Brain computer interface(BCI)is a rapidly developing rehabilitation technology in recent years, which has been gradually used for cognitive rehabilitation of stroke patients.BCI can activate brain regions related to cognition to a greater extent through motor imagery and neural feedback technology, promote functional connectivity between brain regions, and ameliorate cognitive impairment after stroke.This paper summarized the mechanisms involved in BCI promoting cognitive rehabilitation and current applications of BCI in post-stroke cognitive impairment, and identifies the shortcomings of BCI in the treatment of post-stroke cognitive impairment, in order to provide insight for the research and clinical practice of BCI in post-stroke cognitive rehabilitation.

Objective: To investigate the association between sleep duration and frailty among people aged 50 years and over. Methods: Cross-sectional data was collected from the first wave of World Health Organization Study on global AGEing and adult health in China. Frailty index was constructed on the proportion of deficits, out of the 40 variables. A two-level (individual level and community level) linear model was performed to identify the related factors on frailty. All the models were stratified by age, gender, residence (urban/rural). Restricted cubic spline was performed to graphically evaluate the dose-response association between self-reported sleep duration and frailty. Results: A total of 13 175 individuals aged 50 years and over participated in this study. Without adjusting on any confounding factors, shorter or longer sleep duration significantly increased the risk of weakness compared with normal sleep time (OR=2.05, 95%CI: 1.71-2.44; OR=1.35, 95%CI: 1.12-1.63). After adjusting for confounding factors such as gender, age, residence, education, family assets, vegetable, smoking, drinking and physical activity, a positive association between short sleep duration and frailty was noticed compared with normal sleep time (aOR=1.60, 95%CI: 1.27-2.01). The results of stratified analysis on sex, age and urban and rural areas showed that, after adjusting for gender, age, residence, education level, family assets, intake of vegetables and fruits, smoking, drinking and physical activity, only shorter sleep duration was positively correlated with the risk of weakness. In addition, among people aged 65 years and over, adjusted for confounding factors, the risk of weakness increased by 91%, compared with normal sleep time (aOR=1.91, 95%CI: 1.46-2.49). The dose-response curve also showed that the sleep duration and frailty present an approximate "U" shaped relationship. Conclusion Short sleep duration might be associated with frailty.