What's Behind a "+" Sign? Perceiving an Arithmetic Operator Recruits Brain Circuits for Spatial Orienting.
Do mathematical symbols evoke spatial representations? Although behavioral studies have long demonstrated interactions between space and the processing of Arabic digits, how to interpret these results remains controversial. Here, we tested whether activity in regions supporting spatial processing contributes to the processing of symbols conveying fundamental arithmetic concepts-such as operation signs-even in the absence of associated digits. Using functional magnetic resonance imaging, we show that merely perceiving a "+" sign triggers activity in brain regions that support the orienting of spatial attention in adults. Activity in these regions was greater for "+" than for "×" signs, indicating that it is modulated by whether an operator reflects an operation that evokes numerical manipulation (rather than rote memorization). Finally, the degree to which subjects activated a spatial region in response to a "+" sign was correlated with the degree to which subjects benefited from being briefly presented with that sign before having to calculate a single-digit addition problem, an effect termed operator-priming. Therefore, not only are some arithmetic operators linked to spatial intuitions, but such intuitions might also have an important role during arithmetic calculation. More generally, our findings support the view that mathematical symbols inherently evoke spatial representations.
Institut des Sciences Cognitives Marc Jeannerod, UMR 5304, Centre National de la Recherche Scientifique (CNRS), Université Lyon 1, Bron, France.|Faculté de Psychologie et des Sciences de l'Education, Université de Genève, 1205 Genève, Switzerland.
Romain
R
Mathieu
Institut des Sciences Cognitives Marc Jeannerod, UMR 5304, Centre National de la Recherche Scientifique (CNRS), Université Lyon 1, Bron, France.
Justine
J
Epinat-Duclos
Laboratoire CREATIS, Université Lyon 1, CNRS/INSERM, INSA-Lyon & HCL, Lyon, France.
Monica
M
Sigovan
Institut des Sciences Cognitives Marc Jeannerod, UMR 5304, Centre National de la Recherche Scientifique (CNRS), Université Lyon 1, Bron, France.
Audrey
A
Breton
Institut des Sciences Cognitives Marc Jeannerod, UMR 5304, Centre National de la Recherche Scientifique (CNRS), Université Lyon 1, Bron, France.
Anne
A
Cheylus
Clermont II & CNRS, UFR de Psychologie, LAPSCO, Université Blaise Pascal, 63037 Clermont-Ferrand, France.
Michel
M
Fayol
Institut de Psychologie, Université de Lausanne, 1015 Lausanne, Switzerland.
Catherine
C
Thevenot
Institut des Sciences Cognitives Marc Jeannerod, UMR 5304, Centre National de la Recherche Scientifique (CNRS), Université Lyon 1, Bron, France.
Jérôme
J
Prado
D000293:Adolescent; D000328:Adult; D001288:Attention / Q000502:physiology; D001921:Brain / Q000000981:diagnostic imaging / Q000502:physiology*; D001931:Brain Mapping; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008433:Mathematics; D009434:Neural Pathways / Q000000981:diagnostic imaging / Q000502:physiology; D010100:Oxygen / Q000097:blood; D010364:Pattern Recognition, Visual / Q000502:physiology*; D013028:Space Perception / Q000502:physiology*; D055815:Young Adult
D010100:Oxygen