What is a connectome?

A connectome is a comprehensive map of all the connections in a brain. It includes every neuron, every synapse, and every other incidental component of the network required to characterize the higher order information in the brain. The connectome describes how to build your memories, personality, and mind, just as the genome (which is all of the DNA of an individual), describes how to build your body.

The connectome is commonly defined in two ways:

• A technical definition of the connectome is often limited to the gross anatomical connections (how neurons connect to each other) in the brain. This alone is not considered fully sufficient to contain our unique memories and experiences.
• An expanded definition of the connectome includes not only the anatomical connections between neurons, but also the types and concentrations of special information-encoding molecules at each synapse (the “synaptome”), in the nucleus (the “epigenome”) and elsewhere in the neuron that may also store our unique memories, experiences, and individuality.

When BPF advisor Sebastian Seung says “I am my connectome,” he is using the expanded definition of the connectome. We use the word connectome in this expanded definition as well. See this talk by Professor Sebastian Seung for more details.