Profiling intra- and inter-individual differences in brain development across early adolescence

Abstract

As we move toward population-level developmental neuroscience, understanding intra- and interindividual variability in brain maturation and sources of neurodevelopmental heterogeneity becomes paramount. Large-scale, longitudinal neuroimaging studies have uncovered group-level neurodevelopmental trajectories, and while recent work has begun to untangle intra- and interindividual differences, they remain largely unclear. Here, we aim to quantify both intra- and inter-individual variability across facets of neurodevelopment from late childhood to early adolescence in the Adolescent Brain Cognitive Development (ABCD) Study, and examine the contributions of age, sex, puberty, sociodemographic factors, and MRI scanner manufacturer to inter-individual variability. Our results provide novel insight into differences in microstructure development between cortical and subcortical gray matter. We found that an individual's starting point is related to how their brain changes, across all brain outcomes. Although both sex and pubertal status contributed to inter-individual variability, we found limited support for hypotheses regarding greater male-than-female variability and increases in inter-individual variability throughout puberty. Finally, we uncovered enmeshed contributions of sociodemographics and MRI scanner manufacturers to inter-individual variability in this dataset, due in part to sociodemographic differences in participants scanned on Siemens, GE, and Philips MRIs. This work highlights pockets of individual variability for future investigation, describes a promising approach for quantifying deviations from normative development, and urges caution in covariate choice for investigators using ABCD Study data.

Traces of pubertal brain development and health revealed through domain adapted brain network fusion

“…However, the significant association of the Δembedding with the pubertal Δ, also when controlling for overall puberty status at baseline and Δage, suggests that our framework can capture longitudinal dynamics of development. While studies on normative brain development generally report overarching brain trajectories across different brain measures 25 , recent work by Bottenhorn and colleagues 26 highlight a high degree of intra- and interindividual variability in brain maturation across imaging measures. Identifying and understanding these sources of variance depict an important step towards population-level neuroscience, which however may complicate downstream analyses because of the heterogeneity across regions and imaging measures.…”

“…Potential limitations might stem from the fact that only two imaging modalities, that is brain volume and surface area, were integrated in our framework. The reasoning behind this decision was twofold: First, since brain volume and area follow a comparable normative developmental trajectory from late childhood into late adolescence 25 , building similarity networks on both measures may result in robust and non-sparse reference space that allows to better disentangle sex effects, since additional heteroscedasticity of different imaging measures may be mitigated 26 .…”