Biology subjects

Sisk, L.

Publications and source records attributed to Sisk, L..

3 recordsLinked to original sources

bioRxiv2026

Highly replicable multisite patterns of adolescent white matter maturation

The Adolescent Brain Cognitive Development (ABCD) Study is the largest U.S.-based neuroimaging initiative of adolescent brain maturation. Diffusion MRI (dMRI) provides unique insights into white matter organization, yet applying advanced processing pipelines and managing technical variability across scanning environments remains challenging at scale. To address these issues, we present ABCD-BIDS Community Collection (ABCC) release 3.1.0, including a curated resource of more than 24,000 fully processed ABCD dMRI datasets. ABCC provides fully processed images, nuanced image quality metrics, advanced microstructural measures, and person-specific bundle tractography. Evaluating these rich data revealed that measures of diffusion restriction and non-Gaussianity--in particular the intracellular volume fraction from NODDI and return-to-origin probability from MAP-MRI--were highly sensitive to neurodevelopment and robust to variation in image quality. Additionally, harmonization of microstructural features markedly improved the cross-vendor generalizability of developmental effects. Together, ABCC accelerates reproducible, rigorous research on adolescent white matter development.

neuroscience↗

bioRxiv2020

Decomposing complex links between the childhood environment and brain structure in school-aged youth

Childhood experiences play a profound role in conferring risk and resilience for brain and behavioral development. However, how different facets of the environment shape neurodevelopment remains largely unknown. Here we sought to decompose heterogeneous relationships between environmental factors and brain structure in 989 school-aged children from the Adolescent Brain Cognitive Development Study. We applied a cross-modal integration and clustering approach called Similarity Network Fusion, which combined two brain morphometrics (i.e., cortical thickness and myelin-surrogate markers), and key environmental factors (i.e., trauma exposure, neighborhood safety, school environment, and family environment) to identify homogeneous subtypes. Depending on the subtyping resolution, results identified two or five subgroups, each characterized by distinct brain structure-environment profiles. Notably, more supportive caregiving and school environments were associated with increased myelination, whereas less supportive caregiving, higher family conflict and psychopathology, and higher perceived neighborhood safety were observed with increased cortical thickness. These subtypes were highly reproducible and predicted externalizing symptoms and overall mental health problems. Our findings support the theory that distinct environmental exposures differentially influence neurodevelopment. Delineating more precise associations between risk factors, protective factors, and brain development may inform approaches to enhance risk identification and optimize interventions targeting specific experiences.

neuroscience↗

bioRxiv2019

Sex differences in the effects of gonadal hormones on white matter microstructure development in adolescence

Adolescence, the transition between childhood and adulthood, is characterized by rapid brain development in white matter (WM) that is attributed in part to surges in gonadal hormones. To date, however, there have been no longitudinal investigations of the effects of gonadal hormones on WM development in adolescents. We acquired T1-weighted and diffusion-weighted MRIs at two timepoints and saliva samples from 80 adolescents (52 females [11.10{+/-}1.05 years at Time 1; 12.75{+/-}1.37 years at Time 2] and 28 males [ages 11.91{+/-}0.88 years at Time 1; 13.79{+/-}0.95 years at Time 2] who were matched on pubertal stage at Time 1. We estimated mean fractional anisotropy (FA) from 10 major WM tracts and assayed levels of testosterone (in both sexes) and estradiol (in females only). We used linear regression models to test whether interactions between sex and changes in testosterone levels significantly explained changes in FA. Sex significantly moderated the associations between changes in testosterone and changes in FA within the corpus callosum, inferior fronto-occipital fasciculus (IFOF), uncinate fasciculus (UF), and cingulum cingulate (all ps<0.05): whereas these associations were positive in females, they were not significant in males. Females also exhibited positive associations between changes in estradiol and changes in UF, IFOF, and corticospinal FA (all ps<0.05). Our findings indicate that sex differences in WM microstructure of tracts supporting cognitive control, response inhibition, and emotion regulation are explained by differences in changes in testosterone, and have important implications for understanding sex differences in brain development and psychosocial behaviors during the pubertal transition.

neuroscience↗