Reconfiguration On The Community Structure And Hubs Architecture Of Functional Brain Network After Long-term Abacus Training

Neural plasticity is assumed to underpin the behavioral enhancement during cognitive interventions.And recent application of complex network analysis has paved a new way for the exploration of the training-induced neural plasticity.Notably,the community structure(CS)and hubs architecture of functional brain network have been demonstrated to play an essential role in human cognition.Previous studies of cognitive intervention found the reconfiguration of CS and hubs architecture,and assumed it as an important neural mechanism of human learning.The abacus-based mental calculation(AMC)training could benefit diverse cognitions,accompanied by the influential impact on both structural and functional features of human brain.Recent studies on AMC training also indicated its topological optimization within the visuospatial related brain areas.However,unknown remains whether the CS or hubs architecture could also be reconfigured during the training.Therefore,this article aims to systematically explore this issue with three studies.The first study attempted to investigate whether and how the CS adapts to long-term AMC training.To do so,we recruited 35 children who received 2-h AMC training per week for 5 school years and 31 matched controls.Using the resting-state fMRI data,we constructed the functional brain network for each subject.Our main findings include:(1)the CS was significantly altered between groups;2)the altered CS focused on selective subsets of cortical regions(i.e.,the "core areas"),which were predominantly affiliated to the visual,somatomotor,and default-mode regions(i.e.,the MRC);3)the reorganization of MRC is characterized by more localized cortical processing in the AMC group;4)the whole network displayed enhanced segregation in the AMC group,in which the"core areas" play an important role.In conclusion,this study suggested that the CS could become adaptively reconfigured in response to long-term AMC training,characterized by more localized processing and segregated architecture.Moreover,the adaptive reconfiguration mainly focused on the brain regions related to the visuospatial processing and default network.The second study sought to explore whether and how the hubs architecture adapts to long-term AMC training.In contrast to the first study,we conducted the pre/post design to exclude the potential confounding factors from the pre-training.Our main results include:(1)both groups exhibited typical rich-club phenomenon in the pre-and post-test;(2)the AMC training reconfigure the hubs architecture of functional brain network,and enhanced the probability of several brain regions to be identified as hubs,mainly including the bilateral occipital and posterior cingulate gyrus;(3)the AMC training promoted the functional connectivity of hubs to the non-hubs.In short,this study showed that AMC training could reconfigure the hubs architecture of functional brain network,with brain regions related to the visuospatial processing and default network being more likely to be identified as hubs.And the training could also promote the connectivity between hubs and non-hubs.The third study combined the CS and hubs architecture to explore how the long-term AMC training impacts the provincial hubs and connector hubs,respectively.Our main observations include:(1)the AMC training enhanced the functional connectivity within provincial hubs;(2)the AMC training undermined the functional connectivity between provincial and connector hubs;(3)no significant effect of AMC training was observed towards the functional integration of the whole network.This study suggested that AMC training may be beneficial to the functional segregation,in terms of the weakened connections between provincial and connector hubs,and the strengthened corporation within provincial hubs.In summary,this article explored,for the first time to our knowledge,the neural plasticity of CS and hubs architecture of functional brain network induced by long-term AMC training.We found that AMC training could significantly alter the CS and hubs architecture of brain network,with the "core areas" of such alteration mainly located in the visuospatial related brain areas and default-mode network.And the alteration exhibited a prominent feature to be beneficial to the functional segregation of human brain network.