When we learn how to write, our brain does not learn the individual lettering of words – instead it is tuned to remember how the word appears as a whole.
That’s the finding of a new study that has shown how neurons respond differently to real words compared to so-called ‘nonsense’ words.
During tests, brain scans revealed the new words appear as shapes rather than a group of letters in what researchers behind the study have dubbed a ‘visual dictionary.’
The study, carried out at Georgetown University Medical Centre, suggests brain is ‘holistically tuned’ to recognise complete words, according to the researchers.
Lead author Dr Maximilian Riesenhuber from the Laboratory for Computational Cognitive Neuroscience said: ‘We are not recognising words by quickly spelling them out or identifying parts of words, as some researchers have suggested.
‘Instead, neurons in a small brain area remember how the whole word looks – using what could be called a visual dictionary.’
The small area in the brain called the visual word form area is found in the left side of the visual cortex, opposite the fusiform face area on the right side, which remembers how faces look.
Dr Riesenhuber added: ‘One area is selective for a whole face, allowing us to quickly recognise people, and the other is selective for a whole word, which helps us read quickly.’
The study, published in the Journal of Neuroscience, looked at the brain activity of 25 adults who had learn a set of 150 nonsense words.
For the research the part of the brain associated with learning was examined using functional magnetic resonance imaging (fMRI).
Images of the brain were taken before and after participants learnt the new words.
From this, the team found the visual word form area changed as the participants learned the ‘nonsense’ words.
Before learning the words, neurons responded as though the training words were nonsense words.
But over time, the neurons began to respond as though they were learning real words.
Co-author Dr Laurie Glezer said: ‘This study is the first of its kind to show how neurons change their tuning with learning words, demonstrating the brain’s plasticity.’
The researchers said the study shows how the brain processes words, but may also provide insights into how to help people with reading disabilities.
Dr Riesenhuber said: ‘For people who cannot learn words by phonetically spelling them out – which is the usual method for teaching reading – learning the whole word as a visual object may be a good strategy.’
