A cortical semantic map integrates fractions and integers in the human brain
- 1Université Paris Saclay, INSERM, CEA, Cognitive Neuroimaging Unit, NeuroSpin Center, Gif-sur-Yvette, France.
- 2Collège de France, PSL University, Paris, France.
Abstract
How does the human brain represent the meaning of abstract symbols? Some theories postulate the existence of semantic spaces where concepts occupy positions that reflect their conceptual relationships. In the number domain, psychological evidence suggests that integers are represented along a mental number line which, with education, integrates higher-level number concepts such as fractions. To test this hypothesis, we recorded whole-brain 7T fMRI responses to integer and fraction symbols during an active magnitude comparison task designed to engage magnitude processing. Consistent with predictions, we found both behavioral and neural numerical distance effects. Activation vectors in intraparietal, inferior temporal, prefrontal, hippocampal, and parahippocampal cortices formed a two-dimensional semantic space organized by numerical magnitude and domain (fractions versus integers). Gaussian fits revealed a topographic map of numerical preferences in the anterior inferior parietal cortex, common to both domains. Our results suggest that, when educated adults engage in an explicit magnitude comparison task, their brain can construct an ordered representation that integrates fractions and integers, with a topographic organization in the anterior IPS/IPL.
How does the brain represent symbolic integers and fractions? This study shows that educated adults process both integers and fractions within a shared, topographic map in the parietal cortex, indicating that the brain integrates integers and higher-level concepts such as fractions to support the understanding and comparison of numerical magnitudes.
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BibTeX
@article{valerio2026cortical,
title = {{A cortical semantic map integrates fractions and integers in the human brain}},
author = {Daniela Valério and Samuel Debray and Alireza Karami and Maxime Cauté and Nicolás Gravel and Stanislas Dehaene},
journal = {PLOS Biology},
year = {2026},
month = oct,
doi = {10.1371/journal.pbio.3003820},
url = {https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.3003820},
note = {CC BY},
}
RIS
TY - JOUR
TI - A cortical semantic map integrates fractions and integers in the human brain
AU - Daniela Valério
AU - Samuel Debray
AU - Alireza Karami
AU - Maxime Cauté
AU - Nicolás Gravel
AU - Stanislas Dehaene
PY - 2026
DA - 2026/10/22
JO - PLOS Biology
DO - 10.1371/journal.pbio.3003820
UR - https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.3003820
AB - How does the human brain represent the meaning of abstract symbols? Some theories postulate the existence of semantic spaces where concepts occupy positions that reflect their conceptual relationships. In the number domain, psychological evidence suggests that integers are represented along a mental number line which, with education, integrates higher-level number concepts such as fractions. To test this hypothesis, we recorded whole-brain 7T fMRI responses to integer and fraction symbols during an active magnitude comparison task designed to engage magnitude processing. Consistent with predictions, we found both behavioral and neural numerical distance effects. Activation vectors in intraparietal, inferior temporal, prefrontal, hippocampal, and parahippocampal cortices formed a two-dimensional semantic space organized by numerical magnitude and domain (fractions versus integers). Gaussian fits revealed a topographic map of numerical preferences in the anterior inferior parietal cortex, common to both domains. Our results suggest that, when educated adults engage in an explicit magnitude comparison task, their brain can construct an ordered representation that integrates fractions and integers, with a topographic organization in the anterior IPS/IPL. How does the brain represent symbolic integers and fractions? This study shows that educated adults process both integers and fractions within a shared, topographic map in the parietal cortex, indicating that the brain integrates integers and higher-level concepts such as fractions to support the understanding and comparison of numerical magnitudes.
SN - 1545-7885
SN - 1544-9173
ER -