Growth of white matter in the adolescent brain: myelin or axon?
White matter occupies almost half of the human brain. It contains axons connecting spatially segregated modules and, as such, it is essential for the smooth flow of information in functional networks. Structural maturation of white matter continues during adolescence, as reflected in age-related changes in its volume, as well as in its microstructure. Here I review recent observations obtained with magnetic resonance imaging in typically developing adolescents and point out some of the known variations in structural properties of white matter vis-à-vis brain function in health and disease. I conclude by re-focusing the interpretations of MR-based studies of white matter from myelin to axon.
Paus
Tomás
T
Brain and Body Centre, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom. tomas.paus@nottingham.ac.uk
D000293:Adolescent; D000818:Animals; D001369:Axons / Q000502:physiology* / Q000648:ultrastructure; D001921:Brain / Q000254:growth & development* / Q000502:physiology* / Q000648:ultrastructure; D006801:Humans; D009186:Myelin Sheath / Q000502:physiology* / Q000648:ultrastructure; D009413:Nerve Fibers, Myelinated / Q000502:physiology* / Q000648:ultrastructure; D009434:Neural Pathways / Q000254:growth & development / Q000502:physiology / Q000648:ultrastructure