81 % of French people considered themselves as “readers” in 2021 according to an IPSOS study conducted for the National Book Center. However, some may find this exercise complex: dyslexic individuals may encounter difficulty in identifying words. To better understand the origins of this trouble, American researchers studied brain activity during reading. They published their findings in the Proceedings of the National Academy of Sciences (PNAS).
“Reading a sentence involves integrating the meanings of individual words to deduce a more complex and higher-order sense,” the authors explain at the outset of their study. “This very fast and complex human behavior is known to engage the inferior frontal gyrus (IFG) and middle temporal gyrus (MTG) in the linguistic-dominant hemisphere, but it is still unclear whether there are distinct contributions of these regions to sentence reading.” To understand this, they analyzed recordings of brain activity obtained while people were reading using electrodes. “The electrodes implanted in the brain provide us with a glimpse of the internal workings of the human mind, especially for rapid processes such as reading,” explains Nitin Tandon, co-author of the study. Neural activity of these patients was measured while reading three types of sentences: classical sentences, “Jabberwocky” sentences from Lewis Carroll’s poem, which have correct grammar and syntax but contain absurd words that deprive them of any meaning, and meaningless word lists.
This analysis allowed them to identify two brain networks that play a key role in the reading process. “One network involves a region of the frontal lobe of the brain that sends signals to the temporal lobe, which gradually activates as a person deduces complex meaning throughout a sentence,” they note. The second network is linked to a region of the temporal lobe of the brain that sends signals to a frontal lobe area: this allows for the integration of the context of a sentence to facilitate the understanding and processing of each new word read.
“This study helps us better understand how the hubs of the brain’s language network work together and interact to enable us to understand complex sentences,” says Oscar Woolnough, lead author of the study. “For us to understand language, there must be a precise sequence of rapid and dynamic processes occurring in multiple brain sites.” The researchers hope that this better understanding of the brain processes related to reading will lead to new research on the management of dyslexia.
#passetil #dans #cerveau #pendant #lecture
publish_date]
