ArticleProceedings of the National Academy of Sciences of the United States of America2022
An insect brain organizes numbers on a left-to-right mental number line.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 27 papers.
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Who cites it
27 citing papers in PubMed, 71 citations in OpenAlex.
- Exploring emotional expression in invertebrates: mechanisms, functions and phylogeny.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2026Review
- Initial organization and progressive expansion of the math-responsive brain network during the first school years.Proceedings of the National Academy of Sciences of the United States of America · 2026Article
- Numbers Driving Space: Experience With Numerical Sequences Modulates Spatial Behavior in Newborn Chicks (Gallus gallus).Annals of the New York Academy of Sciences · 2026Article
- The Effect of Writing Direction and Task-Specific Experience on Mapping Time and Numbers on Space.Annals of the New York Academy of Sciences · 2026Article
- Measuring SNARC effect: different task setups reveal divergent spatial-numerical associations.Scientific reports · 2026Article
- Spatial representation of magnitude in rhesus macaques: Investigating SNARC effects in quantity and size dimensions.Learning & behavior · 2026Article
- Kicking the mental number line: a kinematic investigation of numerical processing in childhood.Frontiers in psychology · 2026Article
- Numerically induced attentional biases in horizontal, vertical, and two-dimensional shapes.Scientific reports · 2025Article
- Prenatal light exposure affects number sense and the mental number line in young domestic chicks.eLife · 2025Article
- Article
- Does the Brain Care Which Direction We Read? A Cross-Cultural tDCS Study on Functional Lateralization of Number Processing.Brain and behavior · 2025Article
- A left-to-right bias in number-space mapping across ages and cultures.Nature communications · 2025Article
- Symbolic and non-symbolic numbers differently affect center identification in a number-line bisection task.PloS one · 2025Article
- Interpreting insect behavior through the lens of executive functions.Frontiers in behavioral neuroscience · 2025Article
- One and only SNARC? Spatial-Numerical Associations are not fully flexible and depend on both relative and absolute number magnitude.Royal Society open science · 2025Article
- Dichotomous horizontal representation of acute deterioration risk on illnesses.Scientific reports · 2024Article
- Diversity of visual inputs to Kenyon cells of the Drosophila mushroom body.Nature communications · 2024Article
- Article
- Magnitude shifts spatial attention from left to right in rhesus monkeys as in the human mental number line.iScience · 2024Article
- Honey bees rely on associative stimulus strength after training on an olfactory transitive inference task.Frontiers in psychology · 2024Article
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5 authors at 3 institutions in 3 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The "mental number line" (MNL) is a form of spatial numeric representation that associates small and large numbers with the left and right spaces, respectively. This spatio-numeric organization can be found in adult humans and has been related to cultural factors such as writing and reading habits. Yet, both human newborns and birds order numbers consistently with an MNL, thus raising the question of whether culture is a main explanation for MNL. Here, we explored the numeric sense of honey bees and show that after being trained to associate numbers with a sucrose reward, they order numbers not previously experienced from left to right according to their magnitude. Importantly, the location of a number on that scale varies with the reference number previously trained and does not depend on low-level cues present on numeric stimuli. We provide a series of neural explanations for this effect based on the extensive knowledge accumulated on the neural underpinnings of visual processing in honey bees and conclude that the MNL is a form of numeric representation that is evolutionarily conserved across nervous systems endowed with a sense of number, irrespective of their neural complexity.
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