Association of Arterial Spin Labeling Parameters With Cognitive Decline, Vascular Events, and Mortality in a Memory-Clinic Sample

Effects of computerized cognitive training on functional brain networks in patients with vascular cognitive impairment and no dementia

AIMS

Previous neuroimaging studies of vascular cognitive impairment, no dementia (VCIND), have reported functional alterations, but far less is known about the effects of cognitive training on functional connectivity (FC) of intrinsic connectivity networks (ICNs) and how they relate to intervention-related cognitive improvement. This study provides comprehensive research on the changes in intra- and inter-brain functional networks in patients with VCIND who received computerized cognitive training, with a focus on the underlying mechanisms and potential therapeutic strategies.

METHODS

We prospectively collected 60 patients with VCIND who were randomly divided into the training group (N = 30) receiving computerized cognitive training and the control group (N = 30) receiving fixed cognitive training. Functional MRI scans and cognitive assessments were performed at baseline, at the 7-week training, and at the 6-month follow-up. Utilizing templates for ICNs, the study employed a linear mixed model to compare intra- and inter-network FC changes between the two groups. Pearson correlation was applied to calculate the relationship between FC and cognitive function.

RESULTS

We found significantly decreased intra-network FC within the default mode network (DMN) following computerized cognitive training at Month 6 (p = 0.034), suggesting a potential loss of functional specialization. Computerized training led to increased functional coupling between the DMN and sensorimotor network (SMN) (p = 0.01) and between the language network (LN) and executive control network (ECN) at Month 6 (p < 0.001), indicating compensatory network adaptations in patients with VCIND. Notably, the intra-LN exhibited enhanced functional specialization after computerized cognitive training (p = 0.049), with significant FC increases among LN regions, which correlated with improvements in neuropsychological measures (p < 0.05), emphasizing the targeted impact of computerized cognitive training on language abilities.

CONCLUSIONS

This study provides insights into neuroplasticity and adaptive changes resulting from cognitive training in patients with VCIND, with implications for potential therapeutic strategies.

Causality between cognitive performance and cardiovascular disease: A bidirectional Mendelian randomization study

BACKGROUND

Growing evidence points to a connection between cardiovascular disease and cognitive impairment. These observational study findings, however, were not all uniform, and some did not discover a link like this. Investigating the causal link between cognitive impairment and cardiovascular disease is vital.

METHOD

Using publicly available genome-wide association study (GWAS) summary datasets and stringent screening instrumental variables, we carried out a bidirectional Mendelian randomization study. To investigate the causality between cardiovascular disease and cognitive impairment, three different MR techniques-inverse variance weighted (IVW), MR-Egger, and weighted median-as well as various sensitivity analyses-Cochran's Q, ivw_radial, leave-one-out (LOO), MR-Egger intercept, and MR-PRESSO-were used.

RESULTS

The causal impact of genetically predicted cognitive performance on hypertension, atrial fibrillation, heart failure, coronary atherosclerosis, coronary artery disease, and myocardial infarction was detected in the forward MR analysis, but not stroke or any subtypes. We only discover the causal effects of hypertension, any stroke, and its subtypes (ischemic and small vessel stroke) on cognitive performance in the reverse MR analysis.

CONCLUSION

This MR analysis offers proof of a causal link between cognitive impairment and elevated cardiovascular disease risk. Our research emphasizes the value of cognitively impaired patients being screened for cardiovascular disease, which may offer fresh perspectives on cardiovascular disease prevention.