Data Sheet 6_Attenuated sensorimotor hemodynamic responses and altered cortical dynamics during passive proprioceptive-related stimulation after stroke: a multidimensional fNIRS study.docx

Directed connectivity during prestimulus, stimulation, and recovery phases was assessed using a sliding-window multivariate autoregressive model with partial directed coherence (PDC). Recovery-phase dynamics were further quantified using sample entropy, mean multiscale entropy, recurrence rate (RR), determinism (DET), and mean diagonal line length (Lmean).</p>Results<p>A total of 62 participants, including 30 patients with stroke and 32 healthy controls, underwent a passive thumb movement task during fNIRS recording.

Conventional HbO analysis showed that between-group differences were mainly confined to the left sensorimotor cortex, where the stroke group differed significantly from healthy controls in AUC (p = 0.023), peak amplitude (p = 0.003), and recovery slope (p = 0.018). No other ROI showed significant between-group differences, although marginal trends were observed in the right prefrontal and right sensorimotor cortices. Latent state analysis identified six states.

Healthy controls more frequently occupied State 1 and State 5, whereas the stroke group more frequently occupied State 3 and State 6, and showed longer MDT in State 2 and State 3. Directed connectivity analysis revealed phase-dependent shifts in both groups, with the stroke group showing stronger prefrontal–sensorimotor reorganization across prestimulus, stimulation, and recovery phases. Recovery-phase complexity analysis demonstrated significantly higher global RR, DET, and Lmean in the stroke group, whereas sample entropy and mean multiscale entropy did not remain significant after correction.

ROI-level complexity differences did not survive multiple-comparison correction.</p>Conclusion<p>Abnormal proprioceptive processing after stroke is characterized not only by altered local activation, but also by dynamic state shifts, phase-specific reorganization of information flow, and increased regularity with reduced flexibility during recovery.</p>