Neuronal recycling: this is how our brain allows us to read

The new study has been published in Current Biology
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Letters, syllables, words and sentences—spatially arranged sets of symbols that acquire meaning when we read them. But is there an area and cognitive mechanism in our brain that is specifically devoted to reading? Probably not; written language is too much of a recent invention for the brain to have developed structures specifically dedicated to it.

According to this novel paper published in Current Biology, underlying reading there is evolutionarily ancient function that is more generally used to process many other visual stimuli. To prove it, SISSA researchers subjected volunteers to a series of experiments in which they were shown different symbols and images. Some were very similar to words, others were very much unlike reading material, like nonsensical three-dimensional tripods, or entirely abstract visual gratings; the results showed no difference between the way participants learned to recognise novel stimuli across these three domains.

According to the scholars, these data suggest that we process letters and words similarly to how to process any visual stimulus to navigate the world through our visual experiences: we recognise the basic features of a stimulus – shape, size, structure and, yes, even letters and words – and we capture their statistics: how many times they occur, how often they present themselves together, how well one predicts the presence of the other.

Thanks to this system, based on the statistical frequency of specific symbols (or combinations thereof), we can recognise orthography, understand it and therefore immerse ourselves in the pleasure of reading.