Understanding ＂Chinese Brain＂ and Solving Dyslexia
◎ Our reporter Cui Shuang
Tens of millions of school-age children in China have serious reading difficulties, which seriously affect children’s learning and life quality. However, the existing findings can’t help us find the causal relationship between Chinese reading difficulties and cognitive factors.
Li-Hai Tan
Dean of Shenzhen Institute of Neuroscience
"The human brain has about 100 billion neurons, and the neurons are flashing, just like the stars are shining. But we know much less about the human brain than the starry sky. " On May 20th, Luo Yuejia, a professor at Beijing Normal University, said at the "Children’s Cognitive Development and Mental Health Summit Forum" held in Fuzhou, Fujian Province.
People’s different abilities correspond to different constellations in the brain universe. Chinese reading ability is like a constellation hidden behind the fog. Unlike reading pinyin, reading chinese involves a wider brain area and is more difficult to attribute.
A frontier project, which started in 2022, is trying to uncover the mystery of this constellation. This is the first large-scale and systematic follow-up study on the early warning system of Chinese dyslexia in China, starting with 3-year-old children. Scholars from many universities such as Beijing Normal University participated in it, and Shenzhen Institute of Neuroscience was responsible for providing specific research design and testing scheme.
Dyslexia is hereditary.
"Learning language and writing requires mobilizing various brain regions such as listening, speaking, watching and thinking. It is an extremely complex ability and can also reflect the development level of children’s cognitive ability." Xue Gui, a professor at Beijing Normal University, said.
Foreign studies have pointed out that language and reading ability are important contents of children’s cognitive development, which will have a far-reaching impact on children’s intellectual development and learning ability. About 20% children are seriously troubled by language and reading development difficulties. Early research by foreign scholars found that reading difficulties mainly stem from children’s defects in speech perception. Based on this discovery, foreign scholars have developed a systematic early diagnosis and intervention system for dyslexia.
Foreign studies have shown that more than 80% of pinyin reading disabilities stem from the defects of speech perception, which stems from the delayed development of related brain regions and is hereditary.
"Let a one-and-a-half-year-old or two-year-old child listen to a string of sounds such as ba, ba, ba, pa, ba, ba, pa, and monitor them with an electroencephalograph. When children hear pa, their brains will react and produce a negative wave. But some children hear pa, and there is no negative wave. Such children are more likely to show serious dyslexia when they enter primary school. If this situation is found in early diagnosis, parents can conduct targeted training and intervention when the child is one and a half years old or two years old. " Li-hai tan, president of Shenzhen Institute of Neuroscience, said.
However, this conclusion does not apply to Chinese dyslexia.
Chinese reading involves more brain regions.
"Tens of millions of school-age children in China have serious reading difficulties, which seriously affect children’s learning and quality of life, but the existing findings can’t help us find the causal relationship between Chinese reading difficulties and cognitive factors." Li-hai tan said.
Li-hai tan was one of the earliest scholars who studied languages (especially Chinese) by using functional magnetic resonance imaging technology. He discovered for the first time that Chinese should have a unique brain region for Chinese reading, which has become the consensus of neuroscience. Brain science research found that reading chinese needs a link to the "motor language center" in the prefrontal cortex — — The neural pathway between Bullokar area and auxiliary motor area, while reading pinyin requires a connection between Bullokar area and "auditory language center" — — Neural pathways in Wilnick’s area. In other words, "writing" is more important for the development of Chinese reading ability, while "listening" is more important for the development of English reading ability. The left middle frontal gyrus near the motor area of the brain is particularly important for Chinese processing. The formation of this reading center is highly related to children’s writing and reading chinese abilities.
The brain regions shared by Chinese and English reading include the inferior frontal gyrus, middle temporal gyrus and fusiform gyrus of the left brain. Chinese reading also involves the middle frontal gyrus of the left brain, the parietal lobe and the fusiform gyrus of the right brain, which are not the key brain regions for reading English. To learn the rules of letters corresponding to sounds in English reading, you need to use the temporal parietal region of the left brain, and reading chinese doesn’t need it either.
Because Chinese reading involves more brain regions, the incidence of language disorders in patients with cerebral palsy in mainland China was as high as 70%, while only 20% of patients with cerebral palsy in the United States had language disorders. Li-hai tan’s research results on Chinese involving brain regions have been applied in clinical practice to guide neurosurgery craniotomy, so that the operation can avoid the corresponding regions as much as possible. Previous studies suggest that the "problem brain regions" of Chinese-speaking dyslexics are mainly in the middle frontal gyrus, inferior frontal gyrus and parietal lobe of the left brain, while those of English-speaking dyslexics are mainly in the temporal parietal region of the left brain. Interestingly, the study in li-hai tan found that if children learning Chinese use pinyin input less, the gray matter in the left middle frontal gyrus is larger. In other words, if you overuse the pinyin input method, it will affect your child’s "Chinese brain".
Establish a database of children’s language development in China.
According to statistics, serious reading difficulties in Chinese are very common, which can reach 28% among school-age children. It is an urgent and important frontier scientific research task to break through the key technology of early intervention of Chinese dyslexia from 0 to 1, which is related to the improvement of education quality in China.
Li-hai tan said that a two-and-a-half-year-old child has an average of 2.5 words per sentence; 4 years old rose to 6 words; At the age of five, it was seven words, which was close to 8.3 words for adults. Therefore, the rapid development of children’s language is in 2-mdash; Four years old.
Language development is highly correlated with brain weight gain — — At birth, the baby’s brain weighs 0.454 kg; The brain weight of a 1-year-old child is almost 1 kg; 4— The brain weight of 5-year-old children is equivalent to 80% of that of adults & mdash; 90%。 Before the age of 5, the child’s brain developed very rapidly.
Second language learning is also the sooner the better. Many years ago, an American study showed that 3-mdash; Children who immigrated to the United States at the age of 7 have the same probability of making mistakes when using English as children whose mother tongue is English; 8— At the age of 10, the correct rate of children who immigrated to the United States to use English declined; 11— The correct rate of using English by teenagers who immigrated to the United States at the age of 15 decreased obviously; And the efficiency of adults learning a second language is greatly reduced.
Because the early warning system of reading difficulties in the west is not suitable for children in China, it is only through long-term follow-up study that it is possible to find out the development law of children’s language and reading ability, but there has never been a large-scale long-term follow-up study for kindergarten children in China. Based on this realistic demand, Shenzhen Institute of Neuroscience has cooperated closely with Rongqiao Kindergarten in Fuzhou. In the five years from 2022, the laboratory of Shenzhen Institute of Neuroscience in Fuzhou will conduct follow-up research on nearly 1,000 3-year-old children.
"We hope to build a 3-mdash; A five-year tracking database of language development of 4-year-old children in China. " Li-hai tan said that they will pass a survey of 3,000 3— 4-year-old children carry out the cognitive test task of original design to reveal the law of language development.
Li-hai tan said that each child will take 15 quizzes similar to games, covering various brain functions, such as listening, speaking, watching, reacting and understanding, which will last for two to three hours and be completed several times. The research will also include gene sequencing.
In the future, after these children go to primary school, researchers will observe their reading performance again, which may gain a regular understanding and provide theoretical guidance for improving their reading ability.
According to the characteristics of region and language, the researcher finally chose Fuzhou as the key experimental city, and selected seven kindergartens under Rongqiao Kindergarten for testing. Li Xiaolei, director of Fuzhou Rongqiao Kindergarten, said that in November last year, the scientific research project was launched in Rongqiao Kindergarten. With the support of teachers and parents, nearly 1,000 children participated in the research and successfully completed the task of the first year. She hopes that the study can find early warning indicators of dyslexia, and lay a solid foundation for improving children’s language cognitive ability in China.
At present, the research is still carried out in some kindergartens in Chengdu, Sichuan Province. About 3,000 children across the country participated.