Natural Connection Patterns Drive Brain Development
Post by Lincoln Tracy
What's the science?
Different areas of our brains are responsible for different functions. Some are responsible for our vision, others are responsible for our movement, while others are responsible for our ability to talk. However, the underlying mechanisms driving the functional specialization of these different brain regions are unknown. This week in Scientific Reports, Li and colleagues tested the hypothesis that intrinsic connectivity patterns between brain regions provide a scaffold for functional specialization to occur at a later point in time. To test this hypothesis, they explored whether the visual word form area (VWFA - the part of our brain responsible for identifying words and letters from shapes prior to their association with semantics) is connected to other language areas in infants less than a week old.
How did they do it?
The authors used data released by the Developing Human Connectome Project and the Human Connectome Project. Specifically, they analyzed high-resolution functional magnetic resonance imaging (fMRI) data for 40 newborns less than one week old and 40 adults aged 22-36 years old (15 females in each group). The authors were particularly interested in functional connectivity (FC) – the similarity between spontaneous brain signals arising from two different regions – of the VWFA to other brain regions. They examined whether the VFWA of week-old infants displayed established connections with other language regions of the brain.
What did they find?
The authors found that week-old infants have similar FC patterns when compared to adults, with the greatest connectivity between the VFWA and other language regions of the brain. Infants and adults displayed similar connectivity in the language network of the brain, but infants displayed a lack of connectivity between the VWFA and typical language network regions observed in adults. The authors also observed that the VFWA in both infants and adults displayed greater connectivity with language regions compared to non-language regions that were adjacent to key language network regions. Some differences were observed, where infants displayed less differentiation of the VWFA and adjacent visual object processing regions than adults These results suggest that the connectivity between the different brain regions involved in the language network is enhanced and refined as we gain literacy.
What's the impact?
This study provides support for the hypothesis that intrinsic connections between brain regions help guide further brain development as we age. Many research questions remain unanswered, such as how reading changes connections between regions within the developing brain, and how connection patterns arise prenatally. Further advances in developmental neuroimaging will make it possible to begin to answer these questions.
Li et al. Innate connectivity patterns drive the development of the visual word form area. Scientific Reports (2020).Access the original scientific publication here.