Even for experienced readers, mirror-image letters like b/d or p/q can be confusing. Why is it difficult for some to differentiate these letters?
When learning to read, our brain must be able to inhibit the mirror-generalization process, a mechanism that facilitates the recognition of identical objects regardless of their orientation, but also prevents the brain from differentiating letters that are different but symmetrical. In recent years, many studies on the process of learning to read have been based on the neuronal recycling hypothesis: the reuse of old brain mechanisms in a new adaptive role - a kind of "biological trick." Specifically, neurons that are originally dedicated to the rapid identification of objects in the environment, through the mirror-generalization process, are "re-purposed" during childhood to specialize in the visual recognition of letters and words.
In a study conducted by the researchers of the Laboratoire de Psychologie du Développement et de l'Education de l'Enfant (CNRS / Université Paris Descartes / Université de Caen Basse-Normandie), researchers showed 80 young adults pairs of images, first two letters and then two animals, asking them to determine whether they were identical. The readers consistently spent more time determining that two animal images, when preceded by mirror-image letters, were indeed identical.
In the experimental sequence, a pair of identical animals (e.g. horses) is preceded on the screen by a pair of mirror-image letters (b and d), or, in the control condition, a pair of non-mirror-image letters (f and t). The participant must decide in each case whether the two items (letters or animals) are identical or not. ©Laboratoire de Psychologie du Développement et de l'Éducation de l'Enfant - LaPsyDÉ (CNRS/Université Paris Descartes, Sorbonne-Paris-Cité /Université de Caen Basse-Normandie)
This increase in response time is called "negative priming": the readers had to inhibit the mirror-generalization process in order to distinguish letters like b/d or p/q. They then needed a little more time to reactivate this strategy when it became useful again to quickly identify animals.
The results show that even adults need to inhibit the mirror-generalization process to avoid reading errors.
Children must therefore learn to inhibit this strategy when learning to read. A failure of cognitive inhibition during the recycling of visual neurons in the brain could thus be a factor in dyslexia - a direction worth exploring in light of these findings, the authors say.
Citation: Grégoire Borst, Emmanuel Ahr, Margot Roell, and Olivier Houdé, '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', Psychonomic Bulletin&Review, 23 May 2014. DOI: 10.3758/s13423-014-0663-9. Source: CNRS (Délégation Paris Michel-Ange)
- PHYSICAL SCIENCES
- EARTH SCIENCES
- LIFE SCIENCES
- SOCIAL SCIENCES
Subscribe to the newsletter
Stay in touch with the scientific world!
Know Science And Want To Write?
- Planck on BICEP2 "It turns out that the part of the dust had been significantly underestimated." UPDATED
- Prevent Alzheimer's Disease By Drinking Beer?
- BICEP2 Found Interstellar Dust, Not Primordial Gravitational Waves
- Acceptance Of Evolution Is Far Higher Than Acceptance Of Other Biology
- The ATLAS Top Production Asymmetry And One Thing I Do Not Like Of It
- Hardwired For Miscommunication? Why Women Think Sex When Men Just Want To Be Friends
- "Well, in principle yes, you can decide that a priori, and then live with whatever result it gives..."
- "Not true. A study by Dan Kahan of Yale Law School found that vaccine denialists are slightly more..."
- "I understand your point, and I have hundreds of friends and acquaintances in evolutionary biology..."
- "This article is an oversimplification and reveals the author's preferences for what is important..."
- "Some pictures of seeds and flowers from a Rothamstead article...."
- New instrument can detect atmospheric mercury
- The enigma of crustal zircons in upper-mantle rocks
- Why does shoveling snow increase risk of heart attacks?
- Stress balls, watching movies and talking ease pain and anxiety during surgery
- Black beauty meteorite may represent 'bulk background' of Mars' battered crust