The Neural Correlates of Numerical Symbol Processing During Symbol-and-Numerosity Paired Learning

Numerical symbol processing develops dynamically from initial learning to proficiency, yet the neural mechanisms underlying this progression remain poorly understood. This study employed an artificial symbol learning paradigm to capture neural responses at different proficiency levels of numerical processing and further explored how these responses relate to task-specific behavioral performance and overall math achievement. Forty-eight adults participated in the artificial symbol learning paradigm, during which event-related potential (ERP) data were recorded. Subsequently, they completed a behavioral math achievement test. A trial-based ERP-behavior correlation approach was used to enhance statistical power. The results showed significant correlations between the N1 and P2 components at occipitoparietal electrodes and reaction time in the numerical comparison task. Additionally, significant correlations were found between the N1 and P2 components and math achievement scores across all sessions. More importantly, the association between the occipital P2 component and reaction time in the comparison task increased across sessions, while the association between the parietal P2 component and math achievement scores decreased. These patterns were not observed in ERP amplitudes. The findings suggest that the P2 component, rather than the N1, serves as a key neural marker for the development of numerical symbol processing. They also highlight the critical role of brain-behavior correlations in elucidating this developmental process.