Connectomics is the comprehensive mapping and analysis of neural connections in the brain — the connectome. At the macro scale, diffusion tensor imaging (DTI) and functional connectivity analysis map the major white matter tracts and functional networks connecting brain regions. At the micro scale, electron microscopy reconstructs every synapse in small volumes of neural tissue. The goal is to understand how the brain's wiring diagram constrains and enables cognitive function.
Structural and Functional Connectomes
The structural connectome maps anatomical connections (white matter fiber tracts), while the functional connectome maps statistical dependencies in brain activity (regions whose activity rises and falls together). Graph-theoretic analysis reveals that the brain has "small-world" network properties: most processing occurs in densely connected local clusters, while a few long-range connections enable efficient global communication. Hub regions (like the posterior cingulate and lateral prefrontal cortex) serve as integration points connecting multiple networks.
Connectome "fingerprints" — individual patterns of functional connectivity — can identify individuals with high accuracy and predict cognitive abilities including fluid intelligence, attention, and personality traits. The Human Connectome Project has collected high-resolution brain connectivity data from over 1,000 individuals, providing an unprecedented resource for understanding how network architecture varies across individuals and relates to cognitive and behavioral differences.