Connectome

A connectome is a comprehensive map of all neural connections in a nervous system, from a single organism to an entire brain. Like a detailed cartographic rendering of synapses and neurons, it attempts to capture the wiring diagram that underlies thought, behavior, and sensation.

The term comes from "connection" and the "-ome" suffix (as in genome). Connectomes vary wildly in scale: scientists have fully mapped the 302-neuron connectome of C. elegans (a tiny worm), while mammalian brains contain billions of neurons and trillions of connections—far beyond current complete mapping.

Creating a connectome requires extraordinary effort: tissue slicing, electron microscopy, image analysis, and often probabilistic reconstruction to bridge gaps. The C. elegans connectome, completed in 1986, remains one of neuroscience's crown jewels, yet even it hasn't fully explained behavior—revealing that connection maps alone don't determine function.

Modern efforts like Google's and Facebook's AI labs are attacking larger connectomes using machine learning and automated measurement. These maps promise insights into how evolution shaped intelligence, how learning physically rewires the brain, and potentially how to model or repair damaged neural tissue.

Related

Neuron, Synapse, Brain mapping, Microscopy, Machine learning, Consciousness