Abstract
Changes in cortical thickness occur throughout the lifespan, but the neurobiological substrates are poorly understood. Here, we compared the regional patterns of cortical thinning (Magnetic Resonance Images; >4000 observations) with those of gene expression for several neuronal and non-neuronal cell types (Allen Human Brain Atlas). Inter-regional profiles of cortical thinning (estimated from MRIs) related to expression profiles for marker genes of CA1 pyramidal cells, astrocytes and microglia during development (less thinning, greater gene expression). The same expression – thinning patterns were mirrored in aging, but in the opposite direction. The results were replicated in independent MRI datasets. Further analyses suggested that the cell type – thinning relationship is facilitated by astrocytic metabolic processes in development and neural projection and synaptic changes in aging. Overall, these findings uncover the neurobiological mechanisms underlying cortical thinning across the lifespan and may contribute to our understanding of the molecular pathways involved in neurodevelopmental and neurodegenerative disorders.
Footnotes
↵& Data used in the preparation of this article were partially obtained from the Australian Imaging Biomarkers and Lifestyle flagship study of ageing (AIBL) funded by the Commonwealth Scientific and Industrial Research Organisation (CSIRO), which was made available at the ADNI database (www.loni.usc.edu/ADNI). The AIBL researchers contributed data but did not participate in analysis or writing of this report. AIBL researchers are listed at www.aibl.csiro.au.