February 29, 2024

How Left Brain Asymmetry Is Related to Reading Ability – Two “Opposing” Theories Are Both Correct

The scientists developed a way to determine levels of brain asymmetry from the MRI images utilizing consistent homology. They discovered that when the location of each individuals most asymmetric area was considered, greater left-brain asymmetry was related to much better pseudo-word reading ability. This supports a cerebral lateralization hypothesis. At the same time, they discovered that higher left-asymmetry in particular regions– consisting of a motor preparation area called Brodmann Area 8, and an efficiency monitoring area called the dorsal cingulate– were connected with typical reading capability, which supports a canalization hypothesis.
Of note was that pseudo-word reading ability was not consistently associated to asymmetries in brain areas understood to be crucial for specific language functions. How left/right structural asymmetries impact other types of reading abilities and influence the functions of a left language network stays to be studied.
Eckert includes, “Our findings indicate that, at a population level, structural brain asymmetries belong to the typical development of a speech sound processing capability that is necessary for developing proficient reading.”.
Recommendation: “Cortical asymmetries at different spatial hierarchies relate to phonological processing capability” by Mark A. Eckert, Kenneth I. Vaden Jr., Federico Iuricich and Dyslexia Data Consortium, 5 April 2022, PLOS Biology.DOI: 10.1371/ journal.pbio.3001591.
Funding: This work was supported (in part) by the National Institutes of Health (NIH)/ Eunice Kennedy Shriver National Institute of Child Health and Human Development (R01 HD 069374) (Author MAE) and was performed in a center constructed with support from Research Facilities Improvement Program (C06 RR 014516) from the NIH/National Center for Research Resources. Clemson University is acknowledged for its generous allocation of calculate time on the Palmetto cluster. The funders had no function in research study style, data collection and analysis, choice to publish, or preparation of the manuscript.

While structural asymmetries between the right and left sides of the brain appear to be related to this capability, exactly how stays a secret. Utilizing structural MRI from over 700 adults and children, along with a reading test of pseudo-words and a mathematical technique called persistent homology, the brand-new study checked 2 opposing theories of how brain asymmetries must impact phonological processing.

The researchers established a way to determine levels of brain asymmetry from the MRI images utilizing consistent homology.

Brain structure asymmetries are revealed, as defined with a novel topological technique that identifies appropriate functions (left) from noise within asymmetric structures (right). Credit: Federico Iuricich (CC-BY 4.0).
Various methods of looking at structural asymmetry program parallel results on processing of speech sounds related to dyslexia.
Researchers led by Mark Eckert at the Medical University of South Carolina, United States, report that 2 seemingly opposing theories of language processing are both proper. Released in the open-access journal PLOS Biology on April 5th 2022, the research study shows that greater left-brain asymmetry can anticipate both much better performance and typical efficiency on a foundational procedure of reading capability, depending upon whether analysis is performed over the whole brain or in particular regions.
Having the ability to fluently convert composed symbols into speech sounds is a basic element of reading that varies from person to person and is difficult for people with conditions like dyslexia. While structural asymmetries in between the right and left sides of the brain appear to be related to this ability, precisely how stays a mystery. Utilizing structural MRI from over 700 children and grownups, in addition to a reading test of pseudo-words and a mathematical approach called relentless homology, the brand-new study evaluated 2 opposing theories of how brain asymmetries need to affect phonological processing.