time series using time-resolved partial directed coherence. We found increased connectivity from left-PMv to both sides M1, as well as right-PMv to both sides SMA, in unilateral flexion compared to bilateral flexion. Connectivity from left M1 to left-PMv, and left-SMA to right-PMd, also increased in both unilateral flexion and bilateral flexion-extension compared to bilateral flexion. However, connectivity between PMv and right-M1 to left-PMd decreased during bilateral flexion-extension compared to unilateral flexion. Additionally, during bilateral flexion-extension, the connectivity from right-M1 to right-SMA had a negative relationship with the area ratio of iMEP in the dominant side. Our results provide corroborating evidence for prior research suggesting that the ipsilateral motor network is implicated in the voluntary movements and underscores its involvement in cognitive processes such as movement planning and coordination. Moreover, ipsilateral connectivity from M1 to SMA on the dominant side can modulate the degree of ipsilateral M1 activation during bilateral antagonistic contraction.},
  language  = {en}
}