The Effects Of Abacus Training On Frontal-parietal Network And Brain Lateralization

The cognitive training-induced functional and structural plasticity have attracted a lot of attention nowadays.The frontal-parietal network is considered as a core executive control network and plays an important role in multiple cognitive functions.However,how cognitive training influence the neural response pattern within frontal-parietal network and the brain network asymmetry remains unknown.The current study aims to combine multimodal neuroimaging data,including task functional magnetic resonance imaging(fMRI),resting-state fMRI and diffusion tensor imaging(DTI)to investigate whether abacus-based mental calculation(AMC)training could induce neural plasticity of the frontal-parietal network,and how it may influence the topography of brain network in terms of left-right hemispheric asymmetry.In the first study,subjects were assigned to an AMC group or a control group.The AMC group received 20 days of AMC training,while the controls did not.Task-fMRI results showed that the AMC training altered activation pattern of frontal-parietal network in an AMC-related task.Specifically,the frontal-parietal network displayed increased sustained and reduced transient activity after training.In addition,similar activation patterns also adaptively transferred to two visuo-spatial tasks with different cognitive demands.The results suggest that frontal-parietal network could be the common neural substrates underlying AMC and visuo-spatial working memory,and AMC training may improve calculation ability and visuo-spatial working memory through training-induced task activation in this network.In the second study,we further investigated the functional and structural plasticity within the frontal-parietal network identified based on the previous study,using resting-state functional connectivity and structural connectivity,respectively.The results showed that functional connectivity strength within the frontal-parietal network was significantly enhanced after AMC training.Further analysis revealed a manifest increase in the functional coupling between bilateral superior parietal lobules(SPL).In addition,the functional bilateral SPL connectivity strength was found positively correlated with short-term memory after AMC training.Moreover,DTI tractography,revealed that the enhanced functional coupling between bilateral SPL was accompanied by decreased axial diffusivity of white matter fiber tracts between bilateral SPL.Together,these results indicate that short-term AMC training might enhance both functional and structural connectivity within the frontal-parietal network,and such brain plasticity may contribute to short-term memory improvement after training.In the third study,we used complex network approach to investigate the influence of AMC training on the asymmetry of brain network properties in two groups of children with a five-year longitudinal design.We found that the asymmetry index did not differ between groups before training,while after five years of AMC training,the local efficiency of network was significantly right lateralized in the AMC group,whereas left lateralization remained in the control group.Particularly,the AMC training increased the degree of right lateralization of the frontal-parietal network studied above.From a network perspective,these results indicate that AMC training might have an impact on brain network,by tuning the lateralization from left towards right hemisphere.In summary,these longitudinal studies above suggest that AMC training may induce brain plasticity in terms of functional and structural changes as well as hemispheric lateralization,with a manifest impact on the frontal-parietal network underlying multiple cognitive functions.Moreover,for the first time,the complex network theory is applied to investigate brian network asymmetry changes induced by cognitive training.The results of current study help to improve the understanding of training-induced neural plasticity with a focus on the frontal-parietal network,and provide a new perspective to investigate cognitive training-induced changes in terms of the brain network asymmetry.