Skip to main content

The cost of blocking the mirror generalization process in reading: evidence for the role of inhibitory control in discriminating letters with lateral mirror-image counterparts


Mirror generalization is detrimental for identifying letters with lateral mirror-image counterparts (‘b/d’). In the present study, we investigated whether the discrimination of this type of letters in expert readers might be rooted in the ability to inhibit the mirror-generalization process. In our negative priming paradigm, participants judged whether two letters were identical on the prime and two animals (or buildings) were identical on the probe. In Experiment 1, participants required more time when determining that two animals (but not two buildings) were mirror images of each other when preceded by letters with mirror-image counterparts than without mirror-image counterparts (‘a/h’). In Experiment 2, we replicated the results with different letters without mirror-image counterparts and with the type of probe stimuli (animal or building) manipulated as a within-subject factors. Our results suggest that expert readers never completely “unlearn” the mirror-generalization process and still need to inhibit this heuristic to overcome mirror errors.

This is a preview of subscription content, access via your institution.

Fig. 1
Fig. 2


  1. Baylis, G. C., & Driver, J. (2001). Shape-coding in IT cells generalizes over contrast and mirror reversal, but not figure-ground reversal. Nature Neuroscience, 4, 937–942.

    PubMed  Article  Google Scholar 

  2. Bolger, D. J., Perfetti, C. A., & Schneider, W. (2005). Cross-cultural effect on the brain revisited: Universal structures plus writing system variation. Human Brain Mapping, 25, 92–104.

    PubMed  Article  Google Scholar 

  3. Bornstein, M., Gross, C., & Wolf, J. (1978). Perceptual similarity of mirror images in infancy. Cognition, 6, 89–116.

    PubMed  Article  Google Scholar 

  4. Borst, G., Moutier, S., & Houdé, O. (2013). Negative priming in logicomathematical reasoning: The cost of blocking your intuition. In W. De Neys & M. Osman (Eds.), New approaches in reasoning research—Current issues in thinking & reasoning (pp. 54–71). New York: Psychology Press.

    Google Scholar 

  5. Dehaene, S. (2013). Inside the Letterbox: How Literacy Transforms the Human Brain. Cerebrum, (June), 1–16.

  6. Dehaene, S., & Cohen, L. (2007). Cultural recycling of cortical maps. Neuron, 56, 384–398.

    PubMed  Article  Google Scholar 

  7. Dehaene, S., Nakamura, K., Jobert, A., Kuroki, C., Ogawa, S., & Cohen, L. (2010). Why do children make mirror errors in reading? Neural correlates of mirror invariance in the visual word form area. NeuroImage, 49, 1837–1848.

    PubMed  Article  Google Scholar 

  8. Diamond, A., Barnett, W. S., Thomas, J., & Munro, S. (2007). Preschool program improves cognitive control. Science, 318, 1387–1388.

    PubMed Central  PubMed  Article  Google Scholar 

  9. Diamond, A., & Kirkham, N. (2005). Not quite as grown-up as we like to think parallels between cognition in childhood and adulthood. Psychological Science, 16, 291–297.

    PubMed Central  PubMed  Article  Google Scholar 

  10. Dilks, D. D., Julian, J. B., Kubilius, J., Spelke, E. S., & Kanwisher, N. (2011). Mirror-image sensitivity and invariance in object and scene processing pathways. The Journal of Neuroscience, 31, 11305–11312.

    PubMed Central  PubMed  Article  Google Scholar 

  11. Duñabeitia, J. A., Dimitropoulou, M., Estévez, A., & Carreiras, M. (2013). The influence of reading expertise in mirror-letter perception: Evidence from beginning and expert readers. Mind, Brain, and Education, 7, 124–135.

    Article  Google Scholar 

  12. Hasson, U., Harel, M., Levy, I., & Malach, R. (2003). Large-scale mirror-symmetry organization of human occipito-temporal object areas. Neuron, 37, 1027–1041.

    PubMed  Article  Google Scholar 

  13. Kolinsky, R., Verhaeghe, A., Fernandes, T., Mengarda, E. J., Grimm-Cabral, L., & Morais, J. (2011). Enantiomorphy through the looking glass: Literacy effects on mirror-image discrimination. Journal of Experimental Psychology: General, 140, 210–238.

    Article  Google Scholar 

  14. Lachmann, T. (2002). Reading disability as a deficit in functional coordination. In Basic functions of language, reading and reading disability (pp. 165–198). Springer US.

  15. Lachmann, T., & van Leeuwen, C. (2007). Paradoxical enhancement of letter recognition in developmental dyslexia. Developmental Neuropsychology, 31, 61–77.

    PubMed  Article  Google Scholar 

  16. Larsson, A., & Smith, T. A. (2012). fMRI repetition suppression: Neuronal adaptation or stimulus expectation? Cerebral Cortex, 22, 567–576.

    PubMed Central  PubMed  Article  Google Scholar 

  17. Neill, W. T., Valdes, L. A., & Terry, K. M. (1995). Selective attention and inhibitory control of cognition. In F. N. Dempster & C. J. Brainerd (Eds.), Interference and inhibition in cognition (pp. 207–261). New York, NY: Academic Press.

    Chapter  Google Scholar 

  18. Orton, S. T. (1925). “Word-blindness” in school children. Archives of Neurology and Psychiatry, 14, 581.

    Article  Google Scholar 

  19. Pegado, F., Nakamura, K., Cohen, L., & Dehaene, S. (2011). Breaking the symmetry: Mirror discrimination for single letters but not for pictures in the visual word form area. NeuroImage, 55, 742–749.

    PubMed  Article  Google Scholar 

  20. Perea, M., Moret-Tatay, C., & Pandero, V. (2011). Suppression of mirror generalization for reversible letters: Evidence from masked priming. Journal of Memory and Language, 65, 237–246.

    Article  Google Scholar 

  21. Rollenhagen, J. E., & Olson, C. R. (2000). Mirror-image confusion in single neurons of the macaque inferotemporal cortex. Science, 287, 1506–1508.

    PubMed  Article  Google Scholar 

  22. Schott, G. D. (2007). Mirror writing: Neurological reflections on an unusual phenomenon. Journal of Neurology, Neurosurgery and Psychiatry, 78, 5–13.

    PubMed Central  PubMed  Article  Google Scholar 

  23. Tipper, S. P. (1985). The negative priming effect: Inhibitory priming by ignored objects. Quarterly Journal of Experimental Psychology, 37A, 571–590.

    Article  Google Scholar 

Download references

Author information



Corresponding author

Correspondence to Grégoire Borst.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Borst, G., Ahr, E., Roell, M. et al. The cost of blocking the mirror generalization process in reading: evidence for the role of inhibitory control in discriminating letters with lateral mirror-image counterparts. Psychon Bull Rev 22, 228–234 (2015).

Download citation


  • Inhibitory control
  • Reading
  • Mirror generalization
  • Neural recycling