Specialization and Flexibility in Human Association Cortex

We applied a hierarchical Bayesian model (figure on right) on 10,449 Brainmap experiments across 83 behavioral tasks. By formalizing the notion that performing a task engages multiple cognitive components, each supported by overlapping brain regions, we identified cognitive components that are shared across tasks. The estimated components enabled the derivation of quantitative maps of functional specialization, revealing complex zones of frontal and parietal regions ranging from being highly specialized to highly flexible. An independent resting-state fMRI dataset (N=1000) was used to explore the network organization of the specialized and flexible regions. Cortical regions specialized for the same components were strongly coupled, suggesting that components function as partially isolated networks. Functionally flexible regions participate in multiple components to different degrees. This heterogeneous selectivity was strongly predicted by the connectivity between functionally flexible and specialized regions. Functionally flexible regions might support the core of the brain’s information processing capacity, binding or integrating the processing power of segregated, specialized brain networks. The estimated components in FreeSurfer fsaverage space and MNI152 space, as well as specificity and flexibility estimates are available for download.