Hewitt, Manuel

[["dc.bibliographiccitation.firstpage","509"],["dc.bibliographiccitation.journal","NeuroImage"],["dc.bibliographiccitation.lastpage","517"],["dc.bibliographiccitation.volume","124"],["dc.contributor.author","Meincke, Jonna"],["dc.contributor.author","Hewitt, Manuel"],["dc.contributor.author","Batsikadze, Giorgi"],["dc.contributor.author","Liebetanz, David"],["dc.date.accessioned","2018-11-07T10:21:46Z"],["dc.date.available","2018-11-07T10:21:46Z"],["dc.date.issued","2016"],["dc.description.abstract","Background: Although neuronavigation is increasingly used for optimizing coil positioning, the inter-session reliability of hotspot location remains unsatisfactory, probably due to the variability of motor evoked potentials (MEPs) and residual investigator bias. Purpose: To increase the reliability and accuracy of hotspot location we introduce a novel automated hotspot-hunting procedure (AHH). Methods: AHH is based on resting motor thresholds (RMTs) instead of MEP amplitudes. By combining robotic coil positioning with a closed loop target search algorithm AHH runs independently from the investigator. AHH first identifies all targets with an RMT below a defined intensity of stimulator output (MEP-positive) and then locates the motor hotspot of a target muscle by measuring RMTs at all identified MEP-positive targets. Results were compared to robotic MEP amplitude TMS mapping (MAM) using a 7 x 7 predefined target grid and suprathreshold intensities and manual hotspot search (MHS). Sequence of stimulation was randomized from pulse to pulse in AHH and MAM. Each procedure was tested in 8 subjects. Results: Inter-session CoG shift was significantly reduced with AHH (1.4 mm (SEM: 0.4)) as compared to MAM (7.0 mm (SEM: 1.8)) (p=0.018) and MHS (9.6 mm (SEM: 2.2)) (p=0.007). No statistical difference was observed between MAM and MHS. RMTs were reliable between sessions. Conclusion: Our method represents the first fully automated, i.e. investigator-independent, TMS hotspot-hunting procedure. Measuring RMTs instead of MEP amplitudes leads to significantly increased accuracy and reliability of CoG locations. Moreover, by assessing thresholds AHH is the first procedure to fulfill the original hotspot definition. (C) 2015 Elsevier Inc. All rights reserved."],["dc.identifier.doi","10.1016/j.neuroimage.2015.09.013"],["dc.identifier.isi","000366646700047"],["dc.identifier.pmid","26385012"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/42150"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Academic Press Inc Elsevier Science"],["dc.relation.issn","1095-9572"],["dc.relation.issn","1053-8119"],["dc.title","Automated TMS hotspot-hunting using a closed loop threshold-based algorithm"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","79"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Restorative Neurology and Neuroscience"],["dc.bibliographiccitation.lastpage","95"],["dc.bibliographiccitation.volume","34"],["dc.contributor.author","Schmalfuss, Leonie"],["dc.contributor.author","Rupp, R."],["dc.contributor.author","Tuga, Michele Rene"],["dc.contributor.author","Kogut, A."],["dc.contributor.author","Hewitt, M."],["dc.contributor.author","Meincke, Jonna"],["dc.contributor.author","Klinker, Florian"],["dc.contributor.author","Duttenhoefer, W."],["dc.contributor.author","Eck, U."],["dc.contributor.author","Mikut, Ralf"],["dc.contributor.author","Reischl, Markus"],["dc.contributor.author","Liebetanz, David"],["dc.date.accessioned","2018-11-07T10:21:21Z"],["dc.date.available","2018-11-07T10:21:21Z"],["dc.date.issued","2016"],["dc.description.abstract","Purpose: Providing mobility solutions for individuals with tetraplegia remains challenging. Existing control devices have shortcomings such as varying or poor signal quality or interference with communication. To overcome these limitations, we present a novel myoelectric auricular control system (ACS) based on bilateral activation of the posterior auricular muscles (PAMs). Methods: Ten able-bodied subjects and two individuals with tetraplegia practiced PAM activation over 4 days using visual feedback and software-based training for 1 h/day. Initially, half of these subjects were not able to voluntarily activate their PAMs. This ability was tested with regard to 8 parameters such as contraction rate, lateralized activation, wheelchair speed and path length in a virtual obstacle course. In session 5, all subjects steered an electric wheelchair with the ACS. Results: Performance of all subjects in controlling their PAMs improved steadily over the training period. By day 5, all subjects successfully generated basic steering commands using the ACS in a powered wheelchair, and subjects with tetraplegia completed a complex real-world obstacle course. This study demonstrates that the ability to activate PAM on both sides together or unilaterally can be learned and used intuitively to steer a wheelchair. Conclusions: With the ACS we can exploit the untapped potential of the PAMs by assigning them a new, complex function. The inherent advantages of the ACS, such as not interfering with oral communication, robustness, stability over time and proportional and continuous signal generation, meet the specific needs of wheelchair users and render it a realistic alternative to currently available assistive technologies."],["dc.identifier.doi","10.3233/RNN-150579"],["dc.identifier.isi","000368632700007"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/42066"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Ios Press"],["dc.relation.issn","1878-3627"],["dc.relation.issn","0922-6028"],["dc.title","Steer by ear: Myoelectric auricular control of powered wheelchairs for individuals with spinal cord injury"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]