# Cognitive training reorganizes lateralization of fronto-parietal network in vascular cognitive impairment

## TL;DR

Cognitive training changes brain network lateralization in vascular cognitive impairment patients, improving memory and executive functions temporarily.

## Contribution

The study reveals how cognitive training reorganizes brain lateralization in vascular cognitive impairment patients.

## Key findings

- VCIND patients showed FPN lateralization similar to healthy adults at baseline.
- Cognitive training reduced FPN lateralization, improving executive and memory functions temporarily.
- Functional changes from training diminished after 6 months.

## Abstract

Vascular cognitive impairment no dementia (VCIND) represents cognitive deficits due to vascular causes, without meeting the criteria for dementia. Cognitive training has emerged as a safe and effective intervention for VCIND, though its underlying mechanisms remain obscure. This study investigates how subcortical VCIND and computerized cognitive training affect brain functional lateralization of the fronto-parietal network (FPN), whose functions are notably influenced by both VCIND and cognitive training. In a randomized, active-controlled design for VCIND patients, we assessed the resting-state functional lateralization index (LI) of the FPN and conducted neuropsychological assessments in VCIND training and control groups (n = 30 per group) at baseline, after a 7-week intervention and at a 6-month follow-up. A healthy older group (n = 30) only provided baseline data. At baseline, VCIND patients showed an FPN lateralization pattern similar to that of healthy older adults. However, a stronger right-lateralized interhemispheric heterotopic LI in FPN correlated with better memory performance only in healthy adults. After the intervention, only the VCIND training group exhibited reduced lateralization in FPN, shifting to a bilateral interhemispheric LI, with stronger leftward changes correlating with improved executive and memory functions. Notably, these changes disappeared at the 6-month follow-up. These findings suggest that subcortical VCIND modifies the relationship between FPN lateralization and cognitive functions, rather than altering the lateralization pattern itself. Short-term computerized cognitive training facilitates executive and memory functions by promoting hemispherical reorganizing of FPN and functional compensation, although the benefits may diminish over time.

Xinhu et al. reported that healthy older adults and patients with subcortical vascular cognitive impairment no dementia use different coping strategies and distinct functional lateralization patterns of fronto-parietal network to support memory and executive function. This may inform cognitive training intervention to help prevent Alzheimer’s disease and other neurodegenerative diseases.

Graphical Abstract