The brain against words in the mirror

March 31, 2011
The visual system can rotate the words reflected in the mirror. Credit: SINC

Most people can read texts reflected in a mirror slowly and with some effort, but a team of scientists from the Basque Centre on Cognition, Brain and Language (BCBL) has shown for the first time that we can mentally turn these images around and understand them automatically and unconsciously, at least for a few instants.

"At a very early processing stage, between 150 and 250 milliseconds, the completely rotates the words reflected in the and recognises them", Jon Andoni Duñabeitia, lead author of the study, tells SINC, "although the then immediately detects that this is not the correct order and 'remembers' that it should not process them in this way".

In order to carry out this study, which has been published in the journal NeuroImage, the researchers used electrodes to monitor the brain activity of 27 participants while carrying out two experiments in front of a computer screen.

In the first, the participants were shown words with some of the letters and other information rotated for 50 milliseconds (an imperceptible flash, which is processed by the brain); while in the second case the entire word in the mirror was rotated (for example HTUOM instead of MOUTH).

The results of the encephalogram showed in both cases that, at between 150 and 250 milliseconds, the brain's response upon seeing the words as reflected in the mirror was the same as when they are read normally.

Better understanding of dyslexia

"These results open a new avenue for studying the effects of involuntary rotation of letters and words in individuals with reading difficulties (dyslexia) and writing problems (dysgrafia)", Duñabeitia explains.

The researcher gives reassurance to parents who worry when their children reverse their letters when they start to write: "This is the direct result of the mirror rotation property of the visual system". In fact, it is common for children to start to write this way until they learn the "established" forms at school.

"Now we know that rotating letters is not a problem that is exclusive to some dyslexics, since everybody often does this in a natural and unconscious way, but what we need to understand is why people who can read normally can inhibit this, while others with difficulties in reading and writing cannot, confusing 'b' for 'd', for example", explains Duñabeitia.

The scientific community has yet to discover how reading, a skill that is learnt relatively late in human development, can inhibit mental rotation in a mirror, a visual capacity that is common to many animals.

"A tiger is a tiger on the right side and the left side, but a word read in the mirror loses its meaning – although now we know that it is not as incomprehensible for our visual system as we thought, because it is capable of processing it as if it were correct", the researcher concludes.

More information: Jon Andoni Duñabeitia, Nicola Molinaro y Manuel Carreiras. "Through the looking-glass: Mirror reading". NeuroImage 54 (4): 3004, February 2011.

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not rated yet Mar 31, 2011
Recalling only from my memory about reading of a famous experiment, because the research here reminds of that work:

Wear glasses. The glasses invert all things seen - turns them upside down - like standing on your head. The brain re-inverts ('corrects') this upside down visual perception after a brief period. Adapts(?) to this artificial sight.
As if the glasses never existed or don't exist.

Removing those glasses, the adaption(?) effects lingers - now all that is seen, appears upside down for a brief period.
After a brief period, the brain re-interprets(?) the visual perception - you no longer 'see', as if everything seen, is upside down.

As if you never wore the glasses that place the world on it's head.

To Jon, Nicola:
How about giving dyslexics 'glasses' - reversing the patient's condition? And ascertain all physical parameters the brain asserts to adapt to the glasses.

Kudos towards your research. :)
not rated yet Mar 31, 2011
The results of the encephalogram showed in both cases that, at between 150 and 250 milliseconds, the brain's response upon seeing the words as reflected in the mirror was the same as when they are read normally.

The results only state that there is a similar response to the image whether it is displayed normally, reversed or rotated, not necessarily that there is 'recognition' of what the words in the image actually says. Possibly the similar response that they have correlated is just that an image (any image) was displayed. ie. The mind saying... "OK.. here's an image to process". To assume that the brain's response was in any way a form of recognition is unscientific unless the subjects were tested and were able to recognize said images only after they were shown for a duration (at between 150 and 250 millisecond) required to invoke a brain response.
not rated yet Mar 31, 2011
in a mirror, your left and right are flipped.. but not up with down... no matter which way you orient yourself

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