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Background Poststroke depression (PSD) is related to adverse functional and cognitive prognosis in stroke patients. The participation of kynurenine pathway metabolites in depression has been previously proposed; however, there are few studies on its role in PSD and disability in stroke. Objective To investigate if there is a correlation between serum kynurenines levels with poststroke anxiety and depression symptoms and disability scales. Methods A cross-sectional case-control study was conducted in patients with first stroke, of >1 month and Results Sixty patients were included; significant depressive symptoms were found in 63% of the cases; a significant and positive correlation was obtained between levels of 3-hydroxykynurenine (3-HK) with HADS-T ( r = 0.30, P = .025) and HADS-D ( r = 0.28, P = .039). Depressed patients showed significantly higher levels of 3HK ( P = .048) and KYNA ( P = .0271) than nondepressed patients; the 3HK levels were inversely correlated with functional scales: Barthel index ( r = −0.31, P = .02), FIM ( r = −0.40, P = .01); in addition, serum 3HK levels were significantly higher in patients with poor sleep quality ( P = .0190). Conclusions Serum Kyns show correlation with the presence and severity of depressive symptoms and with the disability and sleep quality. Kyns may be a potential marker of depression risk and disability in stroke in future.

Stroke is a leading cause of motor disability worldwide. Upper limb rehabilitation is particularly challenging since approximately 35% of patients recover significant hand function after 6 months of the stroke’s onset. Therefore, new therapies, especially those based on brain-computer interfaces (BCI) and robotic assistive devices, are currently under research. Electroencephalography (EEG) acquired brain rhythms in alpha and beta bands, during motor tasks, such as motor imagery/intention (MI), could provide insight of motor-related neural plasticity occurring during a BCI intervention. Hence, a longitudinal analysis of subacute stroke patients’ brain rhythms during a BCI coupled to robotic device intervention was performed in this study. Data of 9 stroke patients were acquired across 12 sessions of the BCI intervention. Alpha and beta event-related desynchronization/synchronization (ERD/ERS) trends across sessions and their association with time since stroke onset and clinical upper extremity recovery were analyzed, using correlation and linear stepwise regression, respectively. More EEG channels presented significant ERD/ERS trends across sessions related with time since stroke onset, in beta, compared to alpha. Linear models implied a moderate relationship between alpha rhythms in frontal, temporal, and parietal areas with upper limb motor recovery and suggested a strong association between beta activity in frontal, central, and parietal regions with upper limb motor recovery. Higher association of beta with both time since stroke onset and upper limb motor recovery could be explained by beta relation with closed-loop communication between the sensorimotor cortex and the paralyzed upper limb, and alpha being probably more associated with motor learning mechanisms. The association between upper limb motor recovery and beta activations reinforces the hypothesis that broader regions of the cortex activate during movement tasks as a compensatory mechanism in stroke patients with severe motor impairment. Therefore, EEG across BCI interventions could provide valuable information for prognosis and BCI cortical activity targets.

Objective. This study assesses upper limb recovery prognosis after stroke with solely physiological information, which can provide an objective estimation of recovery. Approach. Clinical recovery was forecasted using EEG-derived Event-Related Desynchronization/Synchronization and coherence, in addition to Transcranial Magnetic Stimulation elicited motor-evoked potentials and upper limb grip and pinch strength. A Regression Tree Ensemble predicted clinical recovery of a stroke database (n = 10) measured after a two-month intervention with the Fugl-Meyer Assessment for the Upper Extremity (FMA-UE) and the Action Research Arm Test (ARAT). Main results. There were no significant differences between predicted and actual outcomes with FMA-UE (p = 0.29) and ARAT (p = 0.5). Median prediction error for FMA-UE and ARAT were of 0.3 (IQR = 6.2) and 3.4 (IQR = 9.4) points, respectively. Predictions with the most pronounced errors were due to an underestimation of high upper limb recovery. The best features for FMA-UE prediction included mostly beta activity over the sensorimotor cortex. Best ARAT prediction features were cortical beta activity, corticospinal tract integrity of the unaffected hemisphere, and upper limb strength. Significance. Results highlighted the importance of measuring cortical activity related to motor control processes, the unaffected hemisphere’s integrity, and upper limb strength for prognosis. It was also implied that stroke upper limb recovery prediction is feasible using solely physiological variables with a Regression Tree Ensemble, which can also be used to analyze physiological relationships with recovery.

Introduction Brain injuries are one of the leading causes of disability worldwide. It is estimated that nearly half of patients who develop severe sequelae will continue with a chronic severe disability despite having received an appropriate rehabilitation program. For more than 3 decades, there has been a worldwide effort to investigate the possibility of pharmacologically stimulating the neuroplasticity process for enhancing the recovery of these patients. Objective The objective of this article is to make a critical and updated review of the available evidence that supports the positive effect of different drugs on the recovery from brain injury. Method To date, there have been several clinical trials that tested different drugs that act on different neurotransmitter systems: catecholaminergic, cholinergic, serotonergic, and glutamatergic. There is both basic and clinical evidence that may support some positive effect of these drugs on motor, cognitive, and language skills; however, only few of the available studies are of sufficient methodological quality (placebo controlled, randomized, blinded, multicenter, etc) to make solid conclusions about their beneficial effects. Conclusions Currently, the pharmacological stimulation of neuroplasticity still does not have enough scientific evidence to make a systematic therapeutic recommendation for all patients, but it certainly is a feasible and very promising field for future research.