The human connectome

is the network of links between different parts of the brain. These links are mapped out by the brain’s white matter—bundles of nerve cell projections called axons that connect the nerve cell bodies that make up gray matter.

This structure is poorly understood, but there are several high-profile projects to study it. This work shows that the connectome is much more complex than originally thought. The human brain contains some 10¹⁰ neurons linked by 10¹⁴ synaptic connections. Mapping the way this link together is a tricky business, not least because the structure of the network depends on the resolution at which it is examined.  

https://www.geekbooks.me/book/view/data-science-for-dummies  

http://www.nactem.ac.uk/ace-mk/