title: How does your cortex grow?
abstract: Understanding human cortical maturation is a central goal for developmental neuroscience. Significant advances toward this goal have come from two recent strands of in vivo structural magnetic resonance imaging research: (1) longitudinal study designs have revealed that factors such as sex, cognitive ability, and disease are often better related to variations in the tempo of anatomical change than to variations in anatomy at any one time point; (2) largely cross-sectional applications of new surface-based morphometry (SBM) methods have shown how the traditional focus on cortical volume (CV) can obscure information about the two evolutionarily and genetically distinct determinants of CV: cortical thickness (CT) and surface area (SA). Here, by combining these two strategies for the first time and applying SBM in >1250 longitudinally acquired brain scans from 647 healthy individuals aged 3-30 years, we deconstruct cortical development to reveal that distinct trajectories of anatomical change are hidden within, and give rise to, a curvilinear pattern of CV maturation. Developmental changes in CV emerge through the sexually dimorphic and age-dependent interaction of changes in CT and SA. Moreover, SA change itself actually reflects complex interactions between brain size-related changes in exposed cortical convex hull area, and changes in the degree of cortical gyrification, which again vary by age and sex. Knowing of these developmental dissociations, and further specifying their timing and sex-biases, provides potent new research targets for basic and clinical neuroscience.
authors.affiliation: Child Psychiatry Branch, National Institute of Mental Health, Bethesda, Maryland 20892, USA. raznahana@mail.nih.gov
authors.forename: Armin
authors.initials: A
authors.lastname: Raznahan
authors.forename: Phillip
authors.initials: P
authors.lastname: Shaw
authors.forename: Francois
authors.initials: F
authors.lastname: Lalonde
authors.forename: Mike
authors.initials: M
authors.lastname: Stockman
authors.forename: Gregory L
authors.initials: GL
authors.lastname: Wallace
authors.forename: Dede
authors.initials: D
authors.lastname: Greenstein
authors.forename: Liv
authors.initials: L
authors.lastname: Clasen
authors.forename: Nitin
authors.initials: N
authors.lastname: Gogtay
authors.forename: Jay N
authors.initials: JN
authors.lastname: Giedd
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000254:growth & development*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D009929:Organ Size; D012737:Sex Factors