The Primary-association Gradient across the Human Lifespan

Motivation: While prior studies have documented age-related changes in the primary-association gradient using functional MRI data, several gaps remain. Goal(s): A continuous understanding of the functional primary-association gradient, based on large sample sizes, advanced processing methods, standard statistical frameworks, and comprehensive validation analyses, is critically needed. Approach: Functional connectomes were constructed by calculating the pairwise correlation coefficient between the time series of all vertices . Using diffusion map embedding, we derived functional gradients from age-specific group-level functional connectome and individual functional connectome respectively. Results: We delineate the growth of functional connectome gradients, and its underlying structural mechanisms and supports for cognitive spectrum across the lifespan. Impact: Results advance our understanding of the lifespan changes in topographic organization of the human brain and its impact on cognitive spectrum.