RT Journal Article
SR Electronic
T1 Graded Variation In Cortical T1w/T2w Myelination During Adolescence
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2021.12.06.471432
DO 10.1101/2021.12.06.471432
A1 Graham L. Baum
A1 John C. Flournoy
A1 Matthew F. Glasser
A1 Michael P. Harms
A1 Patrick Mair
A1 Ashley Sanders
A1 Deanna M. Barch
A1 Randy L. Buckner
A1 Susan Bookheimer
A1 Mirella Dapretto
A1 Stephen Smith
A1 Kathleen M. Thomas
A1 Essa Yacoub
A1 David C. Van Essen
A1 Leah H. Somerville
YR 2021
UL http://biorxiv.org/content/early/2021/12/07/2021.12.06.471432.abstract
AB Myelination influences brain connectivity during sensitive periods of development by enhancing neural signaling speed and regulating synapse formation to reduce plasticity. However, in vivo studies characterizing the maturational timing of cortical myelination during human development remain scant. Here, we take advantage of recent advances in high-resolution cortical T1w/T2w myelin mapping methods, including principled correction of B1+ transmit field effects, using data from the Human Connectome Project in Development (N=628, ages 8-21) to characterize the maturational timing of myelination from childhood through early adulthood throughout the cerebral neocortex. We apply Bayesian spline models and functional latent clustering analysis to demonstrate graded variation in the rate of cortical T1w/T2w myelin growth in neocortical areas that is strongly correlated with the sensorimotor-association (S-A) axis of cortical organization reported by others. In sensorimotor areas T1w/T2w myelin starts at high levels at early ages, increases at a fast pace, and decelerates at later ages (18-21). In intermediate multimodal areas along the S-A axis, T1w/T2w myelin tends to start at intermediate levels and increase linearly at an intermediate pace. In transmodal/paralimbic association areas high along the S-A axis, T1w/T2w myelin tends to start at low levels and increase linearly at the slowest pace. These data provide evidence for graded variation along the S-A axis in the rate of cortical myelination during adolescence, which could reflect ongoing plasticity underlying the development of complex information processing and psychological functioning.Significance Statement Myelin is a lipid membrane that is essential to healthy brain function. Myelin wraps axons to increase neural signaling speed, enabling complex neuronal functioning underlying learning and cognition. Here we characterize the developmental timing of myelination across the cerebral cortex during adolescence using recent advances in non-invasive myelin mapping. Our results provide new evidence demonstrating graded variation across the cortex in the timing of myelination during adolescence, with rapid myelination in lower-order sensory areas and gradual myelination in higher-order association areas. This spatial pattern of microstructural brain development closely parallels the sensorimotor-to-association axis of cortical organization and plasticity during ontogeny.Competing Interest StatementThe authors have declared no competing interest.