While it is not yet known what can be attributed to the divergent results, given the fact there are many milestones in development whose appearance in time corresponds across humans, the major differences that have been proposed in the developmental trajectory of the brain seem unlikely to represent reality. However, LCBC believes that the current state of the research field does not allow one to draw conclusions as to which of the proposed models most accurately represents the normal development of the brain. Instead, the paper proposes 2 ways in which scientists in the field can begin to reach a consensus. Crucially, for accurate estimation of cortical thickness one must first accurately delineate the grey matter (red line, fig. 2) and white matter boundaries (yellow line, fig. 2) that border the cortex (here, surface-based techniques that measure thickness at every point on the cortex using a mesh representation (fig. 3) excel). First, implementing the combined use of different types of MR images, specifically T2-weighted images, could help improve the estimation of the cortical boundary by boosting the MRI-derived signal, and thus may improve thickness estimations. Secondly, encouraging greater sharing of datasets amongst research groups would help identify to what degree different data processing and analysis strategies can influence the results observed, by subjecting the same dataset to different processing pipelines.
LCBC believes that such strategies could facilitate greater knowledge, and potentially also pave the way for reaching a scientific consensus as to how the cerebral cortex matures throughout development. Given that it will also shed light on developmental paths that lead to aberrant development, the paper submits that it is now critical that we begin to form a unified understanding of the brain mechanisms underlying healthy brain development.