Psychonomic Bulletin & Review

, Volume 25, Issue 2, pp 688–695 | Cite as

The SNARC effect is not a unitary phenomenon

  • Sara Basso Moro
  • Roberto Dell’Acqua
  • Simone Cutini
Brief Report


Models of the spatial–numerical association of response codes (SNARC) effect—faster responses to small numbers using left effectors, and the converse for large numbers—diverge substantially in localizing the root cause of this effect along the numbers’ processing chain. One class of models ascribes the cause of the SNARC effect to the inherently spatial nature of the semantic representation of numerical magnitude. A different class of models ascribes the effect’s cause to the processing dynamics taking place during response selection. To disentangle these opposing views, we devised a paradigm combining magnitude comparison and stimulus–response switching in order to monitor modulations of the SNARC effect while concurrently tapping both semantic and response-related processing stages. We observed that the SNARC effect varied nonlinearly as a function of both manipulated factors, a result that can hardly be reconciled with a unitary cause of the SNARC effect.


SNARC effect Stimulus–response mapping Numerical distance effect Magnitude comparison Spatial–numerical associations 

Supplementary material

13423_2017_1408_MOESM1_ESM.docx (115 kb)
ESM 1 (DOCX 115 kb)


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Copyright information

© Psychonomic Society, Inc. 2017

Authors and Affiliations

  • Sara Basso Moro
    • 1
  • Roberto Dell’Acqua
    • 2
    • 3
  • Simone Cutini
    • 2
    • 3
  1. 1.Department of NeuroscienceUniversity of PaduaPaduaItaly
  2. 2.Department of Developmental PsychologyUniversity of PaduaPaduaItaly
  3. 3.Padova Neuroscience CenterUniversity of PaduaPaduaItaly

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