03884nas a2200205   4500008004100000022001400041245016800055210006900223260001600292520308600308100001703394700002003411700002703431700002503458700001603483700001603499700002303515700002403538856011603562       2026                        eng d  a2692-820500aBilateral Mechanoreception Discrimination based on Bihemispheric Somatosensory Response Patterns is Associated with Proprioception and Motor Function After Stroke.0 aBilateral Mechanoreception Discrimination based on Bihemispheric  c2026 Jul 273 a<p><b>OBJECTIVES: </b>Stroke commonly impairs proprioception and motor function, yet the cortical sensory processes underlying these impairments remain poorly understood. Prior electrophysiological studies have primarily focused on the average magnitude of unilateral cortical sensory responses to vibration, potentially overlooking distributed and trial-to-trial features of sensory processing that may be functionally relevant to proprioceptive processing and motor performance. We therefore aimed to characterize bilateral cortical sensory responses to determine their relationships with proprioceptive and motor function.</p><p><b>METHODS: </b>EEG was recorded from forty-six individuals with chronic stroke during a rapid, passive, vibrotactile stimulation paradigm applied to the left and right fingertips. Somatosensory evoked potentials (SEPs) and event-related desynchronization (ERD) were quantified. Finger proprioceptive performance was assessed using a passive, robotic, finger crossing identification task, while motor function was evaluated using the Box and Block Test, Fugl-Meyer Assessment, and Nine Hole Peg Test. Associations with function were assessed using (i) unilateral sensory response magnitude at the contralateral parietal cortex and (ii) somatosensory decoder performance, defined as the accuracy with which a decoder identified the location of the stimulated hand (i.e. paretic vs. non-paretic) from combined bihemispheric response patterns. The association between these responses and proprioceptive ability and motor function was assessed. These associations were further evaluated jointly across multiple motor function measures using an exploratory analysis leveraging nonlinear dimensionality reduction and clustering.</p><p><b>RESULTS: </b>Vibrotactile stimulation of the paretic hand elicited ipsilesional SEP and ERD that were reduced in magnitude compared to stimulation of the non-paretic hand. Both decreased SEP magnitude and reduced sensory decoder performance were associated with greater finger proprioceptive error. Unlike unilateral responses, the somatosensory decoder's performance was also strongly associated with motor function, explaining approximately 22.5% of the variance in motor performance. Dimensionality reduction and clustering across multiple motor assessment scores showed distinct subgroups, that showed significant differences in sensory decoding.</p><p><b>CONCLUSIONS: </b>The hemispheric distribution and discriminability of cortical sensory responses are functionally relevant markers of sensorimotor integrity after stroke. Assessing relative lateralization of somatosensory responses for each hand, rather than the magnitude of dominant contralateral responses alone, may better capture the reliability of sensory processing after stroke, as well as the distributed cortical reorganization supporting sensorimotor function. These findings support the potential value of a novel decoding-based neurophysiological measure for sensory-driven rehabilitation, biomarker development, and patient stratification.</p>1 aGupta, Disha1 aFarrens, Andria1 aGarcia-Fernandez, Luis1 aRojas, Raymond, Diaz1 aChan, Vicky1 aPerry, Joel1 aWolbrecht, Eric, T1 aReinkensmeyer, Dave  uhttps://www.neurotechcenter.org/publications/2026/bilateral-mechanoreception-discrimination-based-bihemispheric02169nas a2200301   4500008004100000022001400041245015400055210006900209260001300278300000800291490000900299520119500308653000901503653002101512653001101533653001101544653000901555653001601564653001301580653001101593653002601604100002701630700001901657700002301676700002801699700001701727856012301744       2024                        eng d  a2694-060400aMultidimensional feature analysis shows stratification in robotic-motor-training gains based on the level of pre-training motor impairment in stroke.0 aMultidimensional feature analysis shows stratification in roboti  c2024 Jul  a1-50 v20243 a<p>Stroke involves heterogeneity in injury and ongoing endogenous recovery, which are seldom stratified before testing post-stroke robot assisted motor training (RAMT). Pretraining variations, especially sensory-motor differences may also affect the gains achieved from the RAMT. Moreover, one assessment test may not effectively characterize the baseline sensory-motor status or the RAMT gains. Pre-therapy stratification may help personalize therapy and increase therapy gains. Towards this goal, we propose a data-driven approach to assess multiple functional scores with t-distributed stochastic neighbor embedding and affinity propagation clustering, both for pre-therapy and RAMT gains. Data included behavioral scores from 27 people with chronic stroke who underwent RAMT for finger movement. Three clusters were observed at start-of-therapy (SoT), concurrent with the overall impairment level. Four clusters were observed for the RAMT gains, indicating specific improvements. The SoT clusters showed agreement with the RAMT gain clusters, suggesting that the pre-therapy state, assessed across multiple domains, could be useful in guiding RAMT interventions to improve outcomes.</p>10aAged10aCluster Analysis10aFemale10aHumans10aMale10aMiddle Aged10aRobotics10aStroke10aStroke Rehabilitation1 aRueda-Parra, Sebastian1 aPerry, Joel, C1 aWolbrecht, Eric, T1 aReinkensmeyer, David, J1 aGupta, Disha  uhttps://www.neurotechcenter.org/publications/2024/multidimensional-feature-analysis-shows-stratification-robotic-motor