Reduced Dependence on Sensorimotor Processing in the Brain is Associated with Higher Math Skills in Adults

Abstract Number processing is crucial for math competence, yet the neural underpinnings remain unclear. In this study, we used functional magnetic resonance imaging (fMRI) to 1) identify key brain regions involved in symbolic and embodied number processing, and 2) examine their relations with math abilities in children and adults. We collected fMRI data from 104 adults ( M age = 23.25 years) and 88 4 th graders ( M age = 9.75) as they performed number comparison and phonological tasks with numeral (symbolic) and hand (embodied) numerical stimuli. Participants’ math abilities were assessed using the math subtests of the Woodcock-Johnson Tests of Achievement. Univariate analyses revealed number processing regions in occipital, parietal and temporal cortices including inferior parietal, sensorimotor, supramarginal and insular areas. In adults, less involvement of sensorimotor processing regions during number compared to phonological processing is associated with enhanced math skills. These findings not only elucidate the neural mechanisms underlying number processing and math abilities but also raise questions about the emphasis on embodied number presentation in math learning experiences. Significance Statement Children and adults show substantial individual differences in math competence, and understanding the underlying neural mechanisms is crucial. By employing functional magnetic resonance imaging (fMRI), we identified key brain regions involved in symbolic and embodied number processing and explored their relations with math skills. Our findings reveal that reduced sensorimotor involvement during number processing correlates with enhanced math performance in adults. This study not only elucidates the neural mechanisms underlying number processing, offering critical insights into the cognitive architecture that supports math abilities, but also raises questions about the emphasis on embodied number representations in math learning experiences.