@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} } @article{SaulinHornLotzeetal.2022, author = {Saulin, Anne and Horn, Ulrike and Lotze, Martin and Kaiser, Jochen and Hein, Grit}, title = {The neural computation of human prosocial choices in complex motivational states}, series = {NeuroImage}, volume = {247}, journal = {NeuroImage}, doi = {10.1016/j.neuroimage.2021.118827}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-265852}, year = {2022}, abstract = {Motives motivate human behavior. Most behaviors are driven by more than one motive, yet it is unclear how different motives interact and how such motive combinations affect the neural computation of the behaviors they drive. To answer this question, we induced two prosocial motives simultaneously (multi-motive condition) and separately (single motive conditions). After the different motive inductions, participants performed the same choice task in which they allocated points in favor of the other person (prosocial choice) or in favor of themselves (egoistic choice). We used fMRI to assess prosocial choice-related brain responses and drift diffusion modeling to specify how motive combinations affect individual components of the choice process. Our results showed that the combination of the two motives in the multi-motive condition increased participants' choice biases prior to the behavior itself. On the neural level, these changes in initial prosocial bias were associated with neural responses in the bilateral dorsal striatum. In contrast, the efficiency of the prosocial decision process was comparable between the multi-motive and the single-motive conditions. These findings provide insights into the computation of prosocial choices in complex motivational states, the motivational setting that drives most human behaviors .}, language = {en} }