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(1) Improving upper limb function is essential for people with tetraplegia. Although promising, technology-assisted upper limb training is understudied in this population. This article describes its implementation in a Swiss spinal cord injury rehabilitation centre and reports on the observed changes. (2) A retrospective evaluation of clinical data from January 2018 to June 2020 examined patient characteristics, training parameters, goal-setting practices, goal achievement, and changes in muscle strength over the course of technology-assisted upper limb training. (3) Data analysis included 61 individuals, 68.9% of whom had a spinal cord injury. The ArmeoSpring was the most frequently used device. The typical treatment regimen was three 25 min sessions per week, with evaluations approximately every six weeks. The 1:1 sessions, delivered by specialised staff, focused primarily on improving shoulder movement and the ability to eat and drink. Functional goals were set using a grid. Performance on selected goals in the areas of 'body functions' and 'activities & participation' as well as muscle strength, increased over the course of training. (4) The ArmeoSpring has broad applicability. Despite the observed improvements, the isolated effect of technology-assisted upper limb training cannot be concluded due to the lack of a control group and various concurrent interventions. [ABSTRACT FROM AUTHOR]

It has been proposed that a form of cortical reorganization (changes in functional connectivity between brain areas) can be assessed with resting-state (rs) functional MRI (fMRI). Here, we report a longitudinal data set collected from 19 patients with subcortical stroke and 11 controls. Patients were imaged up to five times over 1 year. We found no evidence, using rs-fMRI, for longitudinal poststroke cortical connectivity changes despite substantial behavioral recovery. These results could be construed as questioning the value of resting-state imaging. Here, we argue instead that they are consistent with other emerging reasons to challenge the idea of motor-recovery-related cortical reorganization poststroke when conceived of as changes in connectivity between cortical areas. [ABSTRACT FROM AUTHOR]

Objective: Patients with chronic stroke have been shown to have failure to release interhemispheric inhibition (IHI) from the intact to the damaged hemisphere before movement execution (premovement IHI). This inhibitory imbalance was found to correlate with poor motor performance in the chronic stage after stroke and has since become a target for therapeutic interventions. The logic of this approach, however, implies that abnormal premovement IHI is causal to poor behavioral outcome and should therefore be present early after stroke when motor impairment is at its worst. To test this idea, in a longitudinal study, we investigated interhemispheric interactions by tracking patients' premovement IHI for one year following stroke.Methods: We assessed premovement IHI and motor behavior five times over a 1-year period after ischemic stroke in 22 patients and 11 healthy participants.Results: We found that premovement IHI was normal during the acute/subacute period and only became abnormal at the chronic stage; specifically, release of IHI in movement preparation worsened as motor behavior improved. In addition, premovement IHI did not correlate with behavioral measures cross-sectionally, whereas the longitudinal emergence of abnormal premovement IHI from the acute to the chronic stage was inversely correlated with recovery of finger individuation.Interpretation: These results suggest that interhemispheric imbalance is not a cause of poor motor recovery, but instead might be the consequence of underlying recovery processes. These findings call into question the rehabilitation strategy of attempting to rebalance interhemispheric interactions in order to improve motor recovery after stroke. Ann Neurol 2019;85:502-513. [ABSTRACT FROM AUTHOR]

Following a stroke, mirror movements are unintended movements that appear in the non-paretic hand when the paretic hand voluntarily moves. Mirror movements have previously been linked to overactivation of sensorimotor areas in the non-lesioned hemisphere. In this study, we hypothesized that mirror movements might instead have a subcortical origin, and are the by-product of subcortical motor pathways upregulating their contributions to the paretic hand. To test this idea, we first characterized the time course of mirroring in 53 first-time stroke patients, and compared it to the time course of activities in sensorimotor areas of the lesioned and non-lesioned hemispheres (measured using functional MRI). Mirroring in the non-paretic hand was exaggerated early after stroke (Week 2), but progressively diminished over the year with a time course that parallelled individuation deficits in the paretic hand. We found no evidence of cortical overactivation that could explain the time course changes in behaviour, contrary to the cortical model of mirroring. Consistent with a subcortical origin of mirroring, we predicted that subcortical contributions should broadly recruit fingers in the non-paretic hand, reflecting the limited capacity of subcortical pathways in providing individuated finger control. We therefore characterized finger recruitment patterns in the non-paretic hand during mirroring. During mirroring, non-paretic fingers were broadly recruited, with mirrored forces in homologous fingers being only slightly larger (1.76 times) than those in non-homologous fingers. Throughout recovery, the pattern of finger recruitment during mirroring for patients looked like a scaled version of the corresponding control mirroring pattern, suggesting that the system that is responsible for mirroring in controls is upregulated after stroke. Together, our results suggest that post-stroke mirror movements in the non-paretic hand, like enslaved movements in the paretic hand, are caused by the upregulation of a bilaterally organized subcortical system. [ABSTRACT FROM AUTHOR]

Background: Fifty percent of all stroke survivors remain with functional impairments of their upper limb. While there is a need to improve the effectiveness of rehabilitative training, so far no new training approach has proven to be clearly superior to conventional therapy. As training with rewarding feedback has been shown to improve motor learning in humans, it is hypothesized that rehabilitative arm training could be enhanced by rewarding feedback. In this paper, we propose a trial protocol investigating rewards in the form of performance feedback and monetary gains as ways to improve effectiveness of rehabilitative training.Methods: This multicentric, assessor-blinded, randomized controlled trial uses the ArmeoSenso virtual reality rehabilitation system to train 74 first-ever stroke patients (< 100 days post stroke) to lift their impaired upper limb against gravity and to improve the workspace of the paretic arm. Three sensors are attached to forearm, upper arm, and trunk to track arm movements in three-dimensional space while controlling for trunk compensation. Whole-arm movements serve as input for a therapy game. The reward group (n = 37) will train with performance feedback and contingent monetary reward. The control group (n = 37) uses the same system but without monetary reward and with reduced performance feedback. Primary outcome is the change in the hand workspace in the transversal plane. Standard clinical assessments are used as secondary outcome measures.Discussion: This randomized controlled trial will be the first to directly evaluate the effect of rewarding feedback, including monetary rewards, on the recovery process of the upper limb following stroke. This could pave the way for novel types of interventions with significantly improved treatment benefits, e.g., for conditions that impair reward processing (stroke, Parkinson's disease).Trial Registration: ClinicalTrials.gov, ID: NCT02257125 . Registered on 30 September 2014. [ABSTRACT FROM AUTHOR]

Feedback on motor performance activates the striatum and boosting ventral striatum activation with rewarding feedback during motor training supports the consolidation of the learned skill. Aging is associated with changes of the reward system, including striatal and extrastriatal loss of dopamine receptors. How these changes interact with the blood oxygenation level dependent (BOLD) response is, however, not yet fully understood. While it is known that reward prediction and reward-based decision-making differ between young and elderly healthy adults, the influence of age on the processing of rewarding feedback on motor performance have not been investigated so far. Nineteen young (26.42 ± 2.84 years) and 18 elderly (65.39 ± 6.40 years) healthy adults performed an arc-tracking task including performance feedback linked to a monetary reward after half of the trials, while undergoing functional magnetic resonance imaging (fMRI). The BOLD effect was compared in three predefined regions of interest: Ventral and dorsal striatum plus primary motor cortex. Our study demonstrates differences in the processing of motor performance related reward between young and elderly healthy adults. While both groups earned similar amounts of money linked to their own performance, the ventral striatal response to the rewarding feedback was higher in the older group. Deficient prediction about the rewarding feedback, a higher motivational status or compensation for a reduced number of dopamine receptors in the elderly might be possible explanations. How this interacts with the reward-induced improvement of motor skill consolidation, as observed in young subjects, has to be clarified. [ABSTRACT FROM AUTHOR]