In Brain research
BACKGROUND AND PURPOSE : Patients with post stroke cognitive impairment (PSCI) frequently show changes in brain functional connectivity (FC). However, the underlying neurobiological mechanism of PSCI remains unclear. This study first applied degree centrality (DC) analysis to investigate the intrinsic dysconnectivity pattern of the brain in PSCI patients, as well as to explore the relationship between these changes and cognitive function.
METHODS : Resting-state functional magnetic resonance imaging (rs-fMRI) scanning was performed on all participants, including those with PSCI (n=20), stroke with no cognitive impairment (NPSCI, n=15), and healthy controls (HC, n=29). DC values were used to identify differences in FC among the three groups. The relationship between abnormal DC values and cognitive function was examined.
RESULTS : PSCI and NPSCI had significantly higher DC values in the right parahippocampal gyrus (PhG) in comparison with HC (p＜0.05). In addition, DC values of the right PhG showed a negative correlation with MoCA scores (r = -0.405, p = 0.001), the Auditory Verbal Learning Test (AVLT; r = -0.278, p = 0.026), Rey-Osterrieth Complex Figure Test-Delayed Recall (RCFT-DR; r = -0.250, p = 0.046), Symbol Digit Modality Test (SDMT; r = -0.385, p = 0.002), Boston Naming Test (BNT; r = -0.402, p = 0.001) and Animal Fluency Test (AFT; r = -0.395, p = 0.001). However, DC was significantly positively correlated with the Trail Making Test (TMT-A; r = 0.347, p = 0.005) and TMT-B (r = 0.294, p = 0.019).
CONCLUSIONS : DC values were increased in the right PhG following a mild subcortical stroke. DC values in the PhG were negatively correlated with cognitive function, which may indicate brain nodes reorganization.
Min Yan, Liu Chang, Zuo Lijun, Wang Yongjun, Li Zixiao
cognitive impairment, degree centrality, rs-fMRI, subcortical stroke