Abacus in the brain: a longitudinal functional MRI study of a skilled abacus user with a right hemispheric lesion

Right Fusiform Gray Matter Volume in Children with Long-Term Abacus Training Positively Correlates with Arithmetic Ability

Abacus-based mental calculation (AMC) training has a positive effect on number-related cognitive abilities. While visuospatial strategy may distinguish AMC from conventional calculation method, the underlying neural mechanism is still elusive. The current study aimed to address this question by examining the plasticity of fusiform induced by AMC training and whether this training affects the association between the volume of fusiform and behavioral performance in numerical cognitive tasks using voxel-based morphometry analysis. The results showed that gray matter volumes of bilateral fusiform were significantly smaller in the AMC group relative to the control group. In addition, the volume of right fusiform was positively correlated with digit memory span and negatively correlated with reaction time of an arithmetic operation task only within the AMC group. These results indicate that bilateral fusiform may be the essential neural substrate for AMC experts to recognize and reconstruct abacus-based representations for numbers. These results may advance our understanding of the neural mechanisms of AMC and shield some lights to potential interactions between brain development and cognitive training in children.

Early Event-Related Potential During Figure and Object Perception of Abacus Mental Calculation Training Children: A Randomized Controlled Trial

The aim of this study was to discuss the effect of abacus mental calculation (AMC) on the early processing of children’s perception on numbers and objects. We designed a randomized controlled trial, and a total of 28 subjects were randomly distributed into two groups of equal numbers, namely, one group that received AMC training (training group) and the other group that did not receive training (non-training group). The subjects were asked to determine the figures and objects shown on the computer screen and were recorded on the computer. The event-related potential (ERP) component (N1, N170, P1, and P2) of different brain areas between the two subject groups was compared. Compared with the non-training group, the training group’s P1 in the occipital region showed a larger amplitude and a longer potential period. For N1, the training group showed a longer potential period. Additionally, for N170, the training group showed a smaller amplitude. Finally, the observation of P2 showed a smaller amplitude in the training group and a longer potential period in the condition of object stimulus. Overall, the activated degree of the occipital region of children who received AMC training was enhanced, while the activated degree of the central region of the forehead and temporal occipital region was slightly down. Meanwhile, the potential periods of all components were extended. Therefore, long-term AMC training can change children’s cortical function activities.

An ERP study on the influence of mental abacus calculation on subthreshold arithmetic priming in children

OBJECTIVE

The objective of this study was to investigate the influence of mental abacus calculation training (MACT) on subliminal cognitive processes.

METHODS

Twenty children with intensive MACT (MACT group) and 20 children without MACT (non-MACT group) were selected. The two groups of children were matched in age, sex, handedness and academic grade. The participants were tested with subthreshold arithmetic priming task while their neural activities were recorded with a 32-channel electroencephalogram system.

RESULTS

We found that MACT changed the subliminal cognitive mechanism of computational processing, speeding up the computation. MACT affected the computational processing mode. Specifically, in the identification stage, both groups of children adopted the visual space processing mode, while in the computing stage, the MACT group adopted a visual space processing mode, but the non-MACT group adopted a semantic processing mode. Moreover, MACT improved children's executive functions.

CONCLUSION

These results yielded insights into the effect of early abacus training on children's cognitive processing, providing a theoretical basis for the development and promotion of abacus training.

Neural correlates of improved inductive reasoning ability in abacus-trained children: A resting state fMRI study

Abacus-based mental calculation (AMC) training may improve mathematics-related abilities and transfer to other cognitive domains. Thus, it was hypothesized that inductive reasoning abilities can be improved by AMC training given the overlapping cognitive processes and neural correlates between AMC and inductive reasoning. The aim of the current study was to examine the underlying neurobiological mechanisms of this possible adaption by resting-state functional magnetic resonance imaging (rs-fMRI). Sixty-three children were randomly assigned to either the AMC-trained or the nontrained group. The AMC-trained group was required to perform abacus training for 2 hours per week for 5 years whereas the nontrained group was not required to perform any abacus training. Each participant's rs-fMRI data were collected after abacus training, and regional homogeneity (ReHo) analysis was performed to determine the neural activity differences between groups. The participants' posttraining mathematical ability, intelligence quotients, and inductive reasoning ability were recorded and evaluated. The results revealed that AMC-trained children exhibited a significantly higher mathematical ability and inductive reasoning performance and higher ReHo in the rostrolateral prefrontal cortex (RLPFC) compared to the nontrained group. In particular, the increased ReHo in the RLPFC was found to be positively correlated with improved inductive reasoning performance. Our findings suggest that rs-fMRI may reflect the modulation of training in task-related networks.

Expert Programmers Have Fine-Tuned Cortical Representations of Source Code

Expertise enables humans to achieve outstanding performance on domain-specific tasks, and programming is no exception. Many studies have shown that expert programmers exhibit remarkable differences from novices in behavioral performance, knowledge structure, and selective attention. However, the underlying differences in the brain of programmers are still unclear. We here address this issue by associating the cortical representation of source code with individual programming expertise using a data-driven decoding approach. This approach enabled us to identify seven brain regions, widely distributed in the frontal, parietal, and temporal cortices, that have a tight relationship with programming expertise. In these brain regions, functional categories of source code could be decoded from brain activity and the decoding accuracies were significantly correlated with individual behavioral performances on a source-code categorization task. Our results suggest that programming expertise is built on fine-tuned cortical representations specialized for the domain of programming.

A Review of the Effects of Abacus Training on Cognitive Functions and Neural Systems in Humans

Abacus, which represents numbers via a visuospatial format, is a traditional device to facilitate arithmetic operations. Skilled abacus users, who have acquired the ability of abacus-based mental calculation (AMC), can perform fast and accurate calculations by manipulating an imaginary abacus in mind. Due to this extraordinary calculation ability in AMC users, there is an expanding literature investigating the effects of AMC training on cognition and brain systems. This review study aims to provide an updated overview of important findings in this fast-growing research field. Here, findings from previous behavioral and neuroimaging studies about AMC experts as well as children and adults receiving AMC training are reviewed and discussed. Taken together, our review of the existing literature suggests that AMC training has the potential to enhance various cognitive skills including mathematics, working memory and numerical magnitude processing. Besides, the training can result in functional and anatomical neural changes that are largely located within the frontal-parietal and occipital-temporal brain regions. Some of the neural changes can explain the training-induced cognitive enhancements. Still, caution is needed when extend the conclusions to a more general situation. Implications for future research are provided.

Time Series Analysis in Forecasting Mental Addition and Summation Performance

An ideal performance evaluation metric would be predictive, objective, easy to administer, estimate the variance in performance, and provide a confidence interval for the level of uncertainty. Time series forecasting may provide objective metrics for predictive performance in mental arithmetic. Addition and summation (addition combined with subtraction) using the Japanese Soroban computation system was undertaken over 60 days. The median calculation time in seconds for adding 10 sequential six digit numbers [CT_Add) was 63 s (interquartile range (IQR) = 12, range 48-127 s], while that for summation (CT_Sum) was 70 s (IQR = 14, range 53-108 s), and the difference between these times was statistically significant p < 0.0001. Using the mean absolute percentage error (MAPE) to measure forecast accuracy, the autoregressive integrated moving average (ARIMA) model predicted a further reduction in both CT_Add to a mean of 51.51 ± 13.21 s (AIC = 5403.13) with an error of 6.32%, and CT_Sum to a mean of 54.57 ± 15.37 s (AIC = 3852.61) with an error of 8.02% over an additional 100 forecasted trials. When the testing was repeated, the actual mean performance differed by 1.35 and 4.41 s for each of the tasks, respectively, from the ARIMA point forecast value. There was no difference between the ARIMA model and actual performance values (p-value CT_Add = 1.0, CT_Sum=0.054). This is in contrast to both Wright's model and linear regression (p-value < 0.0001). By accounting for both variability in performance over time and task difficulty, forecasting mental arithmetic performance may be possible using an ARIMA model, with an accuracy exceeding that of both Wright's model and univariate linear regression.

Neural Processing Mechanism of Mental Calculation Based on Cerebral Oscillatory Changes: A Comparison Between Abacus Experts and Novices

Background: Abacus experts could mentally calculate fast some mathematical operations using multi-digit numbers. The temporal dynamics of abacus mental calculation are still unknown although some behavioral and neuroimaging studies have suggested a visuospatial and visuomotor neural process during abacus mental calculation. Therefore, this contribution aims to clarify the significant similarities and the differences between experts and novices by investigating calculation-induced neuromagnetic responses based on cerebral oscillatory changes.

Methods: Twelve to 13 healthy abacus experts and 17 non-experts participated in two experimental paradigms using non-invasive neuromagnetic measurements. In experiments 1 and 2, the spatial distribution of oscillatory changes presented mental calculations and temporal frequency profiles during addition while examining multiplication tasks. The MEG data were analyzed using synthetic aperture magnetometry (SAM) with an adaptive beamformer to calculate the group average of the spatial distribution of oscillatory changes and their temporal frequency profiles in source-level analyses.

Results: Using a group average of the spatial distribution of oscillatory changes, we observed some common brain activities in both right-handed abacus experts and non-experts. In non-experts, we detected the right dorsolateral prefrontal cortex (DLPFC) and bilateral Intraparietal sulcus (IPS); whereas in experts, detected the bilateral parieto-occipital sulcus (POS), right inferior frontal gyrus (IFG), and left sensorimotor areas mainly. Based on the findings generated, we could propose calculation processing models for both abacus experts and non- experts conveniently.

Conclusion: The proposed model of calculation processing in abacus experts and novices revealed that the novices could calculate logically depending on numerical processing in the left IPS. In contrast, abacus experts are utilizing spatial processing using a memorized imaginary abacus, which distributed over the bilateral hemispheres in the IFG and sensorimotor areas.

Training on Abacus-Based Mental Calculation Enhances Visuospatial Working Memory in Children

Abacus-based mental calculation (AMC) involves temporary storage and manipulation of an imaginary abacus closely related to the function of visuospatial working memory (VSWM). The present study thus investigated the effects of AMC training on VSWM and its neural correlates. A total of 144 human subjects (67 boys) were assigned to AMC or control groups at their entry to primary school. The AMC group received 2 h AMC training per week for 5 school years, whereas the control group spent the time in activities, such as conventional calculation and reading. Raven's Intelligence Test was administered both before and after training. Two arithmetic tests and a VSWM task were conducted after training. Among these participants, fMRI data were collected from 64 children for the VSWM task. Behavioral results indicated that the AMC group outperformed controls on both arithmetic and VSWM tasks, but not on Raven's Intelligence Test. While the two groups activated similar regions during the VSWM task, the AMC group showed greater activation than the controls in frontal, parietal, and occipital areas. Interestingly, the activation of right middle frontal gyrus mediated the relation between the arithmetic ability and the VSWM performance in the AMC group, suggesting that the frontal region may be the neural substrate underlying the transfer effect from AMC training to VSWM. Although the transfer effects seem quite limited considering the length and intensity of the training, these findings suggest that long-term AMC training not only improves arithmetic ability but also has a potential positive effect on VSWM.SIGNIFICANCE STATEMENT Plasticity of working memory is one of the most rapidly expanding research fields in the developmental and cognitive sciences. Previous studies suggest that abacus-based mental calculation (AMC) relies on a visuospatial imaginary strategy, which is closely related to visuospatial working memory (VSWM). However, the impacts of AMC training on VSWM and the underlying neural basis remain unclear. Here, we found that AMC training enhanced VSWM in children, which was accompanied by altered activation in frontal, parietal, and occipital areas. Moreover, we observed that activation in right middle frontal gyrus played a significant mediation role in the transfer of AMC training to VSWM. These findings provide a new perspective to VSWM training and also advance our understanding of related brain plasticity.

The impact of long-term abacus training on modular properties of functional brain network

Training induces cognitive and neural plasticity, and understanding of the neural mechanisms of training-induced brain plasticity has significant implications for improving children's academic achievement. Previous studies have indicated that training in abacus-based mental calculation (AMC) improves arithmetical capacities and results in brain plasticity within visuospatial brain regions. However, previous studies have reported alterations within distributed brain regions. Thus, it remains unclear whether and how AMC training influences the functional integration and separation between and/or within networks. The current study aimed to address these questions using graph theory, engaging 162 children, 90 of whom were given long-term AMC training. The AMC group exhibited greater local efficiency and intra-module connections within the visual network and less local efficiency and intra-module connections in the cingulo-opercular network (CON). Interestingly, in the AMC group, negative correlations were found between local efficiency and intra-module connections across the two networks. Furthermore, both network characteristics of the CON were negatively correlated with math ability in the AMC group. No such correlations were found in the control group. The current study delineated the enhanced neural mechanisms of visuospatial-related brain regions at an intermediate level and highlighted the intrinsic association between different brain ensembles in neural plasticity, thus furthering the understanding of the effects of AMC training on brain network reconfiguration.

A Longitudinal Functional Magnetic Resonance Imaging Study of Working Memory in Patients Following a Transient Ischemic Attack: A Preliminary Study

In this study, we used functional magnetic resonance imaging (fMRI) to investigate longitudinal changes in brain activation during a verbal working memory (VWM) task performed by patients who had experienced a transient ischemic attack (TIA). Twenty-five first-ever TIA patients without visible lesions in conventional MRI and 25 healthy volunteers were enrolled. VWM task-related fMRI was conducted 1 week and 3 months post-TIA. The brain activity evoked by the task and changes over time were assessed. We found that, compared with controls, patients exhibited an increased activation in the bilateral inferior frontal gyrus (IFG), right dorsolateral prefrontal cortex (DLPFC), insula, inferior parietal lobe (IPL), and cerebellum during the task performed 1 week post-TIA. But only the right IFG still exhibited an increased activation at 3 months post-TIA. A direct comparison of fMRI data between 1 week and 3 months post-TIA showed greater activation in the bilateral middle temporal gyrus, right DLPFC, IPL, cerebellum, and left IFG in patients at 1 week post-TIA. We conclude that brain activity patterns induced by a VWM task remain dynamic for a period of time after a TIA, despite the cessation of clinical symptoms. Normalization of the VWM activation pattern may be progressively achieved after transient episodes of ischemia in TIA patients.

An event-related potential investigation of spatial attention orientation in children trained with mental abacus calculation

The objective of this study was to investigate the effects of long-term mental abacus calculation training (MACT) on children’s spatial attention orientation. Fifteen children with intensive MACT (MACT group) and 15 children without MACT (non-MACT group) were selected. The two groups of children were matched in age, sex, handedness, and academic grade. The participants were tested with a Posner spatial cueing task while their neural activities were recorded with a 32-channel electroencephalogram system. The participants’ behavior scores (reaction time and accuracy) as well as early components of event-related potential (ERP) during the tests were statistically analyzed. The behavioral scores showed no significant difference between the two groups of children, although the MACT group tended to have a shorter reaction time. The early ERP components showed that under valid cueing condition, the MACT group had significantly higher P1 amplitude [F(1, 28)=5.06, P<0.05, effective size=0.72] and lower N1 amplitude [F(1, 28)=6.05, P<0.05, effective size=0.82] in the occipital region compared with the non-MACT group. In the centrofrontal brain region, the MACT group had lower N1 amplitude [F(1, 28)=4.89, P<0.05, effect size=0.70] and longer N1 latency [F(1, 28)=6.26, P<0.05, effect size=0.80] than the non-MACT group. In particular, the MACT group also showed a higher centrofrontal P2 amplitude in the right hemisphere [F(1, 28)=4.82, P<0.05, effect size 0.81] compared with the left hemisphere and the middle location. MACT enhances the children’s spatial attention orientation, which can be detected in the early components of ERP.

Effect of abacus training on executive function development and underlying neural correlates in Chinese children

Executive function (EF) refers to a set of cognitive abilities involved in self-regulated behavior. Given the critical role of EF in cognition, strategies for improving EF have attracted intensive attention in recent years. Previous studies have explored the effects of abacus-based mental calculation (AMC) training on several cognitive abilities. However, it remains unclear whether AMC training affects EF and its neural correlates. In this study, participants were randomly assigned to AMC or control groups upon starting primary school. The AMC group received 2 h AMC training every week, while the control group did not have any abacus experience. Neural activity during an EF task was examined using functional MRI for both groups in their 4th and 6th grades. Our results showed that the AMC group performed better and faster than the control group in both grades. They also had lower activation in the frontoparietal reigons than the control group in the 6th grade. From the 4th to the 6th grade, the AMC group showed activation decreases in the frontoparietal regions, while the control group exhibited an opposite pattern. Furthermore, voxel-wise regression analyses revealed that better performance was associated with lower task-relevant brain activity in the AMC group but associated with greater task-relevant brain activity in the control group. These results suggest that long-term AMC training, with calculation ability as its original target, may improve EF and enhance neural efficiency of the frontoparietal regions during development. Hum Brain Mapp 38:5234-5249, 2017. © 2017 Wiley Periodicals, Inc.

The Effects of Long-term Abacus Training on Topological Properties of Brain Functional Networks

Previous studies in the field of abacus-based mental calculation (AMC) training have shown that this training has the potential to enhance a wide variety of cognitive abilities. It can also generate specific changes in brain structure and function. However, there is lack of studies investigating the impact of AMC training on the characteristics of brain networks. In this study, utilizing graph-based network analysis, we compared topological properties of brain functional networks between an AMC group and a matched control group. Relative to the control group, the AMC group exhibited higher nodal degrees in bilateral calcarine sulcus and increased local efficiency in bilateral superior occipital gyrus and right cuneus. The AMC group also showed higher nodal local efficiency in right fusiform gyrus, which was associated with better math ability. However, no relationship was significant in the control group. These findings provide evidence that long-term AMC training may improve information processing efficiency in visual-spatial related regions, which extend our understanding of training plasticity at the brain network level.

Configured-groups hypothesis: fast comparison of exact large quantities without counting

Our innate number sense cannot distinguish between two large exact numbers of objects (e.g., 45 dots vs 46). Configured groups (e.g., 10 blocks, 20 frames) are traditionally used in schools to represent large numbers. Previous studies suggest that these external representations make it easier to use symbolic strategies such as counting ten by ten, enabling humans to differentiate exactly two large numbers. The main hypothesis of this work is that configured groups also allow for a differentiation of large exact numbers, even when symbolic strategies become ineffective. In experiment 1, the children from grade 3 were asked to compare two large collections of objects for 5 s. When the objects were organized in configured groups, the success rate was over .90. Without this configured grouping, the children were unable to make a successful comparison. Experiments 2 and 3 controlled for a strategy based on non-numerical parameters (areas delimited by dots or the sum areas of dots, etc.) or use symbolic strategies. These results suggest that configured grouping enables humans to distinguish between two large exact numbers of objects, even when innate number sense and symbolic strategies are ineffective. These results are consistent with what we call "the configured group hypothesis": configured groups play a fundamental role in the acquisition of exact numerical abilities.

The impact of abacus training on working memory and underlying neural correlates in young adults

Abacus-based mental calculation (AMC) activates the frontoparietal areas largely overlapping with the working memory (WM) network. Given the critical role of WM in cognition, how to improve WM capability has attracted intensive attention in past years. However, it is still unclear whether WM could be enhanced by AMC training. The current research thus explored the impact of AMC training on verbal and visuospatial WM, as well as the underlying neural basis. Participants were randomly assigned to an abacus group and a control group. Their verbal WM was evaluated by digit/letter memory span (DMS/LMS) tests, and visuospatial WM was assessed by a visuospatial n-back task. Neural activity during the n-back task was examined using functional MRI. Our results showed reliable improvements of both verbal and visuospatial WM in the abacus group after 20-day AMC training but not in the control. In addition, the n-back task-induced activations in the right frontoparietal circuitry and left occipitotemporal junction (OTJ) declined as a result of training. Notably, the decreases in activity were positively correlated with performance gains across trained participants. These results suggest AMC training not only improves calculating skills but also have the potential to promote individuals' WM capabilities, which is associated with the functional plasticity of the common neural substrates.

Memory Updating and Mental Arithmetic

Is domain-general memory updating ability predictive of calculation skills or are such skills better predicted by the capacity for updating specifically numerical information? Here, we used multidigit mental multiplication (MMM) as a measure for calculating skill as this operation requires the accurate maintenance and updating of information in addition to skills needed for arithmetic more generally. In Experiment 1, we found that only individual differences with regard to a task updating numerical information following addition (MUcalc) could predict the performance of MMM, perhaps owing to common elements between the task and MMM. In Experiment 2, new updating tasks were designed to clarify this: a spatial updating task with no numbers, a numerical task with no calculation, and a word task. The results showed that both MUcalc and the spatial task were able to predict the performance of MMM but only with the more difficult problems, while other updating tasks did not predict performance. It is concluded that relevant processes involved in updating the contents of working memory support mental arithmetic in adults.

Neural Plasticity following Abacus Training in Humans: A Review and Future Directions

The human brain has an enormous capacity to adapt to a broad variety of environmental demands. Previous studies in the field of abacus training have shown that this training can induce specific changes in the brain. However, the neural mechanism underlying these changes remains elusive. Here, we reviewed the behavioral and imaging findings of comparisons between abacus experts and average control subjects and focused on changes in activation patterns and changes in brain structure. Finally, we noted the limitations and the future directions of this field. We concluded that although current studies have provided us with information about the mechanisms of abacus training, more research on abacus training is needed to understand its neural impact.

Long-Term Abacus Training Induces Automatic Processing of Abacus Numbers in Children

Abacus-based mental calculation (AMC) is a unique strategy for arithmetic that is based on the mental abacus. AMC experts can solve calculation problems with extraordinarily fast speed and high accuracy. Previous studies have demonstrated that abacus experts showed superior performance and special neural correlates during numerical tasks. However, most of those studies focused on the perception and cognition of Arabic numbers. It remains unclear how the abacus numbers were perceived. By applying a similar enumeration Stroop task, in which participants are presented with a visual display containing two abacus numbers and asked to compare the numerosity of beads that consisted of the abacus number, in the present study we investigated the automatic processing of the numerical value of abacus numbers in abacus-trained children. The results demonstrated a significant congruity effect in the numerosity comparison task for abacus-trained children, in both reaction time and error rate analysis. These results suggested that the numerical value of abacus numbers was perceived automatically by the abacus-trained children after long-term training.

Abacus training modulates the neural correlates of exact and approximate calculations in Chinese children: an fMRI study

Exact (EX) and approximate (AP) calculations rely on distinct neural circuits. However, the training effect on the neural correlates of EX and AP calculations is largely unknown, especially for the AP calculation. Abacus-based mental calculation (AMC) is a particular arithmetic skill that can be acquired by long-term abacus training. The present study investigated whether and how the abacus training modulates the neural correlates of EX and AP calculations by functional magnetic resonance imaging (fMRI). Neural activations were measured in 20 abacus-trained and 19 nontrained Chinese children during AP and EX calculation tasks. Our results demonstrated that: (1) in nontrained children, similar neural regions were activated in both tasks, while the size of activated regions was larger in AP than those in the EX; (2) in abacus-trained children, no significant difference was found between these two tasks; (3) more visuospatial areas were activated in abacus-trained children under the EX task compared to the nontrained. These results suggested that more visuospatial strategies were used by the nontrained children in the AP task compared to the EX; abacus-trained children adopted a similar strategy in both tasks; after long-term abacus training, children were more inclined to apply a visuospatial strategy during processing EX calculations.

The neural pathway underlying a numerical working memory task in abacus-trained children and associated functional connectivity in the resting brain

Training can induce significant changes in brain functioning and behavioral performance. One consequence of training is changing the pattern of brain activation. Abacus training is of interest because abacus experts gain the ability to handle digits with unusual speed and accuracy. However, the neural correlates of numerical memory in abacus-trained children remain unknown. In the current study, we aimed to detect a training effect of abacus-based mental calculations on numerical working memory in children. We measured brain functional magnetic resonance imaging (fMRI) activation patterns in 17 abacus-trained children and 17 control children as they performed two numerical working memory tasks (digits and beads). Functional MRI results revealed higher activation in abacus-trained children than in the controls in the right posterior superior parietal lobule/superior occipital gyrus (PSPL/SOG) and the right supplementary motor area (SMA) in both tasks. When these regions were used as seeds in a functional connectivity analysis of the resting brain, the abacus-trained children showed significantly enhanced integration between the right SMA and the right inferior frontal gyrus (IFG). The IFG is considered to be the key region for the control of attention. These findings demonstrate that extensive engagement of the fronto-parietal network occurs during numerical memory tasks in the abacus-trained group. Furthermore, abacus training may increase the functional integration of visuospatial-attention circuitry, which and thus enhances high-level cognitive process.

Structural changes in left fusiform areas and associated fiber connections in children with abacus training: evidence from morphometry and tractography

Evidence supports the notion that the fusiform gyrus (FG), as an integral part of the ventral occipitotemporal junction, is involved widely in cognitive processes as perceiving faces, objects, places or words, and this region also might represent the visual form of an abacus in the abacus-based mental calculation process. The current study uses a combined voxel-based morphometry (VBM) and diffusion tensor imaging (DTI) analysis to test whether long-term abacus training could induce structural changes in the left FG and in the white matter (WM) tracts distribution connecting with this region in school children. We found that, abacus-trained children exhibited significant smaller gray matter (GM) volume than controls in the left FG. And the connectivity mapping identified left forceps major as a key pathway connecting left FG with other brain areas in the trained group, but not in the controls. Furthermore, mean fractional anisotropy (FA) values within left forceps major were significantly increased in the trained group. Interestingly, a significant negative correlation was found in the trained group between the GM volume in left FG and the mean FA value in left forceps major, suggesting an inverse effect of the reported GM and WM structural changes. In the control group, a positive correlation between left FG GM volume and tract FA was found as well. This analysis visualized the group level differences in GM volume, FA and fiber tract between the abacus-trained children and the controls, and provided the first evidence that GM volume change in the left FG is intimately linked with the micro-structural properties of the left forceps major tracts. The present results demonstrate the structural changes in the left FG from the intracortical GM to the subcortical WM regions and provide insights into the neural mechanism of structural plasticity induced by abacus training.