Typical brain development in relation to reading

The process of learning to read is one of the crucial milestones in a child's cognitive development, and is intrinsically linked to typical brain development.

In this session, we will explore how the brain evolves in relation to reading throughout the stages of development, from childhood to adolescence. We will analyze key brain areas, neuronal plasticity, and the importance of genetic and environmental factors in this fundamental process.

Neurobiological Foundations in Childhood

• Fusiform Gyrus Development: In the early stages of development, the fusiform gyrus, a region crucial for visual word processing, undergoes rapid development. Babies show an innate preference for faces, and this region is also involved in the recognition of visual patterns, laying the foundations for the recognition of letters and words in reading.

• Neuronal Plasticity in the Early Years: Neuronal plasticity, the brain's ability to change and adapt in response to experience, is remarkable in childhood. Exposure to visual stimuli, such as illustrated books and large print, contributes to the development of visual skills that are essential for later reading.

The Phonological Route and the Development of Auditory Skills

• Development of Angular Gyrus: As children progress through preschool, the angular gyrus, involved in phonological processing, begins to play a more significant role. The connection between letters and sounds, fundamental for reading, develops gradually as children participate in activities related to sound and language.

• Development of Auditory Skills: Auditory skills, including sound discrimination and phonological awareness, experience considerable progress during the first school years. Games involving rhymes, word play and listening to stories contribute to the development of these auditory skills, which are fundamental for the take-off in reading.

Consolidation of the Lexical Route in Early Childhood

• Development of the Frontal Lobe: During early childhood, the frontal lobe, associated with lexical processing and access to the mental lexicon, begins to mature. Children begin to recognize and store words in their memory, forming connections between written forms and their meanings.

• Linking the inferior frontal gyrus with working memory: As the inferior frontal gyrus strengthens, connections are established with regions associated with working memory. This interaction allows children to retain information about words as they progress through reading, facilitating the comprehension of more complex sentences and texts.

Development of Neural Connections at School Age

• Corpus Callosum and Hemispheric Coordination: At school age, the corpus callosum, which facilitates communication between the cerebral hemispheres, undergoes greater myelination and maturation. Hemispheric coordination is essential for integrating visual and phonological information during reading, and this maturation contributes to greater efficiency in this process.

• Development of Specialized Circuits: More specialized brain circuits for reading are developed as children practice and refine their skills. The repetition and practice of reading contribute to the formation of specific neural circuits, improving the speed and accuracy in the processing of written information.

Adolescence and Consolidation of Reading Skills

• Refinement of Brain Connections: During adolescence, brain connections continue to refine and consolidate. Continuous reading experience, now more complex, reinforces and optimizes the neural circuits associated with word recognition, lexical comprehension and coordination between specialized brain regions.

• Development of the Parietal Cortex: The parietal cortex, involved in working memory functions, undergoes significant development. This improves the ability of adolescents to retain information in the short term while reading longer and more complex texts.

Genetic and Environmental Factors in Reading Development

• Genetic Predisposition: Genetic predisposition plays a role in reading development. Studies with twins have highlighted the influence of genetic factors on reading skills. The heritability of certain components, such as processing speed and working memory, affects the ease with which a child can learn to read.

• Importance of Experience and Education: Although genetics are an important factor, experience and the quality of education are also crucial. An environment rich in visual and auditory stimuli, together with an effective pedagogical approach, can have a significant impact on the development of reading skills.

Challenges and Variability in Reading Development

• Diversity in the Pace of Development: It is important to note that there is considerable variability in the pace of reading development among children. Some children may face temporary challenges, but with time and adequate support, many overcome these challenges and develop strong reading skills.

• Developmental Difficulties: Some children may face persistent difficulties in reading development, which could be indicators of possible learning disorders such as dyslexia. Early identification and appropriate interventions are essential to address these difficulties.