The idea that each brain is unique since it "codes" unique experiences is not new at all. What is new is that scientists now have been able to demonstrate it by showing that the local connectome is indeed unique for each brain, to the point that it can be used as a fingerprint of a person. More than that. This local connectome is ever changing, reflecting the new experiences, some 13% of it changes every 100 days (which does not mean that close to 50% of our brain changes every year…). Clearly, the fact that it keeps changing would make fingerprinting tricky… over time.
The research was carried out at Carnegie Mellon University and recently published on Computational Biology Journal.
The local connectome, as opposed to the "connectome" that is the ensemble of all connections among regions of the brain created by axons and dendrites, is the degree of connections (density of connections) among contiguous voxels in the white matter (tiny volumes, usually cubic in shape). It can be measured by the density of the diffused water in a specific area. The collection of several of these density measurement can be described by a vector that is representing that local connectome. The studies from the team at Carnegie Mellon based on 699 brains was performed using MRI. They run over 17,000 identification tests and proved the unicity of the vectors generated, basically showing a fingerprint for a brain.
The study also shown that identical twins are not that "identical" since at brain level they only share about 12% of the connectivity structure.