[Article Review] The Gut-Brain Connection: Bacteroidetes-Dominant Microbiome Linked to Enhanced Neurodevelopment in Infancy

Reference

Tamana, S. K., Tun, H. M., Konya, T., Chari, R. S., Field, C. J., Guttman, D. S., Becker, A. B., Moraes, T. J., Turvey, S. E., Subbarao, P., Sears, M. R., Pei, J., Scott, J. A., Mandhane, P. J., & Kozyrskyj, A. L. (2021). Bacteroides-dominant gut microbiome of late infancy is associated with enhanced neurodevelopment. Gut Microbes, 13(1), 1930875. https://doi.org/10.1080/19490976.2021.1930875

Review

The article by Tamana et al. (2021) investigates the association between gut microbiota and early neurodevelopment in infants. The authors analyzed data from 405 infants from the Canadian Healthy Infant Longitudinal Development (CHILD) Cohort Study, using the Bayley Scale of Infant Development (BSID-III) to assess neurodevelopmental outcomes at 1 and 2 years of age. Fecal samples were collected at a mean age of 4 and 12 months for microbiota profiling using 16S rRNA gene sequencing.

The study identified three infant groups based on the relative abundance of gut microbiota at 12 months: Proteobacteria-dominant, Firmicutes-dominant, and Bacteroidetes-dominant clusters. The Bacteroidetes-dominant cluster demonstrated a significant positive association with cognitive, language, and motor development scores at age 2, particularly among male infants. The genus Bacteroides abundance in gut microbiota was positively correlated with cognitive and language scores at age 2. The study found no associations between 4-month microbiota clusters and BSID-II scores.

Tamana et al. (2021) suggest that Bacteroidetes-dominant gut microbiota in late infancy is associated with better neurodevelopment, particularly in males. Enhanced sphingolipid synthesis and metabolism, as well as antagonism or competition between Bacteroides and Streptococcus, were characteristic of Bacteroidetes-dominant gut microbiota. This study contributes valuable insights into the gut-brain connection and the potential impact of gut microbiota on early neurodevelopment.

Dissecting Cognitive Measures in Reasoning and Language at Cogn-IQ.org

The study scrutinizes the dimensions of general reasoning ability (gθ) as gauged by the Jouve-Cerebrals Test of Induction (JCTI) and the Scholastic Assessment Test-Recentered (SAT), specifically its Mathematical and Verbal subscales. Conducting a principal components factor analysis with a sample of American students, the study elucidates a bifurcated cognitive landscape. The Mathematical SAT and JCTI robustly align with inductive reasoning abilities, ostensibly representing a general reasoning factor. 

Conversely, the Verbal SAT demonstrates a considerable orientation toward language development. This nuanced delineation of cognitive faculties suggests that while the Mathematical SAT and JCTI robustly map onto general reasoning, the Verbal SAT serves as a distinct indicator of language development skills. 

Notwithstanding the limitations of sample size and the exclusion of top SAT performers, these insights advance the discourse on the psychometric properties of these assessments and their correlation with cognitive abilities. The exploration paves the way for more expansive studies that could further substantiate the interrelations among these cognitive domains and refine our comprehension of educational assessment tools.

Reference: Jouve, X. (2010). Uncovering The Underlying Factors Of The Jouve-Cerebrals Test Of Induction And The Scholastic Assessment Test-Recentered. Cogn-IQ Research Papers. https://www.cogn-iq.org/doi/04.2010/dd802ac1ff8d41abe103