Animal Cognition

, Volume 20, Issue 5, pp 999–1002 | Cite as

Do ‘literate’ pigeons (Columba livia) show mirror-word generalization?

Short Communication


Many children pass through a mirror stage in reading, where they write individual letters or digits in mirror and find it difficult to correctly utilize letters that are mirror images of one another (e.g., b and d). This phenomenon is thought to reflect the fact that the brain does not naturally discriminate left from right. Indeed, it has been argued that reading acquisition involves the inhibition of this default process. In the current study, we tested the ability of literate pigeons, which had learned to discriminate between 30 and 62 words from 7832 nonwords, to discriminate between words and their mirror counterparts. Subjects were sensitive to the left–right orientation of the individual letters, but not the order of letters within a word. This finding may reflect the fact that, in the absence of human-unique top-down processes, the inhibition of mirror generalization may be limited.


Mirror generalization Reading Pigeon Vision Comparative cognition 



This work was supported by University of Otago Department of Psychology research funds to M.C.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

This research was approved by the University of Otago Animal Ethics Committee.


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Copyright information

© Springer-Verlag GmbH Germany 2017

Authors and Affiliations

  1. 1.Department of PsychologyUniversity of OtagoDunedinNew Zealand
  2. 2.School of PsychologyUniversity of AucklandAucklandNew Zealand
  3. 3.Department of Psychology, Institute of Cognitive Neuroscience, BiopsychologyRuhr-University BochumBochumGermany

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