Sex-biased trajectories of amygdalo-hippocampal morphology change over human development
Ari M. Fish,
Ajay Nadig,
Jakob Seidlitz,
Paul K. Reardon,
Catherine Mankiw,
Cassidy L. McDermott,
Jonathan D. Blumenthal,
Liv S. Clasen,
Francois Lalonde,
Jason P. Lerch,
M. Mallar Chakravarty,
Russell T. Shinohara,
Armin Raznahan
Affiliations
Ari M. Fish
Developmental Neurogenomics Unit, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD, 20892, USA
Ajay Nadig
Developmental Neurogenomics Unit, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD, 20892, USA
Jakob Seidlitz
Developmental Neurogenomics Unit, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD, 20892, USA
Paul K. Reardon
Developmental Neurogenomics Unit, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD, 20892, USA
Catherine Mankiw
Developmental Neurogenomics Unit, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD, 20892, USA
Cassidy L. McDermott
Developmental Neurogenomics Unit, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD, 20892, USA
Jonathan D. Blumenthal
Developmental Neurogenomics Unit, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD, 20892, USA
Liv S. Clasen
Developmental Neurogenomics Unit, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD, 20892, USA
Francois Lalonde
Developmental Neurogenomics Unit, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD, 20892, USA
Jason P. Lerch
Department of Medical Biophysics, University of Toronto, Toronto, ON, M5T 1R8, Canada; Neurosciences and Mental Health, the Hospital for Sick Children, Toronto, ON, M5T 3H7, Canada
M. Mallar Chakravarty
Cerebral Imaging Centre, Douglas Mental Health University Institute, McGill University, Montreal, QC, Canada, H3A OG4; Departments of Psychiatry and Biological and Biomedical Engineering, McGill University, Montreal, QC, H3A OG4, Canada
Russell T. Shinohara
Department of Biostatistics, Epidemiology, and Informatics, Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
Armin Raznahan
Developmental Neurogenomics Unit, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD, 20892, USA; Corresponding author.
The amygdala and hippocampus are two adjacent allocortical structures implicated in sex-biased and developmentally-emergent psychopathology. However, the spatiotemporal dynamics of amygdalo-hippocampal development remain poorly understood in healthy humans. The current study defined trajectories of volume and shape change for the amygdala and hippocampus by applying a multi-atlas segmentation pipeline (MAGeT-Brain) and semi-parametric mixed-effects spline modeling to 1,529 longitudinally-acquired structural MRI brain scans from a large, single-center cohort of 792 youth (403 males, 389 females) between the ages of 5 and 25 years old. We found that amygdala and hippocampus volumes both follow curvilinear and sexually dimorphic growth trajectories. These sex-biases were particularly striking in the amygdala: males showed a significantly later and slower adolescent deceleration in volume expansion (at age 20 years) than females (age 13 years). Shape analysis localized significant hot-spots of sex-biased anatomical development in sub-regional territories overlying rostral and caudal extremes of the CA1/2 in the hippocampus, and the centromedial nuclear group of the amygdala. In both sexes, principal components analysis revealed close integration of amygdala and hippocampus shape change along two main topographically-organized axes – low vs. high areal expansion, and early vs. late growth deceleration. These results (i) bring greater resolution to our spatiotemporal understanding of amygdalo-hippocampal development in healthy males and females, and (ii) uncover focal sex-differences in the structural maturation of the brain components that may contribute to differences in behavior and psychopathology that emerge during adolescence.
